THE EFFECT OF ACUTE FLUID CONSUMPTION FOLLOWING EXERCISE-INDUCED FLUID LOSS ON HYDRATION STATUS, PERCENT BODY FAT, AND MINIMUM WRESTLING WEIGHT IN WRESTLERS PAUL T. CUTRUFELLO1
AND
CURT B. DIXON2
1
Department of Exercise Science and Sport, The University of Scranton, Scranton, Pennsylvania; and 2Health Science Department, Lock Haven University, Lock Haven, Pennsylvania ABSTRACT
Cutrufello, PT and Dixon, CB. The effect of acute fluid consumption following exercise-induced fluid loss on hydration status, percent body fat, and minimum wrestling weight in wrestlers. J Strength Cond Res 28(7): 1928–1936, 2014— Acute fluid consumption (approximately 1 L) has been shown to reduce urine specific gravity (Usg) among subjects after an overnight fast, yet it is unknown if Usg may be reduced among subjects who have experienced exercise-induced fluid loss. The purpose of this study was to examine the effect of acute fluid consumption on Usg, body mass, percent body fat (%BF), and minimum wrestling weight (MWW) following an exerciseinduced fluid loss protocol. National Collegiate Athletic Association coaches’ perceptions of the weight certification program (WCP) were also evaluated. Twelve men wrestlers (19.8 6 1.14 years) were tested prepractice (PRE), postpractice (POST), and 1 hour after consuming 1 L of water (PFC). Percent body fat was measured by skinfolds (SF), air displacement plethysmography (ADP), and multifrequency and leg-to-leg bioelectrical impedance analysis to calculate MWW. Urine specific gravity measurements significantly increased above PRE (1.013 6 0.006) at the POST (1.019 6 0.007; p = 0.017) and PFC (1.022 6 0.008; p = 0.025) assessments; however, POST and PFC were not significantly different (p = 0.978) from one another. The %BF values were similar (p . 0.05) at each assessment point when using SF and ADP. When compared with PRE, MWW significantly reduced at the POST assessment when using SF (67.2 6 8.4 vs. 65.7 6 8.2 kg; p , 0.001) and ADP (66.6 6 9.1 vs. 64.8 6 9.0 kg; p = 0.001), reflecting the reduction in body mass observed after exercise. Forty-seven National Collegiate Athletic Association coaches completed the questionnaire and 2 central Address correspondence to Paul T. Cutrufello, paul.cutrufello@scranton. edu. 28(7)/1928–1936 Journal of Strength and Conditioning Research Ó 2014 National Strength and Conditioning Association
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themes emerged: (a) concerns with the 1.5% weight loss plan and (b) wrestlers using strategies in an attempt to circumvent the WCP. Exercise-induced fluid loss followed by acute fluid consumption equal to 1 L was ineffective in reducing Usg.
KEY
WORDS
specific gravity, impedance, plethysmography
skinfold,
bioelectrical
INTRODUCTION
I
n response to the unfortunate deaths of 3 collegiate wrestlers in 1997, related to rapid weight loss and intentional dehydration (18), the National Collegiate Athletic Association (NCAA) implemented a wrestling weight certification program (WCP) during the 1998– 1999 season (28). The WCP is designed to reduce the unhealthy weight loss practices that have been reported in the sport of wrestling (19,21,30). As part of the WCP, the NCAA requires that each wrestler have their percent body fat (%BF) determined preseason while properly hydrated to establish a minimum wrestling weight (MWW). The NCAA has defined urine specific gravity (Usg) , 1.020 as an indicator of proper hydration. According to the current WCP, if the Usg test is not passed (i.e., .1.020), the wrestler must be retested no sooner than 24 hours after the initial assessment. This delay is intended to allow the wrestler time for proper rehydration, yet acute fluid consumption may offer an alternative to expedite this process. Previous studies (7,12) have clearly demonstrated that relatively modest volumes of fluid (591–1,000 ml) can cause significant shifts in Usg after an overnight fast. Dixon et al. (12) observed significant reductions in Usg 60 minutes after drinking 591 ml of water (1.024 6 0.004 vs. 1.012 6 0.004) or a carbohydrate beverage (1.022 6 0.004 vs. 1.009 6 0.006). More recently, research has shown that the consumption of approximately 1,000 ml of water reduced Usg levels to an acceptable value (1.026 6 0.004 vs. 1.013 6 0.006) after a failed test and resulted in %BF and MWW values that were not significantly different than those observed .24 hours later in a hydrated state when following
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Journal of Strength and Conditioning Research the WCP 24 hours rule (7). These results suggest that acute fluid consumption may allow the wrestler and the assessor the opportunity to complete the weight certification process in a single day rather than waiting 24 hours as required by the WCP. Previous research (20,33,35) has shown that the consumption of large fluid volumes (.2,500 ml) after exercise may result in dilute urine, indicating euhydration when body mass has not yet been restored to preexercise (PRE) values. If acute fluid consumption is to be considered for use during the WCP, it is important to establish if a predetermined volume of water (1 L) is capable of producing dilute urine and reducing Usg among wrestlers experiencing exercise-induced fluid loss and body mass reduction. The primary purpose of this investigation was to determine the impact of acute fluid consumption equal to 1 L on Usg, body mass, %BF, and MWW following an exercise-induced fluid loss protocol in wrestlers using 4 different body composition methods of assessment. Although support of the effectiveness of the WCP exists (3,8,34), anecdotal evidence indicates that some wrestlers may use similar practices involving dehydration and acute fluid consumption to “trick” the current testing system in an attempt to establish a lower MWW. A secondary purpose of the present study was to determine NCAA coaches’ perceptions of the WCP including possible strategies that may be used by wrestlers to establish a lower MWW.
METHODS Experimental Approach to the Problem
Approximately 1 L of fluid has been shown to reduce Usg values among subjects completing an overnight fast (7); however, it is important to determine if the same fluid volume (1 L) could reduce Usg in a similar manner among wrestlers completing an exercise-induced fluid loss protocol. The loss of body mass experienced during exercise may result in lower predicted MWWs; therefore, it is important to determine if this procedure can potentially “trick” the system by reducing Usg in the presence of reduced body mass. Previous research (20,33,35) has shown that the rapid consumption of large fluid volumes equal to the body mass lost during exercise may result in an increased urine production. This urine may be dilute, indicating euhydration even when body mass has not been restored to preexercise levels. We hypothesized that a more modest volume of water (1 L) would be ineffective in producing dilute urine (reducing Usg) among subjects experiencing exercise-induced fluid loss and body mass reduction. Skinfolds (SF) and air displacement plethysmography (ADP) are both approved by the NCAA for use during the WCP and were used to determine %BF. Bioelectrical impedance may be considered for NCAA use and is currently used during high school weight certifications; therefore, leg-to-leg bioelectrical impedance analysis (LBIA) and multifrequency bioelectrical impedance analysis (MFBIA) were also used to assess %BF. A within-subject experimental design was used over 3 conditions: PRE, post-
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exercise (POST), and 1 hour after fluid consumption (PFC). A survey was also e-mailed to a stratified random sample of NCAA head coaches from Divisions I, II, and III to assess their satisfaction with the WCP and to inquire about the strategies that may be used by NCAA wrestlers to establish a lower MWW. Subjects
The present study was approved by The University of Scranton’s Institutional Review Board, and informed consent was obtained from each subject. Twelve male, NCAA division III wrestlers volunteered to participate in the present study. Subject characteristics, including age, height, body mass, and %BF, are presented in Table 1. Subjects were asked to refrain from alcohol and diuretic use 48 hours and 7 days, respectively, before testing. The participants’ bowel and bladder were both emptied before body composition analysis to limit the content’s influence on body mass. Surveys were e-mailed to a randomly selected group of head coaches to achieve a stratified random sample of coaches from Divisions I (n = 40), II (n = 20), and III (n = 40). A 48% response rate was achieved with 19, 9, and 19 coaches from Divisions I, II, and III, respectively, participating in the study. All surveys were anonymous and could not be tracked back to the respondent. Procedures
All measurements were performed on each wrestler during a single testing session, which included 3 assessments (PRE, POST, and PFC). Wrestlers were asked to maintain a normal diet on the day of testing and encouraged to consume fluids ad libitum to ensure that they would meet the NCAA hydration standards (Usg , 1.020). A typical 2-hour practice in the university’s wrestling room served as the dehydration protocol. Temperature in the wrestling room was maintained at normal operating temperatures (range, 23–278 C). The practice was under the direction of the team’s head coach and included drills, conditioning, and live wrestling at the discretion of the coach. Similar protocols have been
TABLE 1. Data obtained from PRE trial using SF (N = 12).* Subject characteristics Age Height (cm) BM (kg) %BF
Mean 6 SD 19.8 180.0 77.6 12.4
6 6 6 6
Minimum– maximum
1.14 18–21 8.10 168.92203.2 11.1 61.0298.8 2.35 9.3–16.5
*BM = body mass; %BF = percent body fat.
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Fluid Consumption and Minimum Wrestling Weight used previously by Utter et al. (39,41) who observed average body mass reduction equal to 2.0 and 2.5 kg, respectively. Experimental Session
Upon arriving to the exercise science laboratory, wrestlers underwent a PRE testing session, which included Usg and body composition assessments. The Usg test was conducted using a clinical refractometer (Atago PEN-Wrestling refractometer; Atago U.S.A., Inc., Bellevue, WA, USA). If the Usg was ,1.020, body composition was measured using 4 common methods of assessment: SF, ADP, LBIA, and MFBIA. The same assessments were repeated after practice (POST). After the POST assessment, each wrestler was asked to consume 1 L of bottled water (Poland Spring Natural Spring Water; Nestle´ Waters North America Inc., Stamford, CT, USA) in ,15 minutes. No other fluid was consumed between the PRE and PFC assessments. One hour PFC, Usg and body composition tests were completed for the final time. One hour has been shown to be adequate to observe a change in Usg in response to acute fluid consumption (7,12,33,41,42). Subjects refrained from urinating at any time during the study except for the assessment times noted above (PRE, POST, and PFC). Skinfolds
Subcutaneous adipose tissue was measured by an experienced certified athletic trainer at the triceps, subscapula, and abdomen using a SF caliper (Lange; Cambridge Scientific Industries, Inc., Cambridge, MD, USA). All SF were measured to the nearest 0.5 mm on the right side of the body. Each site was measured 3 times, with the median value recorded for analysis. The assessor had previous experience conducting SF in collegiate wrestlers and was familiar with NCAA WCP. Body density was determined from the SF measures using the prediction equation by Lohman (25): Body density ¼ 1:09822ð½sum of SF30:000815Þþð½sum of SF2 30:00000084Þ. The Lohman equation has been adopted by the NCAA for the calculation of body density from the SF measurement (28). The %BF was then estimated from body density using the equation by Brozek et al. (4): %BF ¼ ½ð4:57=body densityÞ24:1423100. Predicted MWW was then calculated as the body mass at 5% body fat representing the lowest allowable %BF under the WCP: MWW = lean body mass O 0.95. Air Displacement Plethysmography
The ADP (BOD POD Gold Standard Body Composition Tracking System, Life Measurement, Inc., Concord, CA, USA) measures body volume, as previously described (9). Before each test, the ADP was calibrated according to the manufacturer’s instructions using a cylinder of known volume (50.572 L). The subject, wearing only tight-fitting briefs and swim cap, then entered the chamber. The door was closed and the subjected breathed normally while 2 measurements of body volume were conducted, each lasting approximately 45 seconds. If these 2 body volumes differed
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by .150 ml, a third body volume measurement was performed. Thoracic gas volume was predicted using preprogrammed manufacturer equations. Body composition measurements have been shown to be similar when predicted or measured lung volume is used with ADP (27). Upon completion of the test, the computer automatically calculated %BF from the determined body density using the equation by Brozek et al. (4). Bioelectrical Impedance Analysis
Leg-to-leg bioelectrical impedance analysis measurements were determined using a leg-to-leg bioelectrical impedance analyzer (Tanita model TBF-300A; Tanita Corporation of America, Inc., Arlington Heights, IL, USA). Each subject, wearing only tight-fitting briefs, stood erect with bare feet placed properly on the contact electrodes of the LBIA instrument. As previously described (29), the LBIA system consists of 4 contact electrodes (2 anterior and 2 posterior) that are mounted on the surface of a platform scale. A lowenergy, single-frequency, electrical signal (500 mA, 50 kHz) is passed through the anterior electrode on the scale platform, and the voltage drop is measured on the posterior electrode. Lower-body impedance and body mass were measured simultaneously while the subject stood on the LBIA scale. The LBIA analyzer automatically calculated %BF using preprogrammed proprietary equations (athletic mode) developed by the manufacturer. Multifrequency bioelectrical impedance analysis measurements were performed using a multifrequency segmental bioelectrical impedance analyzer (InBody 520; Biospace, Inc., Beverly Hills, CA, USA). Each subject, wearing only tight-fitting briefs, stood erect holding the hand electrodes with bare feet placed properly on the contact electrodes of the MFBIA instrument. The MFBIA system consists of 4 tactile electrodes (2 anterior and 2 posterior) that are mounted on the surface of a platform scale, and each extremity handgrip has an anterior and a posterior electrodes. Measurements were carried out at 5, 50, and 500 kHz frequencies. The MFBIA analyzer automatically calculated %BF using preprogrammed proprietary equations developed by the manufacturer. Statistical Analyses
Data were analyzed using the SPSS Statistics 21 statistical package (IBM Corp., Armonk, NY, USA). The dependent variables (Usg, body mass, %BF, and MWW) were each analyzed using a repeated measures analysis of variance (ANOVA) to identify differences between the various conditions (PRE, POST, and PFC). Post hoc comparisons using a Bonferroni adjustment were used to identify differences when statistical significance was identified through the ANOVA. The MWWs predicted by each of the 4 methods at the PRE trial were compared through linear regression and assessment of the standard error of the estimate (SEE) when using ADP as the criterion. Statistical significance was set a priori at p , 0.05 for all tests. All data are presented as
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Journal of Strength and Conditioning Research mean 6 SD unless otherwise noted. The intraclass correlation coefficient for %BF was determined from the PRE and POST assessments. The values obtained for SF, ADP, LBIA, and MFBIA were 0.990, 0.877, 0.877, and 0.965, respectively.
RESULTS Descriptive characteristics of the wrestlers are presented in Table 1. The wrestlers lost an average of 2.4 6 0.5% in body mass equal to 1.9 6 0.5 kg during the 2-hour practice. Body mass was significantly less after exercise (POST) and 1 hour after fluid consumption (PFC) when compared with the PRE assessment (PRE = 77.6 6 11.1 kg; POST = 75.7 6 10.9 kg; PFC = 76.4 6 10.9 kg; p , 0.001). All wrestlers reported for testing properly hydrated according to NCAA standards (Usg , 1.020). Urine specific gravity measurements significantly increased above PRE (1.013 6 0.006) at the POST (1.019 6 0.007, p = 0.017) and PFC (1.022 6 0 0.008, p = 0.025) assessments. However, Usg at POST and PFC were not significantly different (p = 0.978). All of the subjects experienced an increase in Usg as a result of the exercise protocol; however, 6 of the 12 subjects would have passed the Usg test at the POST assessment (Usg , 1.020), despite the observed decreases in body mass. Of the 12 subjects, 10 experienced an increase in Usg at the PFC assessment, and all but 1 subject would have failed the Usg test (Usg . 1.020) at the PFC assessment, despite the consumption of 1 L of water. The 2 subjects who did experience a reduction in Usg at PFC lost the least amount of body mass during the exercise protocol (1.3 kg) and were the only subjects who lost ,2% of their PRE body mass (1.8 and 1.5%). Fluid consumption equal to 1 L was ineffective in reducing Usg levels below the NCAA WCP guideline (Usg , 1.020) after exercise-induced fluid loss exceeding 2% of the original body mass. As demonstrated in Table 2, the %BF values at each assessment point (PRE, POST, and PFC) were not significantly different when using SF and ADP methods. Conversely, %BF values were significantly less after exercise for both LBIA and MFBIA. As demonstrated in Table 3, MWW was significantly reduced at both the POST and PFC assessments when using SF and ADP methods. However, MWW was reduced for every subject at the POST assessment and increased at the PFC assessment when using these same methods (SF and ADP). This change in MWW reflected the change in body mass in response to exercise (observed decrease) and fluid consumption (observed increase). Despite similar responses in MWW for SF and ADP, the individual differences in MWW predicted by these 2 NCAA-approved methods ranged from 0.1 to 4.6 kg. When using MFBIA, the MWW was not significantly different between the 3 assessment periods, although MWW was significantly decreased during the POST assessment compared with PRE assessment when using LBIA. A decrease in MWW at the POST assessment was observed among 9 of the 12 subjects when using LBIA; however, the change in
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TABLE 2. Percent body fat (%BF) values presented as mean 6 SD (N = 12).* PRE (%) SF ADP MFBIA LBIA
12.4 13.3 13.3 10.3
6 6 6 6
2.4 3.4 3.4 3.3
POST (%) 12.2 13.5 10.9 8.9
6 6 6 6
2.4 3.6 3.0† 3.4†
PFC (%) 12.3 13.3 11.3 9.5
6 6 6 6
2.5 4.0 3.2† 3.2z
*SF = skinfold; ADP = air displacement plethysmography; LBIA = leg-to-leg bioelectrical impedance analysis; MFBIA = multifrequency bioelectrical impedance analysis; PRE = prepractice; POST = postpractice; PFC = 1 hour after fluid consumption. †Significant difference from the PRE trial (p # 0.05). zSignificant difference compared to both PRE and POST (p # 0.05).
MWW between the assessment periods did not reflect the change in body mass when using bioelectrical impedance (MFBIA and LBIA) as it did when using SF and ADP methods. A comparison of both %BF and MWW measurements determined by the 4 methods of assessment was performed using data from the PRE assessment. Leg-to-leg bioelectrical impedance analysis (10.3 6 3.3%) significantly underestimated %BF when compared with ADP (13.3 6 3.4%; p = 0.050) and MFBIA (13.3 6 3.4%; p = 0.033). For MWW, only LBIA (69.0 6 8.9 kg) was significantly different than MFBIA (66.5 6 8.9 kg; p = 0.031). When using ADP as the criterion, the SEE values for SF, MFBIA, and LBIA during the PRE assessment were 2.07, 3.22, and 2.82 kg, respectively. A summary of results from the survey of NCAA coaches is included in Table 4. The central themes that emerged were as follows: (a) Because of the rule limiting weight loss to
TABLE 3. Minimum wrestling weight (MWW) values presented as mean 6 SD (N = 12).* PRE (kg) SF ADP MFBIA LBIA
67.2 66.6 66.5 69.0
6 6 6 6
8.4 9.1 8.3 9.0
POST (kg) 65.7 64.8 66.8 68.4
6 6 6 6
8.2† 9.0† 8.6 8.8
PFC (kg) 66.3 65.6 67.1 68.6
6 6 6 6
8.0zs 9.3† 8.4 8.8†
*SF = skinfold; ADP = air displacement plethysmography; LBIA = leg-to-leg bioelectrical impedance analysis; MFBIA = multifrequency bioelectrical impedance analysis; PRE = prepractice; POST = postpractice; PFC = 1 hour after fluid consumption. †Significant difference from the PRE trial (p # 0.05). zSignificant difference compared to both PRE and POST (p # 0.05).
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Fluid Consumption and Minimum Wrestling Weight
TABLE 4. NCAA coaches’ survey responses (N = 47).* Question How long have you been coaching at the collegiate level? Please rate your overall satisfaction with the WCP?
If you are dissatisfied in anyway, please explain the circumstances. Please include any suggestions you might have to improve the WCP. Has the WCP ever restricted an athlete from reaching a lower weight class, which you thought was reasonably attainable? Please include suggestions to improve the WCP. Are you aware of any strategies that wrestlers might use to achieve a lower MWW during the WCP?
DI (n = 19)
DII (n = 9)
DIII (n = 19)
0–5 years 1 (5.3%) 2 (22.2%) 7 (36.8%) 6–10 years 7 (36.8%) 1 (11.1%) 6 (31.6%) 11–15 years 3 (15.8%) 1 (11.1%) 2 (10.5%) 16+ years 8 (42.1%) 5 (55.6%) 4 (21.1%) Very satisfied 2 (11.1%) 0 (0.0%) 2 (10.5%) Satisfied 5 (27.8%) 6 (66.7%) 9 (47.4%) Neutral 3 (16.7%) 0 (0.0%) 6 (31.6%) Dissatisfied 8 (44.4%) 1 (11.1%) 2 (10.5%) Very dissatisfied 0 (0.0%) 2 (22.2%) 0 (0.0%) Most common comments (the percentage of those respondents providing a comment to the question is included) 1. The 1.5% plan is unfair (33%) 2. Wrestlers and coaches have devised ways to get around the intent of the WCP (19%) 3. Allow recertification of MWW during the season (14%) Yes, 60% Most common comments in descending order 1. Allow recertification of MWW during the season (39%) No, 40% 2. The 1.5% weight loss plan is unfair (33%) 1. Super hydrate and then workout while holding their urine in an effort to pass the hydration test (49%) 2. Dehydrate to a weight below their desired weight and partially rehydrate in an effort to pass the hydration test (36%) 3. Drinking caffeinated beverages (17%)
*NCAA = National Collegiate Athletic Association; WCP = weight certification program; MWW = minimum wrestling weight.
1.5% body mass per week, wrestlers who wrestle up a weight class do not have ample time to lose weight and return to their original weight class before the next match, and (b) the notion that wrestlers use strategies in an attempt to circumvent the WCP in an effort to establish the lowest allowable MWW.
DISCUSSION Fluid consumption equal to 1 L of water following an exercise-induced fluid loss protocol failed to significantly reduce Usg levels. This finding is in opposition to previous studies that have demonstrated significant reductions in Usg after drinking similar fluid volumes following an overnight fast (7,12). The difference between the present and the aforementioned studies was the behavior that preceded fluid consumption. Previous studies examined fluid consumption after an overnight fast, whereas the present study examined fluid consumption after exercise-induced fluid loss. Exerciseinduced fluid loss significantly reduced body mass (21.9 6 0.48 kg) in the present study, stimulating fluid retention, which resulted in elevated Usg measurements at the PFC assessment. When examined individually, 11 of the 12 subjects would have failed the Usg test (Usg . 1.020) at 1-hour PFC. Furthermore, only 2 of the wrestlers experienced a decrease in Usg after fluid consumption, yet these wrestlers
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lost the least amount of body mass during the exercise session. The reduction in Usg observed among these subjects is not surprising because the fluid volume consumed after exercise more closely matched the fluid-loss experienced during the exercise protocol. Studies have shown that similar fluid volumes (0.6–1 L) have been effective in restoring euhydration (7,12,24); however, acute fluid consumption equal to 1 L of water appears to be ineffective in establishing euhydration among those experiencing exercise-induced fluid loss .2% of the original body mass. We have previously shown that 1 L of water can be used to restore euhydration (Usg , 1.020) while establishing MWWs that were not significantly different than if the assessment were repeated in a hydrated state more than 24 hours after a failed hydration test in accordance with the WCP (7). Rehydration is currently not permitted as part of the WCP; however, these studies support the use of partial rehydration if limited to 1 L immediately following a failed hydration test during the WCP. Because subjects in the present study were unable to reduce Usg through the use of a limited fluid volume, it is unlikely that wrestlers experiencing more severe levels of dehydration would be able to establish euhydration if the fluid volume were restricted to 1 L and the reassessment were offered at 1-hour PFC.
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Journal of Strength and Conditioning Research Currently, SF and ADP are both NCAA-approved methods of assessing %BF during the WCP. Interestingly, mean %BF values determined by these methods were unaffected by exercise and fluid consumption. Conversely, the LBIA and MFBIA technology, which is not approved by the NCAA, demonstrated significant reductions in the %BF values during the POST and PFC assessments compared with the PRE assessment. Previous studies have shown that exercise reduces impedance measured with LBIA and MFBIA, thus lowering %BF estimations (1,10,11). A possible explanation for the decreased impedance may be an increase in muscle perfusion (22) and skin temperature (5), which has been reported after exercise. Another concern related to this technology is that acute fluid consumption increases %BF as a result of increases in body mass and impedance (7,12,13). Whole-body impedance has been shown to increase when fluid is shifted away from the extremities and toward the trunk (12,32,36). It has been postulated that the blood may be redistributed from the periphery to the core in response to fluid entering the stomach and gastrointestinal tract (15), which might explain the increased %BF observed at the PFC assessment. The significant alterations in %BF observed in the present study during the POST and PFC assessments support previous findings related to LBIA and MFBIA (1,7,10–13). The exercise protocol used in the present study resulted in significant reductions in body mass, although %BF values remained unchanged when using both SF and ADP methods. This resulted in MWWs that reflected the change in body mass during the 3 assessment periods and support previous studies identifying body mass as a more important determinant of MWW when compared with %BF (3,7). Although body mass and exercise-induced fluid loss must be controlled during the determination of MWW, it appears that the method of assessment may be as equally important when predicting MWW. An examination of the SEEs revealed that SF- and ADP-predicted MWWs were within approximately 2.0 kg of one another at 68% of the time. Bartok et al. (3) observed a total error of 2.15 kg for MWW when SF was compared with a 4-component body composition assessment criterion (4-C). In a separate study, an evaluation of SF, hydrostatic weighing, and bioelectrical impedance compared with the 4-C method yielded SEEs of 1.72, 1.31, and 2.98 kg, respectively (6). The SF method seems very favorable in comparison to alternate methods, yet we observed differences in MWW determined by SF and ADP methods ranging from 0.09 to 4.61 kg for individual wrestlers. Although both methods are approved by the NCAA, it is important to note that a difference of 4.6 kg could result in a MWW 2 weight classes lower depending on the assessment method used. A 4.6 kg difference was observed in the present study for a 73 kg wrestler. Should a team have access to more than 1 NCAA-approved method, this variability could provide an advantage, albeit a legal one, in which a wrestler may be tested using multiple
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methods and then select the results from the one yielding the lowest MWW. If a 4-kg difference can be observed between 2 approved assessment methods, it is understandable why coaches become frustrated when wrestlers are ineligible for certain weight classes by fractions of a kilogram. When the predicted MWW of the alternate methods was compared with ADP, MFBIA and LBIA exhibited slightly greater error estimates (3.22 kg and 2.82 kg, respectively) than SF (2.07 kg) in the present study. Skinfold measurements have often been shown to have lower SEE values compared with LBIA (6,40) or MFBIA (38) when using hydrostatic weighing or 4-C as the criterion. Similar error estimates (1.51–2.34 kg) have also been reported when LBIA was compared with SF to assess MWW among high school wrestlers (17), suggesting that these methods should not be used interchangeably. Our results are similar to those of Clark et al. (6) where the standard error for bioelectrical impedance was the greatest, and although we failed to observe a significant difference between the mean MWW for LBIA when compared with both SF and ADP methods, the SEEs associated with bioelectrical impedance (LBIA and MFBIA) in addition to its sensitivity to changes in hydration status and fluid shifts have likely resulted in the exclusion of bioelectrical impedance as an NCAA-approved method. The intent of the survey administered to NCAA coaches was to identify the perceptions of coaches toward the WCP and to inquire about possible strategies that may be used in an effort to establish a lower MWW. When asked about their overall satisfaction with the WCP, 53% of the respondents were either “very satisfied” or “satisfied” with the WCP. The most frequently cited concern that coaches identified with the WCP was the rule that limits wrestlers to a weight loss equal to 1.5% of body mass per week. This may pose concerns for the coach because a wrestler who competes and weighs-in near the limit of the next higher weight class would be unable to return to their original weight class the following week because of the 1.5% weight loss limit. Coaches stated that the only way to avoid this issue is to have the individual wrestle up against a heavier opponent while maintaining their normal (lower) weight. The 1.5% weight loss per week is included in the WCP to prevent the rapid, unhealthy weight loss practices common among wrestlers (37). However, any weight loss exceeding 1.5% per week should also be a concern of the coach given its potential adverse relationship on performance. The research surrounding weight loss and performance is inconsistent. Weight loss of approximately 3–5% body mass has been associated with decreased strength and anaerobic performance among wresters (43,44), while other studies have failed to show a change in anaerobic performance when weight loss was equal to 4–6% body mass (14,26). These conflicting results are likely related to the different methodologies used within the studies, but a thorough review conducted by Lambert and Jones (23) addressed the performance deficits associated with weight loss and concluded VOLUME 28 | NUMBER 7 | JULY 2014 |
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Fluid Consumption and Minimum Wrestling Weight that dehydration of 3–4% of body mass impairs muscular endurance and occurs whether the weight loss is rapid or spread out gradually over several days. These data citing performance decrements after weight loss exceeding 3% may lead to the skepticism among coaches questioning the 1.5% rule. However, if athletes are still using rapid weight loss strategies even after the implementation of the WCP as suggested by coaches, a conservative 1.5% will likely remain in an effort to ensure athlete safety and reduce the risk of unhealthy and often dangerous weight-loss procedures. The coaches in the present study identified 3 strategies that may be used by a wrestler to pass the hydration test to establish a lower MWW. The first strategy was reducing one’s weight through exercise and dehydration followed by fluid consumption equal to a volume less than that lost through dehydration, thus allowing the athlete to pass the hydration test and establish a lower MWW. Thirty-six percent of coaches surveyed in the present study indicated that they were aware of a strategy involving exercise-induced dehydration followed by partial rehydration. During this process, wrestlers deliberately dehydrate themselves and consume fluid volumes less than that lost during dehydration to establish a lower MWW. The theory behind this strategy is likely based on the research that has suggested that the rapid consumption of fluid may produce diluted urine samples through a diuretic response and the production of excess urine (35). Similar studies on rehydrating subjects with fluid volumes equal to that lost during dehydration have also shown that Usg may indicate euhydration when, in fact, body mass has not been restored to PRE values (20,33), likely because of excess urine production. Although Usg values have been returned to baseline within 1 hour of consuming water equal to the body mass lost during dehydration (41,42), such a volume load would be counterproductive if the intent were to artificially reduce body mass in the hope of lowering one’s MWW. The present study failed to identify a difference in Usg between the POST and PFC assessments. Therefore, these data do not support the strategy involving exercise-induced fluid loss followed by partial rehydration. It is important to note that the subjects in the present study did not experience the same level of severe dehydration that may be present among wrestlers. Furthermore, fluid consumption was limited to 1 L; therefore, it is possible that more severe levels of dehydration and larger fluid volumes may be used to “trick” the system by establishing acceptable Usg values along with reduced body mass. Future research is warranted in this area. A second strategy identified by coaches was drinking excess fluid or hyperhydrating and then holding urine during exercise-induced fluid loss until the Usg test. The expectation is that the urine will be dilute and not representative of actual hydration status at the time of testing, allowing them to pass the hydration test. The process of hyperhydrating before exercise and holding one’s urine until the hydration assessment is not tested presently. However, 49% of the
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coaches surveyed were aware of this strategy. Although not a purpose of the present investigation, the Usg, %BF, and MWW data at the POST assessment provides preliminary evidence that despite exercise-induced reductions in body mass, Usg values may remain below NCAA WCP standards. As such, if one holds their urine between exercise and the hydration test, it may be possible that the urine remaining in the bladder after exercise is dilute enough to pass the Usg assessment. This finding in the present study where Usg was lower at POST than at PFC assessment supports a potential limitation to Usg as a measure of hydration status because it has been shown to lag behind more time sensitive measures such as plasma osmolality (31,33,41). Although 1 hour has been shown to be adequate time to identify changes in Usg in response to acute fluid consumption (7,12,33,41,42), Usg testing was done immediately after exercise and may not have accurately reflected the subjects’ hydration status at the POST assessment because of urine holding. Again, this is only preliminary and the impact of more extreme dehydration and its effect on “urine holding” as a potential strategy to “trick” the WCP are still undefined and warrant further investigation. The final strategy identified by coaches included the consumption of caffeinated beverages before the hydration test in an attempt to produce diluted urine to pass the hydration test. Although caffeine use was not examined in the present study, the proposition that caffeine may be helpful in allowing one to pass the hydration test more easily may have little merit given that caffeinated beverages have been shown to have no effect on Usg (2,16), yet this has not been studied in direct relationship to the WCP.
PRACTICAL APPLICATIONS To complete body composition testing given the current WCP, the wrestler’s Usg must be ,1.020. The hydration guidelines are useful in preventing dehydration, which may be used to reduce body mass in an attempt to establish a lower MWW. In accordance with the WCP, a wrestler failing the initial hydration assessment must wait a minimum of 24 hours to be retested, placing increased time demands on the personnel responsible for this testing. Acute fluid consumption (approximately 1 L of water) has been previously shown to decrease Usg to an acceptable level (,1.020) among subjects dehydrated (Usg . 1.020) after an overnight fast (7). In the same study, MWW was no different after acute fluid consumption than when the subject waited 24 hours after a failed hydration test as required by the WCP. The use of acute rehydration may offer an alternative during the WCP rather than waiting 24 hours for reassessment; however, it was important to determine if a similar fluid volume could be used to establish euhydration among those experiencing exercise-induced fluid loss, thus “tricking” the system in an effort to establish a lower MWW. In the present study, Usg was not reduced 1 hour after fluid consumption, as it was among those completing an overnight fast; therefore,
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Journal of Strength and Conditioning Research it seems that if water consumption is limited to 1 L after a failed test and Usg is reexamined 1 hour later, euhydration is unlikely among those who have significantly reduced their body mass through exercise-induced fluid loss. Together, these studies suggest that acute fluid consumption limited to 1 L may be effective in reducing Usg and restoring euhydration among those not experiencing exercise-induced fluid loss, although it would be ineffective in restoring euhydration among those who have experienced exercise-induced fluid loss. Given this evidence, acute fluid consumption equal to 1 L may offer an alternative to expedite the WCP after a failed hydration test among those not experiencing exerciseinduced fluid loss when using SF and ADP. Furthermore, athlete safety would not be compromised, as those experiencing deliberate exercise-induced fluid loss would be unable to establish euhydration when using a limited volume of water (1 L). The present study also provides novel insight into the use of deliberate strategies, which may be used by wrestlers in an attempt to circumvent the WCP in an attempt to establish a lower MWW. Although athletes may attempt to use strategies such as fluid consumption after exercise or urine holding, it is important to note that none of the strategies mentioned here have been proven to be effective in establishing lower MWWs. Furthermore, any attempt at using exercise-induced fluid loss strategies uses an inherent danger and should be avoided. Additional researches examining the various strategies that may be used by wrestlers in an effort to “trick” the system are warranted in an effort to maintain the safety of the athlete during the WCP.
ACKNOWLEDGMENTS
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6. Clark, RR, Bartok, C, Sullivan, JC, and Schoeller, DA. Minimum weight prediction methods cross-validated by the four-component model. Med Sci Sports Exerc 36: 639–647, 2004. 7. Cutrufello, PT and Dixon, CB. The effect of acute fluid consumption and hydration status on percent body fat and minimum wrestling weight. J Strength Cond Res 27: 1950–1957, 2013. 8. Davis, SE, Dwyer, GB, Reed, K, Bopp, C, Stosic, J, and Shepanski, M. Preliminary investigation: The impact of the NCAA wrestling weight certification program on weight cutting. J Strength Cond Res 16: 305–307, 2002. 9. Dempster, P and Aitkens, S. A new air displacement method for the determination of human body composition. Med Sci Sports Exerc 27: 1692–1697, 1995. 10. Demura, S, Yamaji, S, Goshi, F, and Nagasawa, Y. The influence of transient change of total body water on relative body fats based on three bioelectrical impedance analyses methods. Comparison between before and after exercise with sweat loss, and after drinking. J Sports Med Phys Fitness 42: 38–44, 2002. 11. Dixon, CB and Andreacci, JL. Effect of resistance exercise on percent body fat using leg-to-leg and segmental bioelectrical impedance analysis in adults. J Strength Cond Res 23: 2025–2032, 2009. 12. Dixon, CB, LoVallo, SJ, Andreacci, JL, and Goss, FL. The effect of acute fluid consumption on measures of impedance and percent body fat using leg-to-leg bioelectrical impedance analysis. Eur J Clin Nutr 60: 142–146, 2006. 13. Dixon, CB, Ramos, L, Fitzgerald, E, Reppert, D, and Andreacci, JL. The effect of acute fluid consumption on measures of impedance and percent body fat estimated using segmental bioelectrical impedance analysis. Eur J Clin Nutr 63: 1115–1122, 2009. 14. Fogelholm, GM, Koskinen, R, Laakso, J, Rankinen, T, and Ruokonen, I. Gradual and rapid weight loss: Effects on nutrition and performance in male athletes. Med Sci Sports Exerc 25: 371–377, 1993. 15. Gomez, T, Mole, PA, and Colins, A. Dilution of body fluid electrolytes affects bioelectrical impedance measurements. Sports Med Train Rehabil 4: 291–298, 1993.
The authors express their gratitude to Emily Mossler and Stephen Gadomski for their assistance during the data collection process. This study was funded through an internal research grant from The University of Scranton. The authors have no conflict of interest to declare. The results of this study do not constitute the endorsement of any product by the authors or the National Strength and Conditioning Association.
16. Grandjean, AC, Reimers, KJ, Bannick, KE, and Haven, MC. The effect of caffeinated, non-caffeinated, caloric and non-caloric beverages on hydration. J Am Coll Nutr 19: 591–600, 2000.
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17. Hetzler, RK, Kimura, IF, Haines, K, Labotz, M, and Smith, J. A comparison of bioelectrical impedance and skinfold measurements in determining minimum wrestling weights in high school wrestlers. J Athl Train 41: 46–51, 2006. 18. Hoey, J. Wrestling hyperthermia and dehydration. CMAJ 158: 1171–1172, 1998.
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2. Armstrong, LE, Pumerantz, AC, Roti, MW, Judelson, DA, Watson, G, Dias, JC, Sokmen, B, Casa, DJ, Maresh, CM, Lieberman, H, and Kellogg, M. Fluid, electrolyte, and renal indices of hydration during 11 days of controlled caffeine consumption. Int J Sport Nutr Exerc Metab 15: 252–265, 2005.
21. Kraemer, WJ, Fry, AC, Rubin, MR, Triplett-McBride, T, Gordon, SE, Koziris, LP, Lynch, JM, Volek, JS, Meuffels, DE, Newton, RU, and Fleck, SJ. Physiological and performance responses to tournament wrestling. Med Sci Sports Exerc 33: 1367–1378, 2001.
3. Bartok, C, Schoeller, DA, Randall Clark, R, Sullivan, JC, and Landry, GL. The effect of dehydration on wrestling minimum weight assessment. Med Sci Sport Exerc 36: 160–167, 2004.
22. Kushner, RF, Gudivaka, R, and Schoeller, DA. Clinical characteristics influencing bioelectrical impedance analysis measurements. Am J Clin Nutr 64: 423S–427S, 1996.
4. Brozek, J, Grande, F, Anderson, JT, and Keys, A. Densitometric analysis of body composition: Revision of some quantitative assumptions. Ann NY Acad Sci 110: 113–140, 1963.
23. Lambert, C and Jones, B. Alternatives to rapid weight loss in US wrestling. Int J Sports Med 31: 523–528, 2010.
5. Caton, JR, Mole, PA, Adams, WC, and Heustis, DS. Body composition analysis by bioelectrical impedance: Effect of skin temperature. Med Sci Sports Exerc 20: 489–491, 1988.
24. Logan-Sprenger, HM and Spriet, LL. The acute effects of fluid intake on urine specific gravity and fluid retention in a mildly dehydrated state. J Strength Cond Res 27: 1002–1008, 2013. VOLUME 28 | NUMBER 7 | JULY 2014 |
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Fluid Consumption and Minimum Wrestling Weight 25. Lohman, TG. Skinfolds and body density and their relation to body fatness: A review. Hum Biol 53: 181–225, 1981. 26. Marttinen, RH, Judelson, DA, Wiersma, LD, and Coburn, JW. Effects of self-selected mass loss on performance and mood in collegiate wrestlers. J Strength Cond Res 25: 1010–1015, 2011. 27. McCrory, MA, Mole, PA, Gomez, TD, Dewey, KG, and Bernauer, EM. Body composition by air-displacement plethysmography by using predicted and measured thoracic gas volumes. J Appl Physiol (1985) 84: 1475–1479, 1998. 28. National Collegiate Athletic Association. National NCAA Wrestling Weight Management Program for 2011-12. Available at: http:// www.naia.org/fls/27900/1NAIA/Championships/ CoachesCorner/Wrestling/WR_WeightManagementProgram.pdf? DB_OEM_ID=27900. Accessed February 23, 2012. 29. Nunez, C, Gallagher, D, Visser, M, Pi-Sunyer, FX, Wang, Z, and Heymsfield, SB. Bioimpedance analysis: Evaluation of leg-to-leg system based on pressure contact footpad electrodes. Med Sci Sports Exerc 29: 524–531, 1997. 30. Oppliger, RA, Landry, GL, Foster, SW, and Lambrecht, AC. Bulimic behaviors among interscholastic wrestlers: A statewide survey. Pediatrics 91: 826–831, 1993. 31. Oppliger, RA, Magnes, SA, Popowski, LA, and Gisolfi, CV. Accuracy of urine specific gravity and osmolality as indicators of hydration status. Int J Sport Nutr Exerc 15: 236–251, 2005. 32. Oshima, Y and Shiga, T. Within-day variability of whole-body and segmental bioelectrical impedance in a standing position. Eur J Clin Nutr 60: 938–941, 2006. 33. Popowski, LA, Oppliger, RA, Patrick Lambert, G, Johnson, RF, Kim Johnson, A, and Gisolf, CV. Blood and urinary measures of hydration status during progressive acute dehydration. Med Sci Sports Exerc 33: 747–753, 2001. 34. Ransone, J and Hughes, B. Body-weight fluctuation in collegiate wrestlers: Implications of the National Collegiate Athletic Association weight-certification program. J Athl Train 39: 162–168, 2004.
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35. Shirreffs, SM, Taylor, AJ, Leiper, JB, and Maughan, RJ. Post-exercise rehydration in man: Effects of volume consumed and drink sodium content. Med Sci Sports Exerc 28: 1260–1271, 1996. 36. Slinde, F, Bark, A, Jansson, J, and Rossander-Hulthen, L. Bioelectrical impedance variation in healthy subjects during 12 h in the supine position. Clin Nutr 22: 153–157, 2003. 37. Turocy, PS, DePalma, BF, Horswill, CA, Laquale, KM, Martin, TJ, Perry, AC, Somova, MJ, and Utter, AC. National Athletic Trainers’ Association position statement: Safe weight loss and maintenance practices in sport and exercise. J Athl Train 46: 322–336, 2011. 38. Utter, AC and Lambeth, PG. Evaluation of multifrequency bioelectrical impedance analysis in assessing body composition of wrestlers. Med Sci Sports Exerc 42: 361–367, 2010. 39. Utter, AC, Goss, FL, Swan, PD, Harris, GS, Robertson, RJ, and Trone, GA. Evaluation of air displacement for assessing body composition of collegiate wrestlers. Med Sci Sports Exerc 35: 500–505, 2003. 40. Utter, AC, Nieman, DC, Mulford, GJ, Tobin, R, Schumm, S, McInnis, T, and Monk, JR. Evaluation of leg-to-leg BIA in assessing body composition of high-school wrestlers. Med Sci Sports Exerc 37: 1395–1400, 2005. 41. Utter, AC, Quindry, JC, Emerenziani, GP, and Valiente, JS. Effects of rooibos tea, bottled water, and a carbohydrate beverage on blood and urinary measures of hydration after acute dehydration. Res Sports Med 18: 85–96, 2010. 42. Valiente, JS, Utter, AC, Quindry, JC, and Nieman, DC. Effects of commercially formulated water on the hydration status of dehydrated collegiate wrestlers. J Strength Cond Res 23: 2210–2216, 2009. 43. Webster, S, Rutt, R, and Weltman, A. Physiological effects of a weight loss regimen practiced by college wrestlers. Med Sci Sports Exerc 22: 229–234, 1990. 44. Wenos, DL and Amato, HK. Weight cycling alters muscular strength and endurance, ratings of perceived exertion, and total body water in college wrestlers. Percept Mot Skills 87: 975–978, 1998.
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AND
CURT B. DIXON2
1
Department of Exercise Science and Sport, The University of Scranton, Scranton, Pennsylvania; and 2Health Science Department, Lock Haven University, Lock Haven, Pennsylvania ABSTRACT
Cutrufello, PT and Dixon, CB. The effect of acute fluid consumption following exercise-induced fluid loss on hydration status, percent body fat, and minimum wrestling weight in wrestlers. J Strength Cond Res 28(7): 1928–1936, 2014— Acute fluid consumption (approximately 1 L) has been shown to reduce urine specific gravity (Usg) among subjects after an overnight fast, yet it is unknown if Usg may be reduced among subjects who have experienced exercise-induced fluid loss. The purpose of this study was to examine the effect of acute fluid consumption on Usg, body mass, percent body fat (%BF), and minimum wrestling weight (MWW) following an exerciseinduced fluid loss protocol. National Collegiate Athletic Association coaches’ perceptions of the weight certification program (WCP) were also evaluated. Twelve men wrestlers (19.8 6 1.14 years) were tested prepractice (PRE), postpractice (POST), and 1 hour after consuming 1 L of water (PFC). Percent body fat was measured by skinfolds (SF), air displacement plethysmography (ADP), and multifrequency and leg-to-leg bioelectrical impedance analysis to calculate MWW. Urine specific gravity measurements significantly increased above PRE (1.013 6 0.006) at the POST (1.019 6 0.007; p = 0.017) and PFC (1.022 6 0.008; p = 0.025) assessments; however, POST and PFC were not significantly different (p = 0.978) from one another. The %BF values were similar (p . 0.05) at each assessment point when using SF and ADP. When compared with PRE, MWW significantly reduced at the POST assessment when using SF (67.2 6 8.4 vs. 65.7 6 8.2 kg; p , 0.001) and ADP (66.6 6 9.1 vs. 64.8 6 9.0 kg; p = 0.001), reflecting the reduction in body mass observed after exercise. Forty-seven National Collegiate Athletic Association coaches completed the questionnaire and 2 central Address correspondence to Paul T. Cutrufello, paul.cutrufello@scranton. edu. 28(7)/1928–1936 Journal of Strength and Conditioning Research Ó 2014 National Strength and Conditioning Association
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themes emerged: (a) concerns with the 1.5% weight loss plan and (b) wrestlers using strategies in an attempt to circumvent the WCP. Exercise-induced fluid loss followed by acute fluid consumption equal to 1 L was ineffective in reducing Usg.
KEY
WORDS
specific gravity, impedance, plethysmography
skinfold,
bioelectrical
INTRODUCTION
I
n response to the unfortunate deaths of 3 collegiate wrestlers in 1997, related to rapid weight loss and intentional dehydration (18), the National Collegiate Athletic Association (NCAA) implemented a wrestling weight certification program (WCP) during the 1998– 1999 season (28). The WCP is designed to reduce the unhealthy weight loss practices that have been reported in the sport of wrestling (19,21,30). As part of the WCP, the NCAA requires that each wrestler have their percent body fat (%BF) determined preseason while properly hydrated to establish a minimum wrestling weight (MWW). The NCAA has defined urine specific gravity (Usg) , 1.020 as an indicator of proper hydration. According to the current WCP, if the Usg test is not passed (i.e., .1.020), the wrestler must be retested no sooner than 24 hours after the initial assessment. This delay is intended to allow the wrestler time for proper rehydration, yet acute fluid consumption may offer an alternative to expedite this process. Previous studies (7,12) have clearly demonstrated that relatively modest volumes of fluid (591–1,000 ml) can cause significant shifts in Usg after an overnight fast. Dixon et al. (12) observed significant reductions in Usg 60 minutes after drinking 591 ml of water (1.024 6 0.004 vs. 1.012 6 0.004) or a carbohydrate beverage (1.022 6 0.004 vs. 1.009 6 0.006). More recently, research has shown that the consumption of approximately 1,000 ml of water reduced Usg levels to an acceptable value (1.026 6 0.004 vs. 1.013 6 0.006) after a failed test and resulted in %BF and MWW values that were not significantly different than those observed .24 hours later in a hydrated state when following
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Journal of Strength and Conditioning Research the WCP 24 hours rule (7). These results suggest that acute fluid consumption may allow the wrestler and the assessor the opportunity to complete the weight certification process in a single day rather than waiting 24 hours as required by the WCP. Previous research (20,33,35) has shown that the consumption of large fluid volumes (.2,500 ml) after exercise may result in dilute urine, indicating euhydration when body mass has not yet been restored to preexercise (PRE) values. If acute fluid consumption is to be considered for use during the WCP, it is important to establish if a predetermined volume of water (1 L) is capable of producing dilute urine and reducing Usg among wrestlers experiencing exercise-induced fluid loss and body mass reduction. The primary purpose of this investigation was to determine the impact of acute fluid consumption equal to 1 L on Usg, body mass, %BF, and MWW following an exercise-induced fluid loss protocol in wrestlers using 4 different body composition methods of assessment. Although support of the effectiveness of the WCP exists (3,8,34), anecdotal evidence indicates that some wrestlers may use similar practices involving dehydration and acute fluid consumption to “trick” the current testing system in an attempt to establish a lower MWW. A secondary purpose of the present study was to determine NCAA coaches’ perceptions of the WCP including possible strategies that may be used by wrestlers to establish a lower MWW.
METHODS Experimental Approach to the Problem
Approximately 1 L of fluid has been shown to reduce Usg values among subjects completing an overnight fast (7); however, it is important to determine if the same fluid volume (1 L) could reduce Usg in a similar manner among wrestlers completing an exercise-induced fluid loss protocol. The loss of body mass experienced during exercise may result in lower predicted MWWs; therefore, it is important to determine if this procedure can potentially “trick” the system by reducing Usg in the presence of reduced body mass. Previous research (20,33,35) has shown that the rapid consumption of large fluid volumes equal to the body mass lost during exercise may result in an increased urine production. This urine may be dilute, indicating euhydration even when body mass has not been restored to preexercise levels. We hypothesized that a more modest volume of water (1 L) would be ineffective in producing dilute urine (reducing Usg) among subjects experiencing exercise-induced fluid loss and body mass reduction. Skinfolds (SF) and air displacement plethysmography (ADP) are both approved by the NCAA for use during the WCP and were used to determine %BF. Bioelectrical impedance may be considered for NCAA use and is currently used during high school weight certifications; therefore, leg-to-leg bioelectrical impedance analysis (LBIA) and multifrequency bioelectrical impedance analysis (MFBIA) were also used to assess %BF. A within-subject experimental design was used over 3 conditions: PRE, post-
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exercise (POST), and 1 hour after fluid consumption (PFC). A survey was also e-mailed to a stratified random sample of NCAA head coaches from Divisions I, II, and III to assess their satisfaction with the WCP and to inquire about the strategies that may be used by NCAA wrestlers to establish a lower MWW. Subjects
The present study was approved by The University of Scranton’s Institutional Review Board, and informed consent was obtained from each subject. Twelve male, NCAA division III wrestlers volunteered to participate in the present study. Subject characteristics, including age, height, body mass, and %BF, are presented in Table 1. Subjects were asked to refrain from alcohol and diuretic use 48 hours and 7 days, respectively, before testing. The participants’ bowel and bladder were both emptied before body composition analysis to limit the content’s influence on body mass. Surveys were e-mailed to a randomly selected group of head coaches to achieve a stratified random sample of coaches from Divisions I (n = 40), II (n = 20), and III (n = 40). A 48% response rate was achieved with 19, 9, and 19 coaches from Divisions I, II, and III, respectively, participating in the study. All surveys were anonymous and could not be tracked back to the respondent. Procedures
All measurements were performed on each wrestler during a single testing session, which included 3 assessments (PRE, POST, and PFC). Wrestlers were asked to maintain a normal diet on the day of testing and encouraged to consume fluids ad libitum to ensure that they would meet the NCAA hydration standards (Usg , 1.020). A typical 2-hour practice in the university’s wrestling room served as the dehydration protocol. Temperature in the wrestling room was maintained at normal operating temperatures (range, 23–278 C). The practice was under the direction of the team’s head coach and included drills, conditioning, and live wrestling at the discretion of the coach. Similar protocols have been
TABLE 1. Data obtained from PRE trial using SF (N = 12).* Subject characteristics Age Height (cm) BM (kg) %BF
Mean 6 SD 19.8 180.0 77.6 12.4
6 6 6 6
Minimum– maximum
1.14 18–21 8.10 168.92203.2 11.1 61.0298.8 2.35 9.3–16.5
*BM = body mass; %BF = percent body fat.
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Fluid Consumption and Minimum Wrestling Weight used previously by Utter et al. (39,41) who observed average body mass reduction equal to 2.0 and 2.5 kg, respectively. Experimental Session
Upon arriving to the exercise science laboratory, wrestlers underwent a PRE testing session, which included Usg and body composition assessments. The Usg test was conducted using a clinical refractometer (Atago PEN-Wrestling refractometer; Atago U.S.A., Inc., Bellevue, WA, USA). If the Usg was ,1.020, body composition was measured using 4 common methods of assessment: SF, ADP, LBIA, and MFBIA. The same assessments were repeated after practice (POST). After the POST assessment, each wrestler was asked to consume 1 L of bottled water (Poland Spring Natural Spring Water; Nestle´ Waters North America Inc., Stamford, CT, USA) in ,15 minutes. No other fluid was consumed between the PRE and PFC assessments. One hour PFC, Usg and body composition tests were completed for the final time. One hour has been shown to be adequate to observe a change in Usg in response to acute fluid consumption (7,12,33,41,42). Subjects refrained from urinating at any time during the study except for the assessment times noted above (PRE, POST, and PFC). Skinfolds
Subcutaneous adipose tissue was measured by an experienced certified athletic trainer at the triceps, subscapula, and abdomen using a SF caliper (Lange; Cambridge Scientific Industries, Inc., Cambridge, MD, USA). All SF were measured to the nearest 0.5 mm on the right side of the body. Each site was measured 3 times, with the median value recorded for analysis. The assessor had previous experience conducting SF in collegiate wrestlers and was familiar with NCAA WCP. Body density was determined from the SF measures using the prediction equation by Lohman (25): Body density ¼ 1:09822ð½sum of SF30:000815Þþð½sum of SF2 30:00000084Þ. The Lohman equation has been adopted by the NCAA for the calculation of body density from the SF measurement (28). The %BF was then estimated from body density using the equation by Brozek et al. (4): %BF ¼ ½ð4:57=body densityÞ24:1423100. Predicted MWW was then calculated as the body mass at 5% body fat representing the lowest allowable %BF under the WCP: MWW = lean body mass O 0.95. Air Displacement Plethysmography
The ADP (BOD POD Gold Standard Body Composition Tracking System, Life Measurement, Inc., Concord, CA, USA) measures body volume, as previously described (9). Before each test, the ADP was calibrated according to the manufacturer’s instructions using a cylinder of known volume (50.572 L). The subject, wearing only tight-fitting briefs and swim cap, then entered the chamber. The door was closed and the subjected breathed normally while 2 measurements of body volume were conducted, each lasting approximately 45 seconds. If these 2 body volumes differed
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by .150 ml, a third body volume measurement was performed. Thoracic gas volume was predicted using preprogrammed manufacturer equations. Body composition measurements have been shown to be similar when predicted or measured lung volume is used with ADP (27). Upon completion of the test, the computer automatically calculated %BF from the determined body density using the equation by Brozek et al. (4). Bioelectrical Impedance Analysis
Leg-to-leg bioelectrical impedance analysis measurements were determined using a leg-to-leg bioelectrical impedance analyzer (Tanita model TBF-300A; Tanita Corporation of America, Inc., Arlington Heights, IL, USA). Each subject, wearing only tight-fitting briefs, stood erect with bare feet placed properly on the contact electrodes of the LBIA instrument. As previously described (29), the LBIA system consists of 4 contact electrodes (2 anterior and 2 posterior) that are mounted on the surface of a platform scale. A lowenergy, single-frequency, electrical signal (500 mA, 50 kHz) is passed through the anterior electrode on the scale platform, and the voltage drop is measured on the posterior electrode. Lower-body impedance and body mass were measured simultaneously while the subject stood on the LBIA scale. The LBIA analyzer automatically calculated %BF using preprogrammed proprietary equations (athletic mode) developed by the manufacturer. Multifrequency bioelectrical impedance analysis measurements were performed using a multifrequency segmental bioelectrical impedance analyzer (InBody 520; Biospace, Inc., Beverly Hills, CA, USA). Each subject, wearing only tight-fitting briefs, stood erect holding the hand electrodes with bare feet placed properly on the contact electrodes of the MFBIA instrument. The MFBIA system consists of 4 tactile electrodes (2 anterior and 2 posterior) that are mounted on the surface of a platform scale, and each extremity handgrip has an anterior and a posterior electrodes. Measurements were carried out at 5, 50, and 500 kHz frequencies. The MFBIA analyzer automatically calculated %BF using preprogrammed proprietary equations developed by the manufacturer. Statistical Analyses
Data were analyzed using the SPSS Statistics 21 statistical package (IBM Corp., Armonk, NY, USA). The dependent variables (Usg, body mass, %BF, and MWW) were each analyzed using a repeated measures analysis of variance (ANOVA) to identify differences between the various conditions (PRE, POST, and PFC). Post hoc comparisons using a Bonferroni adjustment were used to identify differences when statistical significance was identified through the ANOVA. The MWWs predicted by each of the 4 methods at the PRE trial were compared through linear regression and assessment of the standard error of the estimate (SEE) when using ADP as the criterion. Statistical significance was set a priori at p , 0.05 for all tests. All data are presented as
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Journal of Strength and Conditioning Research mean 6 SD unless otherwise noted. The intraclass correlation coefficient for %BF was determined from the PRE and POST assessments. The values obtained for SF, ADP, LBIA, and MFBIA were 0.990, 0.877, 0.877, and 0.965, respectively.
RESULTS Descriptive characteristics of the wrestlers are presented in Table 1. The wrestlers lost an average of 2.4 6 0.5% in body mass equal to 1.9 6 0.5 kg during the 2-hour practice. Body mass was significantly less after exercise (POST) and 1 hour after fluid consumption (PFC) when compared with the PRE assessment (PRE = 77.6 6 11.1 kg; POST = 75.7 6 10.9 kg; PFC = 76.4 6 10.9 kg; p , 0.001). All wrestlers reported for testing properly hydrated according to NCAA standards (Usg , 1.020). Urine specific gravity measurements significantly increased above PRE (1.013 6 0.006) at the POST (1.019 6 0.007, p = 0.017) and PFC (1.022 6 0 0.008, p = 0.025) assessments. However, Usg at POST and PFC were not significantly different (p = 0.978). All of the subjects experienced an increase in Usg as a result of the exercise protocol; however, 6 of the 12 subjects would have passed the Usg test at the POST assessment (Usg , 1.020), despite the observed decreases in body mass. Of the 12 subjects, 10 experienced an increase in Usg at the PFC assessment, and all but 1 subject would have failed the Usg test (Usg . 1.020) at the PFC assessment, despite the consumption of 1 L of water. The 2 subjects who did experience a reduction in Usg at PFC lost the least amount of body mass during the exercise protocol (1.3 kg) and were the only subjects who lost ,2% of their PRE body mass (1.8 and 1.5%). Fluid consumption equal to 1 L was ineffective in reducing Usg levels below the NCAA WCP guideline (Usg , 1.020) after exercise-induced fluid loss exceeding 2% of the original body mass. As demonstrated in Table 2, the %BF values at each assessment point (PRE, POST, and PFC) were not significantly different when using SF and ADP methods. Conversely, %BF values were significantly less after exercise for both LBIA and MFBIA. As demonstrated in Table 3, MWW was significantly reduced at both the POST and PFC assessments when using SF and ADP methods. However, MWW was reduced for every subject at the POST assessment and increased at the PFC assessment when using these same methods (SF and ADP). This change in MWW reflected the change in body mass in response to exercise (observed decrease) and fluid consumption (observed increase). Despite similar responses in MWW for SF and ADP, the individual differences in MWW predicted by these 2 NCAA-approved methods ranged from 0.1 to 4.6 kg. When using MFBIA, the MWW was not significantly different between the 3 assessment periods, although MWW was significantly decreased during the POST assessment compared with PRE assessment when using LBIA. A decrease in MWW at the POST assessment was observed among 9 of the 12 subjects when using LBIA; however, the change in
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TABLE 2. Percent body fat (%BF) values presented as mean 6 SD (N = 12).* PRE (%) SF ADP MFBIA LBIA
12.4 13.3 13.3 10.3
6 6 6 6
2.4 3.4 3.4 3.3
POST (%) 12.2 13.5 10.9 8.9
6 6 6 6
2.4 3.6 3.0† 3.4†
PFC (%) 12.3 13.3 11.3 9.5
6 6 6 6
2.5 4.0 3.2† 3.2z
*SF = skinfold; ADP = air displacement plethysmography; LBIA = leg-to-leg bioelectrical impedance analysis; MFBIA = multifrequency bioelectrical impedance analysis; PRE = prepractice; POST = postpractice; PFC = 1 hour after fluid consumption. †Significant difference from the PRE trial (p # 0.05). zSignificant difference compared to both PRE and POST (p # 0.05).
MWW between the assessment periods did not reflect the change in body mass when using bioelectrical impedance (MFBIA and LBIA) as it did when using SF and ADP methods. A comparison of both %BF and MWW measurements determined by the 4 methods of assessment was performed using data from the PRE assessment. Leg-to-leg bioelectrical impedance analysis (10.3 6 3.3%) significantly underestimated %BF when compared with ADP (13.3 6 3.4%; p = 0.050) and MFBIA (13.3 6 3.4%; p = 0.033). For MWW, only LBIA (69.0 6 8.9 kg) was significantly different than MFBIA (66.5 6 8.9 kg; p = 0.031). When using ADP as the criterion, the SEE values for SF, MFBIA, and LBIA during the PRE assessment were 2.07, 3.22, and 2.82 kg, respectively. A summary of results from the survey of NCAA coaches is included in Table 4. The central themes that emerged were as follows: (a) Because of the rule limiting weight loss to
TABLE 3. Minimum wrestling weight (MWW) values presented as mean 6 SD (N = 12).* PRE (kg) SF ADP MFBIA LBIA
67.2 66.6 66.5 69.0
6 6 6 6
8.4 9.1 8.3 9.0
POST (kg) 65.7 64.8 66.8 68.4
6 6 6 6
8.2† 9.0† 8.6 8.8
PFC (kg) 66.3 65.6 67.1 68.6
6 6 6 6
8.0zs 9.3† 8.4 8.8†
*SF = skinfold; ADP = air displacement plethysmography; LBIA = leg-to-leg bioelectrical impedance analysis; MFBIA = multifrequency bioelectrical impedance analysis; PRE = prepractice; POST = postpractice; PFC = 1 hour after fluid consumption. †Significant difference from the PRE trial (p # 0.05). zSignificant difference compared to both PRE and POST (p # 0.05).
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Fluid Consumption and Minimum Wrestling Weight
TABLE 4. NCAA coaches’ survey responses (N = 47).* Question How long have you been coaching at the collegiate level? Please rate your overall satisfaction with the WCP?
If you are dissatisfied in anyway, please explain the circumstances. Please include any suggestions you might have to improve the WCP. Has the WCP ever restricted an athlete from reaching a lower weight class, which you thought was reasonably attainable? Please include suggestions to improve the WCP. Are you aware of any strategies that wrestlers might use to achieve a lower MWW during the WCP?
DI (n = 19)
DII (n = 9)
DIII (n = 19)
0–5 years 1 (5.3%) 2 (22.2%) 7 (36.8%) 6–10 years 7 (36.8%) 1 (11.1%) 6 (31.6%) 11–15 years 3 (15.8%) 1 (11.1%) 2 (10.5%) 16+ years 8 (42.1%) 5 (55.6%) 4 (21.1%) Very satisfied 2 (11.1%) 0 (0.0%) 2 (10.5%) Satisfied 5 (27.8%) 6 (66.7%) 9 (47.4%) Neutral 3 (16.7%) 0 (0.0%) 6 (31.6%) Dissatisfied 8 (44.4%) 1 (11.1%) 2 (10.5%) Very dissatisfied 0 (0.0%) 2 (22.2%) 0 (0.0%) Most common comments (the percentage of those respondents providing a comment to the question is included) 1. The 1.5% plan is unfair (33%) 2. Wrestlers and coaches have devised ways to get around the intent of the WCP (19%) 3. Allow recertification of MWW during the season (14%) Yes, 60% Most common comments in descending order 1. Allow recertification of MWW during the season (39%) No, 40% 2. The 1.5% weight loss plan is unfair (33%) 1. Super hydrate and then workout while holding their urine in an effort to pass the hydration test (49%) 2. Dehydrate to a weight below their desired weight and partially rehydrate in an effort to pass the hydration test (36%) 3. Drinking caffeinated beverages (17%)
*NCAA = National Collegiate Athletic Association; WCP = weight certification program; MWW = minimum wrestling weight.
1.5% body mass per week, wrestlers who wrestle up a weight class do not have ample time to lose weight and return to their original weight class before the next match, and (b) the notion that wrestlers use strategies in an attempt to circumvent the WCP in an effort to establish the lowest allowable MWW.
DISCUSSION Fluid consumption equal to 1 L of water following an exercise-induced fluid loss protocol failed to significantly reduce Usg levels. This finding is in opposition to previous studies that have demonstrated significant reductions in Usg after drinking similar fluid volumes following an overnight fast (7,12). The difference between the present and the aforementioned studies was the behavior that preceded fluid consumption. Previous studies examined fluid consumption after an overnight fast, whereas the present study examined fluid consumption after exercise-induced fluid loss. Exerciseinduced fluid loss significantly reduced body mass (21.9 6 0.48 kg) in the present study, stimulating fluid retention, which resulted in elevated Usg measurements at the PFC assessment. When examined individually, 11 of the 12 subjects would have failed the Usg test (Usg . 1.020) at 1-hour PFC. Furthermore, only 2 of the wrestlers experienced a decrease in Usg after fluid consumption, yet these wrestlers
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lost the least amount of body mass during the exercise session. The reduction in Usg observed among these subjects is not surprising because the fluid volume consumed after exercise more closely matched the fluid-loss experienced during the exercise protocol. Studies have shown that similar fluid volumes (0.6–1 L) have been effective in restoring euhydration (7,12,24); however, acute fluid consumption equal to 1 L of water appears to be ineffective in establishing euhydration among those experiencing exercise-induced fluid loss .2% of the original body mass. We have previously shown that 1 L of water can be used to restore euhydration (Usg , 1.020) while establishing MWWs that were not significantly different than if the assessment were repeated in a hydrated state more than 24 hours after a failed hydration test in accordance with the WCP (7). Rehydration is currently not permitted as part of the WCP; however, these studies support the use of partial rehydration if limited to 1 L immediately following a failed hydration test during the WCP. Because subjects in the present study were unable to reduce Usg through the use of a limited fluid volume, it is unlikely that wrestlers experiencing more severe levels of dehydration would be able to establish euhydration if the fluid volume were restricted to 1 L and the reassessment were offered at 1-hour PFC.
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Journal of Strength and Conditioning Research Currently, SF and ADP are both NCAA-approved methods of assessing %BF during the WCP. Interestingly, mean %BF values determined by these methods were unaffected by exercise and fluid consumption. Conversely, the LBIA and MFBIA technology, which is not approved by the NCAA, demonstrated significant reductions in the %BF values during the POST and PFC assessments compared with the PRE assessment. Previous studies have shown that exercise reduces impedance measured with LBIA and MFBIA, thus lowering %BF estimations (1,10,11). A possible explanation for the decreased impedance may be an increase in muscle perfusion (22) and skin temperature (5), which has been reported after exercise. Another concern related to this technology is that acute fluid consumption increases %BF as a result of increases in body mass and impedance (7,12,13). Whole-body impedance has been shown to increase when fluid is shifted away from the extremities and toward the trunk (12,32,36). It has been postulated that the blood may be redistributed from the periphery to the core in response to fluid entering the stomach and gastrointestinal tract (15), which might explain the increased %BF observed at the PFC assessment. The significant alterations in %BF observed in the present study during the POST and PFC assessments support previous findings related to LBIA and MFBIA (1,7,10–13). The exercise protocol used in the present study resulted in significant reductions in body mass, although %BF values remained unchanged when using both SF and ADP methods. This resulted in MWWs that reflected the change in body mass during the 3 assessment periods and support previous studies identifying body mass as a more important determinant of MWW when compared with %BF (3,7). Although body mass and exercise-induced fluid loss must be controlled during the determination of MWW, it appears that the method of assessment may be as equally important when predicting MWW. An examination of the SEEs revealed that SF- and ADP-predicted MWWs were within approximately 2.0 kg of one another at 68% of the time. Bartok et al. (3) observed a total error of 2.15 kg for MWW when SF was compared with a 4-component body composition assessment criterion (4-C). In a separate study, an evaluation of SF, hydrostatic weighing, and bioelectrical impedance compared with the 4-C method yielded SEEs of 1.72, 1.31, and 2.98 kg, respectively (6). The SF method seems very favorable in comparison to alternate methods, yet we observed differences in MWW determined by SF and ADP methods ranging from 0.09 to 4.61 kg for individual wrestlers. Although both methods are approved by the NCAA, it is important to note that a difference of 4.6 kg could result in a MWW 2 weight classes lower depending on the assessment method used. A 4.6 kg difference was observed in the present study for a 73 kg wrestler. Should a team have access to more than 1 NCAA-approved method, this variability could provide an advantage, albeit a legal one, in which a wrestler may be tested using multiple
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methods and then select the results from the one yielding the lowest MWW. If a 4-kg difference can be observed between 2 approved assessment methods, it is understandable why coaches become frustrated when wrestlers are ineligible for certain weight classes by fractions of a kilogram. When the predicted MWW of the alternate methods was compared with ADP, MFBIA and LBIA exhibited slightly greater error estimates (3.22 kg and 2.82 kg, respectively) than SF (2.07 kg) in the present study. Skinfold measurements have often been shown to have lower SEE values compared with LBIA (6,40) or MFBIA (38) when using hydrostatic weighing or 4-C as the criterion. Similar error estimates (1.51–2.34 kg) have also been reported when LBIA was compared with SF to assess MWW among high school wrestlers (17), suggesting that these methods should not be used interchangeably. Our results are similar to those of Clark et al. (6) where the standard error for bioelectrical impedance was the greatest, and although we failed to observe a significant difference between the mean MWW for LBIA when compared with both SF and ADP methods, the SEEs associated with bioelectrical impedance (LBIA and MFBIA) in addition to its sensitivity to changes in hydration status and fluid shifts have likely resulted in the exclusion of bioelectrical impedance as an NCAA-approved method. The intent of the survey administered to NCAA coaches was to identify the perceptions of coaches toward the WCP and to inquire about possible strategies that may be used in an effort to establish a lower MWW. When asked about their overall satisfaction with the WCP, 53% of the respondents were either “very satisfied” or “satisfied” with the WCP. The most frequently cited concern that coaches identified with the WCP was the rule that limits wrestlers to a weight loss equal to 1.5% of body mass per week. This may pose concerns for the coach because a wrestler who competes and weighs-in near the limit of the next higher weight class would be unable to return to their original weight class the following week because of the 1.5% weight loss limit. Coaches stated that the only way to avoid this issue is to have the individual wrestle up against a heavier opponent while maintaining their normal (lower) weight. The 1.5% weight loss per week is included in the WCP to prevent the rapid, unhealthy weight loss practices common among wrestlers (37). However, any weight loss exceeding 1.5% per week should also be a concern of the coach given its potential adverse relationship on performance. The research surrounding weight loss and performance is inconsistent. Weight loss of approximately 3–5% body mass has been associated with decreased strength and anaerobic performance among wresters (43,44), while other studies have failed to show a change in anaerobic performance when weight loss was equal to 4–6% body mass (14,26). These conflicting results are likely related to the different methodologies used within the studies, but a thorough review conducted by Lambert and Jones (23) addressed the performance deficits associated with weight loss and concluded VOLUME 28 | NUMBER 7 | JULY 2014 |
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Fluid Consumption and Minimum Wrestling Weight that dehydration of 3–4% of body mass impairs muscular endurance and occurs whether the weight loss is rapid or spread out gradually over several days. These data citing performance decrements after weight loss exceeding 3% may lead to the skepticism among coaches questioning the 1.5% rule. However, if athletes are still using rapid weight loss strategies even after the implementation of the WCP as suggested by coaches, a conservative 1.5% will likely remain in an effort to ensure athlete safety and reduce the risk of unhealthy and often dangerous weight-loss procedures. The coaches in the present study identified 3 strategies that may be used by a wrestler to pass the hydration test to establish a lower MWW. The first strategy was reducing one’s weight through exercise and dehydration followed by fluid consumption equal to a volume less than that lost through dehydration, thus allowing the athlete to pass the hydration test and establish a lower MWW. Thirty-six percent of coaches surveyed in the present study indicated that they were aware of a strategy involving exercise-induced dehydration followed by partial rehydration. During this process, wrestlers deliberately dehydrate themselves and consume fluid volumes less than that lost during dehydration to establish a lower MWW. The theory behind this strategy is likely based on the research that has suggested that the rapid consumption of fluid may produce diluted urine samples through a diuretic response and the production of excess urine (35). Similar studies on rehydrating subjects with fluid volumes equal to that lost during dehydration have also shown that Usg may indicate euhydration when, in fact, body mass has not been restored to PRE values (20,33), likely because of excess urine production. Although Usg values have been returned to baseline within 1 hour of consuming water equal to the body mass lost during dehydration (41,42), such a volume load would be counterproductive if the intent were to artificially reduce body mass in the hope of lowering one’s MWW. The present study failed to identify a difference in Usg between the POST and PFC assessments. Therefore, these data do not support the strategy involving exercise-induced fluid loss followed by partial rehydration. It is important to note that the subjects in the present study did not experience the same level of severe dehydration that may be present among wrestlers. Furthermore, fluid consumption was limited to 1 L; therefore, it is possible that more severe levels of dehydration and larger fluid volumes may be used to “trick” the system by establishing acceptable Usg values along with reduced body mass. Future research is warranted in this area. A second strategy identified by coaches was drinking excess fluid or hyperhydrating and then holding urine during exercise-induced fluid loss until the Usg test. The expectation is that the urine will be dilute and not representative of actual hydration status at the time of testing, allowing them to pass the hydration test. The process of hyperhydrating before exercise and holding one’s urine until the hydration assessment is not tested presently. However, 49% of the
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coaches surveyed were aware of this strategy. Although not a purpose of the present investigation, the Usg, %BF, and MWW data at the POST assessment provides preliminary evidence that despite exercise-induced reductions in body mass, Usg values may remain below NCAA WCP standards. As such, if one holds their urine between exercise and the hydration test, it may be possible that the urine remaining in the bladder after exercise is dilute enough to pass the Usg assessment. This finding in the present study where Usg was lower at POST than at PFC assessment supports a potential limitation to Usg as a measure of hydration status because it has been shown to lag behind more time sensitive measures such as plasma osmolality (31,33,41). Although 1 hour has been shown to be adequate time to identify changes in Usg in response to acute fluid consumption (7,12,33,41,42), Usg testing was done immediately after exercise and may not have accurately reflected the subjects’ hydration status at the POST assessment because of urine holding. Again, this is only preliminary and the impact of more extreme dehydration and its effect on “urine holding” as a potential strategy to “trick” the WCP are still undefined and warrant further investigation. The final strategy identified by coaches included the consumption of caffeinated beverages before the hydration test in an attempt to produce diluted urine to pass the hydration test. Although caffeine use was not examined in the present study, the proposition that caffeine may be helpful in allowing one to pass the hydration test more easily may have little merit given that caffeinated beverages have been shown to have no effect on Usg (2,16), yet this has not been studied in direct relationship to the WCP.
PRACTICAL APPLICATIONS To complete body composition testing given the current WCP, the wrestler’s Usg must be ,1.020. The hydration guidelines are useful in preventing dehydration, which may be used to reduce body mass in an attempt to establish a lower MWW. In accordance with the WCP, a wrestler failing the initial hydration assessment must wait a minimum of 24 hours to be retested, placing increased time demands on the personnel responsible for this testing. Acute fluid consumption (approximately 1 L of water) has been previously shown to decrease Usg to an acceptable level (,1.020) among subjects dehydrated (Usg . 1.020) after an overnight fast (7). In the same study, MWW was no different after acute fluid consumption than when the subject waited 24 hours after a failed hydration test as required by the WCP. The use of acute rehydration may offer an alternative during the WCP rather than waiting 24 hours for reassessment; however, it was important to determine if a similar fluid volume could be used to establish euhydration among those experiencing exercise-induced fluid loss, thus “tricking” the system in an effort to establish a lower MWW. In the present study, Usg was not reduced 1 hour after fluid consumption, as it was among those completing an overnight fast; therefore,
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Journal of Strength and Conditioning Research it seems that if water consumption is limited to 1 L after a failed test and Usg is reexamined 1 hour later, euhydration is unlikely among those who have significantly reduced their body mass through exercise-induced fluid loss. Together, these studies suggest that acute fluid consumption limited to 1 L may be effective in reducing Usg and restoring euhydration among those not experiencing exercise-induced fluid loss, although it would be ineffective in restoring euhydration among those who have experienced exercise-induced fluid loss. Given this evidence, acute fluid consumption equal to 1 L may offer an alternative to expedite the WCP after a failed hydration test among those not experiencing exerciseinduced fluid loss when using SF and ADP. Furthermore, athlete safety would not be compromised, as those experiencing deliberate exercise-induced fluid loss would be unable to establish euhydration when using a limited volume of water (1 L). The present study also provides novel insight into the use of deliberate strategies, which may be used by wrestlers in an attempt to circumvent the WCP in an attempt to establish a lower MWW. Although athletes may attempt to use strategies such as fluid consumption after exercise or urine holding, it is important to note that none of the strategies mentioned here have been proven to be effective in establishing lower MWWs. Furthermore, any attempt at using exercise-induced fluid loss strategies uses an inherent danger and should be avoided. Additional researches examining the various strategies that may be used by wrestlers in an effort to “trick” the system are warranted in an effort to maintain the safety of the athlete during the WCP.
ACKNOWLEDGMENTS
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6. Clark, RR, Bartok, C, Sullivan, JC, and Schoeller, DA. Minimum weight prediction methods cross-validated by the four-component model. Med Sci Sports Exerc 36: 639–647, 2004. 7. Cutrufello, PT and Dixon, CB. The effect of acute fluid consumption and hydration status on percent body fat and minimum wrestling weight. J Strength Cond Res 27: 1950–1957, 2013. 8. Davis, SE, Dwyer, GB, Reed, K, Bopp, C, Stosic, J, and Shepanski, M. Preliminary investigation: The impact of the NCAA wrestling weight certification program on weight cutting. J Strength Cond Res 16: 305–307, 2002. 9. Dempster, P and Aitkens, S. A new air displacement method for the determination of human body composition. Med Sci Sports Exerc 27: 1692–1697, 1995. 10. Demura, S, Yamaji, S, Goshi, F, and Nagasawa, Y. The influence of transient change of total body water on relative body fats based on three bioelectrical impedance analyses methods. Comparison between before and after exercise with sweat loss, and after drinking. J Sports Med Phys Fitness 42: 38–44, 2002. 11. Dixon, CB and Andreacci, JL. Effect of resistance exercise on percent body fat using leg-to-leg and segmental bioelectrical impedance analysis in adults. J Strength Cond Res 23: 2025–2032, 2009. 12. Dixon, CB, LoVallo, SJ, Andreacci, JL, and Goss, FL. The effect of acute fluid consumption on measures of impedance and percent body fat using leg-to-leg bioelectrical impedance analysis. Eur J Clin Nutr 60: 142–146, 2006. 13. Dixon, CB, Ramos, L, Fitzgerald, E, Reppert, D, and Andreacci, JL. The effect of acute fluid consumption on measures of impedance and percent body fat estimated using segmental bioelectrical impedance analysis. Eur J Clin Nutr 63: 1115–1122, 2009. 14. Fogelholm, GM, Koskinen, R, Laakso, J, Rankinen, T, and Ruokonen, I. Gradual and rapid weight loss: Effects on nutrition and performance in male athletes. Med Sci Sports Exerc 25: 371–377, 1993. 15. Gomez, T, Mole, PA, and Colins, A. Dilution of body fluid electrolytes affects bioelectrical impedance measurements. Sports Med Train Rehabil 4: 291–298, 1993.
The authors express their gratitude to Emily Mossler and Stephen Gadomski for their assistance during the data collection process. This study was funded through an internal research grant from The University of Scranton. The authors have no conflict of interest to declare. The results of this study do not constitute the endorsement of any product by the authors or the National Strength and Conditioning Association.
16. Grandjean, AC, Reimers, KJ, Bannick, KE, and Haven, MC. The effect of caffeinated, non-caffeinated, caloric and non-caloric beverages on hydration. J Am Coll Nutr 19: 591–600, 2000.
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