European Journal of
Applied
Eur. J. Appl. Physiol. 39, 277-282 (1978)
Physiology and Occupational Physiology c~ Springer-Verlag 1978
Maximal Oxygen Intake and Body Composition of Female Dancers L. P. Novak, L. A. Magill, and J. E. Schutte Department of Anthropology, Southern Methodist University, Dallas, TX 75275, U.S.A.
Summary. Complete paucity of any data regarding the influence of habitual dance on cardiovascular-pulmonary fitness and body composition of female dancers prompted this study in which 12 female dancers and 12 sedentary female students of the same age range participated as subjects. Maximal oxygen intake was determined on the treadmill, body composition was calculated from skinfolds and vital signs were determined besides measurements of height and weight. Dancers had significantly lower weight, lower resting heart rate, and lower diastolic blood pressure. Systolic blood pressure was also lower in dancers but the difference between the means did not reach statistical significance. Maximal oxygen intake was higher in dancers when expressed in relative terms. Dancers had also significantly lower total body fat. In conclusion, it seems that, dance with all the variations, should be encouraged in schools as a suitable behavioral modifier of sedentary habits and for maintenance of physical fitness and ideal weight. Key words: Dance -- Physical fitness - Body composition - Maximal oxygen intake. Lack of cardiovascular-pulmonary fitness and obesity are two risk factors associated with cardiovascular disease. Physical inactivity leading to positive caloric balance is becoming the way of life in the USA and other industrialized nations. While physiologists were studying various athletes in order to determine their maximal aerobic capacity and their leanness, the rest of the population escaped the eager minds of scientists always looking for the extremes. And yet, it is the majority of the population engulfed by industrialization and immobilized physically, which requires immediate attention in the view of increasing evidence which seems to link cardiovascular disease with habitual inactivity, lack of cardiovascular-respiratory fitness and obesity. Offprint request to: Professor L. P. Novak, Ph.D. (address see above)
0301-5548/78/0039/0277/$ 01.20
278
L.P. Novak et al.
The benefits of various physical activities on the cardiovascular and pulmonary systems are very well known. Energy expenditure during physical activities enhances caloric balance or even weight loss. Thus, various types of exercises with various caloric expenditures can be utilized for counselling those individuals with low cardiovascular fitness and weight problems. Dance, in general, is progressively becoming very popular in schools and is included in the program of recreational facilities and various private clubs. Schoolchildren as well as adults are participating in greater numbers in dance classes either for enjoying body movements performed according to classical, modern, or jazz music or simply, they seek improvement of the posture, loss of weight, or improvement of physical as well as cardiovascular-pulmonary fitness. There is a complete paucity of any data regarding influence of chronic dance on cardiovascular-pulmonary fitness and body composition of female dancers. Therefore, this study was designed to provide the first information about maximal aerobic capacity and body composition of college female dancers and to contrast their results with those of sedentary female college students.
Subjects and Methods The subjects for this study were undergraduate and graduate female dancers ranging from 19-29 years of age. They had been participating in dance programs between 6-7 years and between 10-15 h per week on an average. The control group were undergraduate and graduate female students of the same age range who were not involved in any regular physical activities. All subjects were healthy and in good nutritional status. Each subject had to go through the followingprocedures: a) vital signs determinations,b) anthropometrical measurements, c) calculations of body fat and lean body mass, and d) maximal oxygen determination. All subjects were dressed in two-piece swimming suits. After 10-15 rain sitting and resting, heart rate, breathing rate and blood pressure was determined. Then, body weight was recorded in kg within 20 g, accuracy on a beam type weighing scale. Standing height was measured to 1 mm accuracy with a sliding anthropometer attached to the wall. Subcutaneous skinfolds were measured by Lange Skinfold Calipers with a built-in spring exerting a constant pressure of 10 g/mm2 between the jaws. Dorsal upper-arm, subscapular, iliac crest, thigh, and calf skinfoldswere measured to provide evidence about leanness-fatnessof the subjects. The Sloan formula (1962) for prediction of body density in females was used and total body fat was calculated from body density according to the proposal of Bro~ek (1963). The maximal oxygen intake was determinedon the treadmill according to the method proposed by Taylor et al. (1963). Before the actual test, a warm-up walk for 3 min at 3 mph was performed by each subject during which the heart rate was monitored by continuous ECG. The actual test for determination of maximal oxygen intake started at 70% of the predicted maximal aerobic power. Work-load was increased each minute by 2.5% until near exhaustion was reached. At that time, expired air was collected into the Tissot gasometer for 30 s. Concentration of oxygen and carbon dioxidein the expired air was analyzed with Beckman Model OM-11 and Beckman Model LB-2 analyzers.
Results The informations about vital signs of all the subjects are in Table 1. The dancers were significantly younger and had significantly lower weight compared to the control group. In addition, they also had significantly lower resting heart rate as well as
279
Oxygen Intake and Body Composition of Dancers Table 1. Age, heights, weights, and vital signs. Means and standard deviations Group
Dancers
N
Age (years)
12
Controls 12
Height (cm)
Weight (kg)
Heart rate (beats/ min)
Respiratory rate (breaths/ min)
Blood pressure systolic diastolic (mm Hg) (ram Hg)
21.2+1.6" 162.7+7.9
51.2+4.6 a
6 5 + 13a
16+3
101_+8
23.6_+2.4
55.3+4.5
7 8 + 13
15+3
110_+ 14 6 7 + 9
167.0_+5.4
61_+8 a
Significant at 0.05 level
Table 2. Maximal oxygen consumption. Means and standard deviations Group
N
Maximum oxygen consumption (1)
Maximum heart rate (beats/ (ml/kg/min) min)
Grade (%)
Speed (mph)
Time (min)
Dancers
12
2.1 + 0.3
41.5 _+ 6.7 a
185 _+ 7
7.7 _+ 2.0a
5.7 _+ 0.4"
3.5 + 0.5
Controls
12
2.0 +_0.4
36.8 + 5.5
191 + 9
4.8 _+ 1.0
5.3 + 0.5
3.0 _+ 0.5
" Significant at 0.05 level
Table 3. Total body fat and lean body mass. Means and standard deviations Group
N
Total body fat (kg)
Lean body mass (%)
(kg)
(%)
Dancers
12
10.6 + 2.9 a
20.5 + 4.6 a
40.7 _+ 3.5
79.5 _+ &5 a
Controls
12
14.9 _+ 2.6
26.5 _+ 3.6
40.5 + 3.1
73.5 • 3.6
a Significant at 0.05 level
the diastolic blood pressure. Even though the systolic blood pressure was found to be lower as well, the difference between the dancers and the control group did not reach statistical significance. The means and standard deviations for maximal oxygen intake, maximal heart rate and treadmill data are presented in Table 2. Absolute values of maximal oxygen intake were almost the same for both group of subjects. However, per kg of body weight, maximal oxygen of dancers was significantly higher by more than 5 ml/kg/min. This higher oxygen intake was reached at a lower maximal heart rate, at significantly higher grade elevation, at a greater speed of the treadmill and it took about 30 s longer to reach it. Table 3 presents the means and standard deviations of body composition analyses. The dancers had significantly lower amounts of body fat both in absolute and
280
L.P. Novak et al.
Table 4. Subcutaneous skinfolds. Means and standard deviations. Skinfold, mrn Group
Dancers Controls a
N
12 12
Upper arm dorsal (mm)
Sub. scapular (mm)
Iliac crest (ram)
Thigh
Calf
(mm)
(turn)
12.2 _+ 4.0a 16.6 + 4.6
10.3 __. 3.9 11.3 + 4.6
17.8 ___8.4a 29.1 + 5.2
17.3 5.6a 24.0 + 8.6
12.9 _+ 5.4a 17.0 _+ 6.9
___
Significant at 0.05 level
relative terms. On the other hand, lean body mass of both groups was practically the same. Only when lean body mass was expressed in percentage of body weight, significant difference was found in favor of the dancers. Table 4 shows the means and standard deviations of all subcutaneous skinfolds. The dancers exhibited significantly lower fat-folds on all sites sampled except that measured under the scapula.
Discussion The maximal oxygen intake of dancers has received little attention in the past years. Yet, dancers are subjected daily to vigorous training of several hours which stresses cardiovascular-pulmonary system. Large muscle groups are involved in various movements with varying speeds. The work-load could be quantified from moderate to heavy based on investigation of Seliger (1970) in Czechoslovakia. The author inferred that ballet dancers have to withstand considerable physical loads of endurance character. The results of this studYocompare well with those of Metheny et al. (1942), Macnab et al. (1968), Katch et al. (1973), who reported maximal oxygen intakes of normal females of similar ages to be 40.9, 39.1, and 35.4 ml/kg/min, respectively. Hermansen and Anderson (1965) provided a range for sedentary and trained college females to be between 30.0-55.0 ml/kg/min. These investigators reported that sedentary women achieve maximal oxygen intake of about 30.0 ml/kg/min while active and highly trained college female athletes reached 37.0-39.0 ml/kg/min and 46.0-55.0 ml/kg/min, respectively. And as the aerobic requirements increase with specific endurance events, higher maximal oxygen intakes have been recorded as it was documented by Plowman (1974) in a study of female athletes and by Novak (1972). However, the quest for the highest maximal oxygen intake in selected few individuals specializing in one or two athletic events for a limited period of time out of total life span of human species, can hardly induce enthusiasm in a normal population participation in recreational physical activities. And thus, in a search for suitable exercise to induce certain degree of cardiovascular-pulmonary fitness and energy expenditure, dance emerged as a qualifying candidate fo fulfill adequately these requirements. If the number of adults who do not engage themselves in any physical
Oxygen Intake and Body Composition of Dancers
281
activity is about 45% of the total number of adults in the U S A (1973), then, dance could well reduce this high percentage to a lower level. A n average physical fitness is desirable in general population because evidence is accumulating, which suggests, that habitual physical activity m a y protect against the cardiovascular disease processes by collateral supply of the coronary artery, by increasing the size of coronary arteries, by increasing cardiac efficiency, by lowering triglycerides, blood pressure and by decreasing coagulability of blood as well as maintenance of ideal weight (1970). If, then, the results of this limited study are indicative of the nature of physical and physiological work-load which dance is placing upon cardiovascular-pulmonary systems, the achieved maximal oxygen intake of dancers 41.5 ml/kg/min compares well with Astrand's (1952) norms of physical fitness. Astrand's classification of fitness levels of females between 2 0 - 2 9 years old is subdivided into five chtegories. Low physical fitness is achieved by those females whose maximal oxygen intake is 28.0 ml/kg/min or lower, while 2 9 . 0 - 3 4 . 0 ml/kg/min denotes fair physical fitness and an average is achieved by maximal oxygen intake between 3 5 . 0 - 4 3 . 0 ml/kg/min. Thus, the dancers in this study maintained their physical fitness at the higher spectrum of the average category while the sedentary students serving as controls for this study achieved the lower spectrum of the average category. Therefore, it seems that dance with all the variations should be encouraged in the schools as a suitable modifier for the maintenance of physical fitness and ideal weight and as a behavioral modifier of sedentary habits.
References
Astrand, P. O.: Experimental studies of physical working capacity in relation to sex and age. Copenhagen: Munksgaard 1952 Bro~ek, J., Grande, F., Anderson, J. T., Keys, A.: Densitometric analysis of body composition: revision of some quantitative assumptions. Ann. N.Y. Acad. Sci. 110, 113-140 (1963) Hermansen, L., Anderson, K. L.: Aerobic work capacity in young Norwegian men and women. J. Appl. Physiol. 20, 425-431 (1965) Katch, F. I., McArdle, W. K., Czula, R., Pechar, G. S.: Maximal oxygen intake, endurance running performance, and body composition in college women. Res. Q. Am. Assoc. Health Phys. Educ. 44, 301-312 (1973) Macnab, R. B. J., Conger, P. R., Taylor, P. S., Neil, S. E.: Maximal oxygen uptake, physical work capacity and body composition of males and females. Congress, Internat. Committee Stand. Phys. Fitness Tests, Mexico City 1968 Metheny, E., Brouha, L., Johnson, R. E., Forbes, W. A.: Some physiologic responses of men and women to moderate and strenuous exercise: a comparative study. Am. J. Physiol. 137, 318-326 (1942) National Adult Physical Fitness Survey, Newsletter President's Council on Physical Fitness and Sports 14 May, 1973 Novak, L. P.: Maximal oxygen consumption, pulmonary function, body composition, and anthropometry of adolescent female athletes. Int. Z. Angew. Physiol. 31, 103-119 (1973) Plowman, Sharon: Physiological characteristics of female athletes. Res. Q. Am. Assoc. Health Phys. Educ. 45, 349--362 (1974) Seliger, V., Glucksmann, J., Pachlopnik, J., Pachlonikova, I.: Evaluation of stage artists' activities on basis of telemetrical measurements of heart rates. Int. Z. Angew. Physiol. 28, 86--104 (1970)
282
L.P. Novak et al.
Siegel, W., Blomquist, G., Mitchell, J. H.: Effects of quantitated physical training program on middleaged sedentary man. Circulation 41, 19-39 (1970) Sloan, A. W., Burt, L J., Blyth, C. S.: Estimation of body fat in young women. J. Appl. Physiol. 17, 967-970 (1962) Taylor, H. L., Wang, W., Rowell, L., Blomquist, G.: The standardization and interpretation of submaximal and maximal tests of working capacity. Pediatrics 411 (Suppl. 32), 703-720 (1963) Accepted June 30, 1978
Applied
Eur. J. Appl. Physiol. 39, 277-282 (1978)
Physiology and Occupational Physiology c~ Springer-Verlag 1978
Maximal Oxygen Intake and Body Composition of Female Dancers L. P. Novak, L. A. Magill, and J. E. Schutte Department of Anthropology, Southern Methodist University, Dallas, TX 75275, U.S.A.
Summary. Complete paucity of any data regarding the influence of habitual dance on cardiovascular-pulmonary fitness and body composition of female dancers prompted this study in which 12 female dancers and 12 sedentary female students of the same age range participated as subjects. Maximal oxygen intake was determined on the treadmill, body composition was calculated from skinfolds and vital signs were determined besides measurements of height and weight. Dancers had significantly lower weight, lower resting heart rate, and lower diastolic blood pressure. Systolic blood pressure was also lower in dancers but the difference between the means did not reach statistical significance. Maximal oxygen intake was higher in dancers when expressed in relative terms. Dancers had also significantly lower total body fat. In conclusion, it seems that, dance with all the variations, should be encouraged in schools as a suitable behavioral modifier of sedentary habits and for maintenance of physical fitness and ideal weight. Key words: Dance -- Physical fitness - Body composition - Maximal oxygen intake. Lack of cardiovascular-pulmonary fitness and obesity are two risk factors associated with cardiovascular disease. Physical inactivity leading to positive caloric balance is becoming the way of life in the USA and other industrialized nations. While physiologists were studying various athletes in order to determine their maximal aerobic capacity and their leanness, the rest of the population escaped the eager minds of scientists always looking for the extremes. And yet, it is the majority of the population engulfed by industrialization and immobilized physically, which requires immediate attention in the view of increasing evidence which seems to link cardiovascular disease with habitual inactivity, lack of cardiovascular-respiratory fitness and obesity. Offprint request to: Professor L. P. Novak, Ph.D. (address see above)
0301-5548/78/0039/0277/$ 01.20
278
L.P. Novak et al.
The benefits of various physical activities on the cardiovascular and pulmonary systems are very well known. Energy expenditure during physical activities enhances caloric balance or even weight loss. Thus, various types of exercises with various caloric expenditures can be utilized for counselling those individuals with low cardiovascular fitness and weight problems. Dance, in general, is progressively becoming very popular in schools and is included in the program of recreational facilities and various private clubs. Schoolchildren as well as adults are participating in greater numbers in dance classes either for enjoying body movements performed according to classical, modern, or jazz music or simply, they seek improvement of the posture, loss of weight, or improvement of physical as well as cardiovascular-pulmonary fitness. There is a complete paucity of any data regarding influence of chronic dance on cardiovascular-pulmonary fitness and body composition of female dancers. Therefore, this study was designed to provide the first information about maximal aerobic capacity and body composition of college female dancers and to contrast their results with those of sedentary female college students.
Subjects and Methods The subjects for this study were undergraduate and graduate female dancers ranging from 19-29 years of age. They had been participating in dance programs between 6-7 years and between 10-15 h per week on an average. The control group were undergraduate and graduate female students of the same age range who were not involved in any regular physical activities. All subjects were healthy and in good nutritional status. Each subject had to go through the followingprocedures: a) vital signs determinations,b) anthropometrical measurements, c) calculations of body fat and lean body mass, and d) maximal oxygen determination. All subjects were dressed in two-piece swimming suits. After 10-15 rain sitting and resting, heart rate, breathing rate and blood pressure was determined. Then, body weight was recorded in kg within 20 g, accuracy on a beam type weighing scale. Standing height was measured to 1 mm accuracy with a sliding anthropometer attached to the wall. Subcutaneous skinfolds were measured by Lange Skinfold Calipers with a built-in spring exerting a constant pressure of 10 g/mm2 between the jaws. Dorsal upper-arm, subscapular, iliac crest, thigh, and calf skinfoldswere measured to provide evidence about leanness-fatnessof the subjects. The Sloan formula (1962) for prediction of body density in females was used and total body fat was calculated from body density according to the proposal of Bro~ek (1963). The maximal oxygen intake was determinedon the treadmill according to the method proposed by Taylor et al. (1963). Before the actual test, a warm-up walk for 3 min at 3 mph was performed by each subject during which the heart rate was monitored by continuous ECG. The actual test for determination of maximal oxygen intake started at 70% of the predicted maximal aerobic power. Work-load was increased each minute by 2.5% until near exhaustion was reached. At that time, expired air was collected into the Tissot gasometer for 30 s. Concentration of oxygen and carbon dioxidein the expired air was analyzed with Beckman Model OM-11 and Beckman Model LB-2 analyzers.
Results The informations about vital signs of all the subjects are in Table 1. The dancers were significantly younger and had significantly lower weight compared to the control group. In addition, they also had significantly lower resting heart rate as well as
279
Oxygen Intake and Body Composition of Dancers Table 1. Age, heights, weights, and vital signs. Means and standard deviations Group
Dancers
N
Age (years)
12
Controls 12
Height (cm)
Weight (kg)
Heart rate (beats/ min)
Respiratory rate (breaths/ min)
Blood pressure systolic diastolic (mm Hg) (ram Hg)
21.2+1.6" 162.7+7.9
51.2+4.6 a
6 5 + 13a
16+3
101_+8
23.6_+2.4
55.3+4.5
7 8 + 13
15+3
110_+ 14 6 7 + 9
167.0_+5.4
61_+8 a
Significant at 0.05 level
Table 2. Maximal oxygen consumption. Means and standard deviations Group
N
Maximum oxygen consumption (1)
Maximum heart rate (beats/ (ml/kg/min) min)
Grade (%)
Speed (mph)
Time (min)
Dancers
12
2.1 + 0.3
41.5 _+ 6.7 a
185 _+ 7
7.7 _+ 2.0a
5.7 _+ 0.4"
3.5 + 0.5
Controls
12
2.0 +_0.4
36.8 + 5.5
191 + 9
4.8 _+ 1.0
5.3 + 0.5
3.0 _+ 0.5
" Significant at 0.05 level
Table 3. Total body fat and lean body mass. Means and standard deviations Group
N
Total body fat (kg)
Lean body mass (%)
(kg)
(%)
Dancers
12
10.6 + 2.9 a
20.5 + 4.6 a
40.7 _+ 3.5
79.5 _+ &5 a
Controls
12
14.9 _+ 2.6
26.5 _+ 3.6
40.5 + 3.1
73.5 • 3.6
a Significant at 0.05 level
the diastolic blood pressure. Even though the systolic blood pressure was found to be lower as well, the difference between the dancers and the control group did not reach statistical significance. The means and standard deviations for maximal oxygen intake, maximal heart rate and treadmill data are presented in Table 2. Absolute values of maximal oxygen intake were almost the same for both group of subjects. However, per kg of body weight, maximal oxygen of dancers was significantly higher by more than 5 ml/kg/min. This higher oxygen intake was reached at a lower maximal heart rate, at significantly higher grade elevation, at a greater speed of the treadmill and it took about 30 s longer to reach it. Table 3 presents the means and standard deviations of body composition analyses. The dancers had significantly lower amounts of body fat both in absolute and
280
L.P. Novak et al.
Table 4. Subcutaneous skinfolds. Means and standard deviations. Skinfold, mrn Group
Dancers Controls a
N
12 12
Upper arm dorsal (mm)
Sub. scapular (mm)
Iliac crest (ram)
Thigh
Calf
(mm)
(turn)
12.2 _+ 4.0a 16.6 + 4.6
10.3 __. 3.9 11.3 + 4.6
17.8 ___8.4a 29.1 + 5.2
17.3 5.6a 24.0 + 8.6
12.9 _+ 5.4a 17.0 _+ 6.9
___
Significant at 0.05 level
relative terms. On the other hand, lean body mass of both groups was practically the same. Only when lean body mass was expressed in percentage of body weight, significant difference was found in favor of the dancers. Table 4 shows the means and standard deviations of all subcutaneous skinfolds. The dancers exhibited significantly lower fat-folds on all sites sampled except that measured under the scapula.
Discussion The maximal oxygen intake of dancers has received little attention in the past years. Yet, dancers are subjected daily to vigorous training of several hours which stresses cardiovascular-pulmonary system. Large muscle groups are involved in various movements with varying speeds. The work-load could be quantified from moderate to heavy based on investigation of Seliger (1970) in Czechoslovakia. The author inferred that ballet dancers have to withstand considerable physical loads of endurance character. The results of this studYocompare well with those of Metheny et al. (1942), Macnab et al. (1968), Katch et al. (1973), who reported maximal oxygen intakes of normal females of similar ages to be 40.9, 39.1, and 35.4 ml/kg/min, respectively. Hermansen and Anderson (1965) provided a range for sedentary and trained college females to be between 30.0-55.0 ml/kg/min. These investigators reported that sedentary women achieve maximal oxygen intake of about 30.0 ml/kg/min while active and highly trained college female athletes reached 37.0-39.0 ml/kg/min and 46.0-55.0 ml/kg/min, respectively. And as the aerobic requirements increase with specific endurance events, higher maximal oxygen intakes have been recorded as it was documented by Plowman (1974) in a study of female athletes and by Novak (1972). However, the quest for the highest maximal oxygen intake in selected few individuals specializing in one or two athletic events for a limited period of time out of total life span of human species, can hardly induce enthusiasm in a normal population participation in recreational physical activities. And thus, in a search for suitable exercise to induce certain degree of cardiovascular-pulmonary fitness and energy expenditure, dance emerged as a qualifying candidate fo fulfill adequately these requirements. If the number of adults who do not engage themselves in any physical
Oxygen Intake and Body Composition of Dancers
281
activity is about 45% of the total number of adults in the U S A (1973), then, dance could well reduce this high percentage to a lower level. A n average physical fitness is desirable in general population because evidence is accumulating, which suggests, that habitual physical activity m a y protect against the cardiovascular disease processes by collateral supply of the coronary artery, by increasing the size of coronary arteries, by increasing cardiac efficiency, by lowering triglycerides, blood pressure and by decreasing coagulability of blood as well as maintenance of ideal weight (1970). If, then, the results of this limited study are indicative of the nature of physical and physiological work-load which dance is placing upon cardiovascular-pulmonary systems, the achieved maximal oxygen intake of dancers 41.5 ml/kg/min compares well with Astrand's (1952) norms of physical fitness. Astrand's classification of fitness levels of females between 2 0 - 2 9 years old is subdivided into five chtegories. Low physical fitness is achieved by those females whose maximal oxygen intake is 28.0 ml/kg/min or lower, while 2 9 . 0 - 3 4 . 0 ml/kg/min denotes fair physical fitness and an average is achieved by maximal oxygen intake between 3 5 . 0 - 4 3 . 0 ml/kg/min. Thus, the dancers in this study maintained their physical fitness at the higher spectrum of the average category while the sedentary students serving as controls for this study achieved the lower spectrum of the average category. Therefore, it seems that dance with all the variations should be encouraged in the schools as a suitable modifier for the maintenance of physical fitness and ideal weight and as a behavioral modifier of sedentary habits.
References
Astrand, P. O.: Experimental studies of physical working capacity in relation to sex and age. Copenhagen: Munksgaard 1952 Bro~ek, J., Grande, F., Anderson, J. T., Keys, A.: Densitometric analysis of body composition: revision of some quantitative assumptions. Ann. N.Y. Acad. Sci. 110, 113-140 (1963) Hermansen, L., Anderson, K. L.: Aerobic work capacity in young Norwegian men and women. J. Appl. Physiol. 20, 425-431 (1965) Katch, F. I., McArdle, W. K., Czula, R., Pechar, G. S.: Maximal oxygen intake, endurance running performance, and body composition in college women. Res. Q. Am. Assoc. Health Phys. Educ. 44, 301-312 (1973) Macnab, R. B. J., Conger, P. R., Taylor, P. S., Neil, S. E.: Maximal oxygen uptake, physical work capacity and body composition of males and females. Congress, Internat. Committee Stand. Phys. Fitness Tests, Mexico City 1968 Metheny, E., Brouha, L., Johnson, R. E., Forbes, W. A.: Some physiologic responses of men and women to moderate and strenuous exercise: a comparative study. Am. J. Physiol. 137, 318-326 (1942) National Adult Physical Fitness Survey, Newsletter President's Council on Physical Fitness and Sports 14 May, 1973 Novak, L. P.: Maximal oxygen consumption, pulmonary function, body composition, and anthropometry of adolescent female athletes. Int. Z. Angew. Physiol. 31, 103-119 (1973) Plowman, Sharon: Physiological characteristics of female athletes. Res. Q. Am. Assoc. Health Phys. Educ. 45, 349--362 (1974) Seliger, V., Glucksmann, J., Pachlopnik, J., Pachlonikova, I.: Evaluation of stage artists' activities on basis of telemetrical measurements of heart rates. Int. Z. Angew. Physiol. 28, 86--104 (1970)
282
L.P. Novak et al.
Siegel, W., Blomquist, G., Mitchell, J. H.: Effects of quantitated physical training program on middleaged sedentary man. Circulation 41, 19-39 (1970) Sloan, A. W., Burt, L J., Blyth, C. S.: Estimation of body fat in young women. J. Appl. Physiol. 17, 967-970 (1962) Taylor, H. L., Wang, W., Rowell, L., Blomquist, G.: The standardization and interpretation of submaximal and maximal tests of working capacity. Pediatrics 411 (Suppl. 32), 703-720 (1963) Accepted June 30, 1978
