Maximal Anaerobic Power: Relationship to Anthropometric Characteristics during Growth B. Mercier, J. Mercier, P. Granier, D. Le Gallais, Ch. Préfaut Service d'Exploration de la Fonction Respiratoire, Hôpital Aiguelongue, Montpellier, 34059 cedex, France
16, 27, 28, 29), which is performed against only one standard braking force. As Vandewalle et al. (34) have shown, this test
B. IViercier, J. Mercier, P. Granier, D. Le Gal-
lais and Ch. Préfaut, Maximal Anaerobic Power: Relationship to Anthropometric Characteristics during Growth. mt JSportsMed, Vol l3,No l,pp2l —26,1992. Accepted after revision: June 3, 1991.
The purpose of this study was to determine the effects of age in relation to anthropometric characteristics upon maximal anaerobic power of legs in sixtynine young boys aged 11 to 19 years. Maximal anaerobic power (Wmax) was measured by the force-velocity test.
does not measure maximal anaerobic power if the braking force is not optimal. Therefore, in order to study the effect of age upon maximal anaerobic power of legs with accuracy, it is advisable to use a test with incremental braking forces such as the force-velocity test. To our knowledge no studies have been carried out using the force-velocity test with leg during growth period. Recently, Vandewalle Ct al. (35) have measured arm maximal anaerobic power in young swimmers aged 12—18 years. These subjects were trained, however, and the respective roles of growth and training are difficult to differentiate. While there are some data on the relationship between anaerobic performance of legs and the various estimates of lean tissue (2, 5, 6, 16, 27, 29), there is no published information on the re-
Lean body mass (LBM) was determined from all four skin-
lationship between leg maximal anaerobic power measured
fold thickness measurements, leg volume (LV) was estimated by anthropometric method, and anthropometric measurements were used to determine total muscular mass
with the force-velocity test and lean body mass, leg volume, or total muscle mass in children. The purpose of this study, therefore, was to determine the effects of age in relation to anthro-
(TMM). Wmax increased significantly
(F 44.1,
pometric characteristics upon maximal anaerobic power of
p < 0.001) between 11 and 19 years and was correlated with LV (r = 0.84) and TMM (r = 0.88). It was most highly correlated with LBM (r = 0.94), which best explained the percentage of the total variance of Wmax (88%). Normalized Wmax (Wmax/LBM) also increased significantly be-
the legs measured by the force-velocity test during the growth period in sedentary children and adolescents.
tween 11 and 19 years (F = 21.9, p < 0.001). In conclusion, Wmax determined by the force-velocity test was closely re-
lated to anthropometric characteristics, especially LBM, during the growth period. Furthermore, even when corrected for lean body mass, maximal anaerobic power was always found to increase. This suggests that other undetermined factors, in addition to the amount of lean tissue mass, may explain the increase of Wmax during the force-velocity test. Key words
Growth, force-velocity test, maximal anaerobic power, anthropometric characteristics
Methods
Subjects Sixty-nine young boys, aged from 11 to 19 years, volunteered to participate in the present study. Written consent was obtained from the parents, as well as the approval from the National Ethical Committee. The boys had been informed of the procedures and purposes of the study. The tests were conducted during school hours in a special testing area set up at the school. All subjects included in the study underwent a complete clinical and electrocardiological examination. They participated only in the school physical education programs (3 hours a week). Subjects were classed into 7 homo-
geneous age groups; the range in the groups from 11 to 15 months. In the groups from 16 to 19 years, years was 1 year it was 2 years (Table 1).
Anthropometric characteristics Introduction
There have been numerous studies on the anaerobic power of legs in children and adolescents (2, 5, 6, 16, 23, 24, 25, 27, 28, 29). Most of them used the Wingate test (2, __________________________________________________ lnt.J.SportsMed.13(1992)21—26 GeorgThieme Verlag StuttgartNew York
Body weight (BW), standing height (Ht), and sitting height (SHt) were measured; extended upper-arm circumference, upper-thigh circumference, maximum calf cir. . . . cumference and bicipital, tricipital, subscapular, and suprailiac skinfold thicknesses were measured on the left side of the body. All measurements were taken by the same observer in the positions and following the techniques established by the International Biological Programme (36). Body density was
Downloaded by: University of British Columbia. Copyrighted material.
Abstract
mt. J. Sports Med. 13(1992)
B. Mercier, J. Mercier, P. Granier, D. Le Gallais, Ch. Prefaut
Table 1 Age groups and mean values (±sem) of anthropometric characteristics n
Ht
LL
BW
LBM
LV
TMM
)yrs)
(cm)
(cm)
(kg)
(kg)
(I)
(kg)
11
144.7 2.3
69.6 2
35.9
32.1
7.6 0.4
13.9 0.7
147.3
71.4 0.9
39.3
34.5
8.4
15.6
1.7
1.1
0.5
1.1
78.8 0.8
44.4
39.9
16.1
1.1
1
9.5 0.3
79.9
49.4
10.6
0.8
1.7
44 1.4
20.9 0.9
Age
groups 10
12
10
1.9 13
10
157.8
1.7 14
9
159
1.6 15
10
10
10
16.17
18.19
1.3
1
0.4
165.4 2.1
82
55.4
49.2
11.8
1
1.8
1.5
0.3
176.8
87.6 1.4
66.6 3.4
59.8 2.6
14
2.6 176.7
86.9 0.7
65.1 2.1
58.1
13.6
1.8
1.4
0.9
0.6
0.5
22.9 1.2 28 1.7 27.4 1.4
n = number of subjects, height (Ht), leg length (LL), body weight (BM), lean body mass {LBM), leg volume (LV), total muscular mass (1MM).
same exercise against a braking force increased by 1 kg. The first two exercises, done at low braking forces, were considered as a warm-up and familiarization with the test. We assumed that the subject attained the braking force corresponding to his maximal power if an additional amount of load in-
duced a power decrease. As previously described (22),
an
automatic system was used to determine the maximal velocity for each braking force and to calculate the force-velocity relations. As pointed out by Vandewalle et al. (31), the relation between braking force F and velocity V can be expressed as fol-
lows: V=b—aF or V=Vo—VIF/Fo=Vo(l—F/Fo) where Vo is the intercept with the velocity axis, i. e., maximal velocity
for braking force equal to zero, and Fo the intercept with the force axis, i. e., maximal braking force corresponding to velocity equal to zero. These were calculated by extrapolation of the linear relation linking the braking force and the velocity at a pedalling frequency greater than 90 rpm. This automatic system permitted us to verify that the maximal velocity for each braking force was achieved even for the youngest boys within
the 6 s. Given the linear force-velocity relationships, the power-velocity and ower-force relationship are parabolic. The maximal power ( max) was defined as the highest power value calculated for the different braking forces.
Statistics
All values reported are means standard error of the mean (m scm). The relationships between from all four skinfold thickness measurements using the formula of Durnin and Rahaman (7), and Sin's formula (7) was used to determine the percentage of fat body mass. Lean body mass (LBM) was calculated by subtracting fat body mass from the total body mass. Leg volume (LV) was estimated using a modified version of the anthropometric method described by Jones and Pearson (18), wherein the leg is compared to a truncated cone. The formula to calculate the volume assessed
of a truncated cone is the following: l/3h(a+V(ab)+b), where h is the leg length (LL) expressed as follows: LL = Ht — SHt and a (upper-thigh circumference) and b (maximum calf circumference) are the areas of two parallel surfaces derived
from circumference measurements. Heymsfield's formula (15) was used to determine total muscular mass (TMM), which
can be expressed as follows: TMM (kg)=height(O.0264+ 0.0029AMA corrected). Gurney and Jelliffe's formulas (13) were used to determine arm muscle structure:
Muscular Circumference = Circumference of the Arm — t Tricipital Skinfold
Arm Muscular Area (AMA cm2) (muscular circumference)2/4it and the correcting factor is equal to — 10 cm2 for males.
Wmax, Vo, Fo, and age were tested by a one-way analysis of variance. A contrast test was performed when the ANOVA F ratio was significant (p < 0.05) (37). Correlation coefficients
were calculated to determine the relationships between Wmax, Vo, F, and the anthropometric characteristics (BW,
Ht, LL, LBM, LV, TMM). A multiple stepwise regression analysis was conducted in order to assess the relative contribution of anthroponietnic characteristics to the variation in the total variance of Wmax, V, and Fo values. Stepwise regression consists of selecting those variables which provide the best information for prediction using the partial correlation coefficients as a measure of the predictor importance of the variables. The coefficient of determination (r2) represents the overall fraction of variability for the predicted variable that is explained by the regression model. However, when many predictor variables
arc interdependent, the regression coefficients may not be stable from one population sample to another and, if not, cannot be used in a predictive mode. As this was the case, ridge regression was used to verify the stability of the regression coefficients.
Results
Age and mean values (± scm) of anthroForce-velocity test
All tests were conducted on a Monark cycle ergometer (model 864) with the boy in a sitting position. Each
pometric characteristics are listed in Table 1 for the seven age groups. The mean values (± scm) of Wmax, Vo, and Fo of the different age groups are shown in Fig. I (a, b, c). Wmax, Vo,
and Fo increased significantly between 11 and 19 years
(F=44.l, p
16, 27, 28, 29), which is performed against only one standard braking force. As Vandewalle et al. (34) have shown, this test
B. IViercier, J. Mercier, P. Granier, D. Le Gal-
lais and Ch. Préfaut, Maximal Anaerobic Power: Relationship to Anthropometric Characteristics during Growth. mt JSportsMed, Vol l3,No l,pp2l —26,1992. Accepted after revision: June 3, 1991.
The purpose of this study was to determine the effects of age in relation to anthropometric characteristics upon maximal anaerobic power of legs in sixtynine young boys aged 11 to 19 years. Maximal anaerobic power (Wmax) was measured by the force-velocity test.
does not measure maximal anaerobic power if the braking force is not optimal. Therefore, in order to study the effect of age upon maximal anaerobic power of legs with accuracy, it is advisable to use a test with incremental braking forces such as the force-velocity test. To our knowledge no studies have been carried out using the force-velocity test with leg during growth period. Recently, Vandewalle Ct al. (35) have measured arm maximal anaerobic power in young swimmers aged 12—18 years. These subjects were trained, however, and the respective roles of growth and training are difficult to differentiate. While there are some data on the relationship between anaerobic performance of legs and the various estimates of lean tissue (2, 5, 6, 16, 27, 29), there is no published information on the re-
Lean body mass (LBM) was determined from all four skin-
lationship between leg maximal anaerobic power measured
fold thickness measurements, leg volume (LV) was estimated by anthropometric method, and anthropometric measurements were used to determine total muscular mass
with the force-velocity test and lean body mass, leg volume, or total muscle mass in children. The purpose of this study, therefore, was to determine the effects of age in relation to anthro-
(TMM). Wmax increased significantly
(F 44.1,
pometric characteristics upon maximal anaerobic power of
p < 0.001) between 11 and 19 years and was correlated with LV (r = 0.84) and TMM (r = 0.88). It was most highly correlated with LBM (r = 0.94), which best explained the percentage of the total variance of Wmax (88%). Normalized Wmax (Wmax/LBM) also increased significantly be-
the legs measured by the force-velocity test during the growth period in sedentary children and adolescents.
tween 11 and 19 years (F = 21.9, p < 0.001). In conclusion, Wmax determined by the force-velocity test was closely re-
lated to anthropometric characteristics, especially LBM, during the growth period. Furthermore, even when corrected for lean body mass, maximal anaerobic power was always found to increase. This suggests that other undetermined factors, in addition to the amount of lean tissue mass, may explain the increase of Wmax during the force-velocity test. Key words
Growth, force-velocity test, maximal anaerobic power, anthropometric characteristics
Methods
Subjects Sixty-nine young boys, aged from 11 to 19 years, volunteered to participate in the present study. Written consent was obtained from the parents, as well as the approval from the National Ethical Committee. The boys had been informed of the procedures and purposes of the study. The tests were conducted during school hours in a special testing area set up at the school. All subjects included in the study underwent a complete clinical and electrocardiological examination. They participated only in the school physical education programs (3 hours a week). Subjects were classed into 7 homo-
geneous age groups; the range in the groups from 11 to 15 months. In the groups from 16 to 19 years, years was 1 year it was 2 years (Table 1).
Anthropometric characteristics Introduction
There have been numerous studies on the anaerobic power of legs in children and adolescents (2, 5, 6, 16, 23, 24, 25, 27, 28, 29). Most of them used the Wingate test (2, __________________________________________________ lnt.J.SportsMed.13(1992)21—26 GeorgThieme Verlag StuttgartNew York
Body weight (BW), standing height (Ht), and sitting height (SHt) were measured; extended upper-arm circumference, upper-thigh circumference, maximum calf cir. . . . cumference and bicipital, tricipital, subscapular, and suprailiac skinfold thicknesses were measured on the left side of the body. All measurements were taken by the same observer in the positions and following the techniques established by the International Biological Programme (36). Body density was
Downloaded by: University of British Columbia. Copyrighted material.
Abstract
mt. J. Sports Med. 13(1992)
B. Mercier, J. Mercier, P. Granier, D. Le Gallais, Ch. Prefaut
Table 1 Age groups and mean values (±sem) of anthropometric characteristics n
Ht
LL
BW
LBM
LV
TMM
)yrs)
(cm)
(cm)
(kg)
(kg)
(I)
(kg)
11
144.7 2.3
69.6 2
35.9
32.1
7.6 0.4
13.9 0.7
147.3
71.4 0.9
39.3
34.5
8.4
15.6
1.7
1.1
0.5
1.1
78.8 0.8
44.4
39.9
16.1
1.1
1
9.5 0.3
79.9
49.4
10.6
0.8
1.7
44 1.4
20.9 0.9
Age
groups 10
12
10
1.9 13
10
157.8
1.7 14
9
159
1.6 15
10
10
10
16.17
18.19
1.3
1
0.4
165.4 2.1
82
55.4
49.2
11.8
1
1.8
1.5
0.3
176.8
87.6 1.4
66.6 3.4
59.8 2.6
14
2.6 176.7
86.9 0.7
65.1 2.1
58.1
13.6
1.8
1.4
0.9
0.6
0.5
22.9 1.2 28 1.7 27.4 1.4
n = number of subjects, height (Ht), leg length (LL), body weight (BM), lean body mass {LBM), leg volume (LV), total muscular mass (1MM).
same exercise against a braking force increased by 1 kg. The first two exercises, done at low braking forces, were considered as a warm-up and familiarization with the test. We assumed that the subject attained the braking force corresponding to his maximal power if an additional amount of load in-
duced a power decrease. As previously described (22),
an
automatic system was used to determine the maximal velocity for each braking force and to calculate the force-velocity relations. As pointed out by Vandewalle et al. (31), the relation between braking force F and velocity V can be expressed as fol-
lows: V=b—aF or V=Vo—VIF/Fo=Vo(l—F/Fo) where Vo is the intercept with the velocity axis, i. e., maximal velocity
for braking force equal to zero, and Fo the intercept with the force axis, i. e., maximal braking force corresponding to velocity equal to zero. These were calculated by extrapolation of the linear relation linking the braking force and the velocity at a pedalling frequency greater than 90 rpm. This automatic system permitted us to verify that the maximal velocity for each braking force was achieved even for the youngest boys within
the 6 s. Given the linear force-velocity relationships, the power-velocity and ower-force relationship are parabolic. The maximal power ( max) was defined as the highest power value calculated for the different braking forces.
Statistics
All values reported are means standard error of the mean (m scm). The relationships between from all four skinfold thickness measurements using the formula of Durnin and Rahaman (7), and Sin's formula (7) was used to determine the percentage of fat body mass. Lean body mass (LBM) was calculated by subtracting fat body mass from the total body mass. Leg volume (LV) was estimated using a modified version of the anthropometric method described by Jones and Pearson (18), wherein the leg is compared to a truncated cone. The formula to calculate the volume assessed
of a truncated cone is the following: l/3h(a+V(ab)+b), where h is the leg length (LL) expressed as follows: LL = Ht — SHt and a (upper-thigh circumference) and b (maximum calf circumference) are the areas of two parallel surfaces derived
from circumference measurements. Heymsfield's formula (15) was used to determine total muscular mass (TMM), which
can be expressed as follows: TMM (kg)=height(O.0264+ 0.0029AMA corrected). Gurney and Jelliffe's formulas (13) were used to determine arm muscle structure:
Muscular Circumference = Circumference of the Arm — t Tricipital Skinfold
Arm Muscular Area (AMA cm2) (muscular circumference)2/4it and the correcting factor is equal to — 10 cm2 for males.
Wmax, Vo, Fo, and age were tested by a one-way analysis of variance. A contrast test was performed when the ANOVA F ratio was significant (p < 0.05) (37). Correlation coefficients
were calculated to determine the relationships between Wmax, Vo, F, and the anthropometric characteristics (BW,
Ht, LL, LBM, LV, TMM). A multiple stepwise regression analysis was conducted in order to assess the relative contribution of anthroponietnic characteristics to the variation in the total variance of Wmax, V, and Fo values. Stepwise regression consists of selecting those variables which provide the best information for prediction using the partial correlation coefficients as a measure of the predictor importance of the variables. The coefficient of determination (r2) represents the overall fraction of variability for the predicted variable that is explained by the regression model. However, when many predictor variables
arc interdependent, the regression coefficients may not be stable from one population sample to another and, if not, cannot be used in a predictive mode. As this was the case, ridge regression was used to verify the stability of the regression coefficients.
Results
Age and mean values (± scm) of anthroForce-velocity test
All tests were conducted on a Monark cycle ergometer (model 864) with the boy in a sitting position. Each
pometric characteristics are listed in Table 1 for the seven age groups. The mean values (± scm) of Wmax, Vo, and Fo of the different age groups are shown in Fig. I (a, b, c). Wmax, Vo,
and Fo increased significantly between 11 and 19 years
(F=44.l, p
