European Journal of

Europ. J. Appl. Physiol. 36, 75--80 (1977)

Applied

PhyNology

and Occuoational F~hvsiology cO by Springer-Verlag 1977

Maximal O: Uptake of Boys and Girls - Ages 14--17 Francis J. Nagle, James Hagberg, and Sadatsugu Kamei* Departments of Physiology and Physical Education, University of Wisconsin, 2000 Observatory Drive, Madison, Wisconsin 53706, USA Summary. White high school girls (n = 120) and boys (n = 120) aged 14-17 years, selected from 9th, 10th, 1 lth and 12 grades of a northern, midwest U.S. high school performed running exercise on a motor driven treadmill for determinations of maximal O 2 uptake (Po2 max). The mean PO2 max for all age groups was 40.8 + 4.0 and 54.7 + 5.6 ml/kg - min -~ for girls and boys respectively. The difference in PO2 max across age groups varied only from 40.2-41.2 ml/kg, rain -1 for girls and 54.0--56.3 ml/kg 9min -1 for boys. These differences were not significant (P > 0.05). The reported PO 2 max data are compared with those reported in other studies for bicycle ergometer and treadmill exercise using similar age groups. Key words: Maximal aerobic power - Maximal aerobic capacity - Maximal O~ uptake.

Introduction Numerous investigators [2, 3, 7, 9, 12, 14, 15, 17, 18] have measured the maximal 0 2 uptake (VO 2 max) of male and female age groups. Such a profile on United States high school age individuals ( 1 4 - 1 7 years) is at best incomplete. The most comprehensive study is that by Knuttgen [ 10] who used the bicycle ergometer as the test instrument. It is commonly observed that VO 2 max values measured on the treadmill consistently exceed those measured on a bicycle ergometer [5, 7, 14] suggesting that Knuttgen's determinations fall short of maximal VO 2 values for this age group. It was our purpose to extend the PO 2 data profile on boys and girls 14-17 years using large sample sizes and a progressive treadmill test for the assessment of PO E max.

*

Department of Physical Education, Nagoya-Gukuin University, Nagoya, Japan

76

F.J. Nagle et al.

Methods The subjects in the study were 120 girls and 120 boys, 14--17 years of age. Thirty girls and 30 boys were randomly selected from 9th, 10th, llth and 12th grades in a northern, midwest U.S. public high school. Ninety girls and 90 boys in the randomly selected group were tested. The remaining subjects in each group were drawn from volunteers to bring each group to 120. The sample constituted 13% of the total student population. All subjects performed the test in gym clothes during school hours. Following height and weight measurements the subjects performed for 5 rain on a bicycle ergometer at a submaximal workload of 450 and 600 kpm/min for girls and boys respectively. The heart rate was measured for a 15 s interval in the 5th rain by carotid palpation. From this determination of heart rate, extrapolated to a minute value, a prediction of P'O2 max was made from Astrand's nomogram [2]. This exercise provided a warmup and the prediction of VOz max provided information for setting treadmill speed and grades to assure a treadmill test duration not exceeding 7 - 8 min [8]. The treadmill test which followed was performed at a constant speed of 135 m/rain (5 mph), 161 m/min (6 mph) or 188 m/min (7 mph). The grade was increased 2% each minute in all eases, the girls beginning at 0% and the boys at a 2% grade. The tests were terminated when the subjects indicated that they were not able to continue. The elapsed time for the tests varied from 4 - 8 mln with expired air collections being made over the terminal 2 - 4 rain of the tests. In every ease, the estimated ~-O2 requirement calculated from the speed and grade used in the terminal minutes of a test exceeded the measured ~'O2 max value. Estimates of ~'O2 requirements were made from the Margaria nomogram [11]. In most instances, the estimated P'O2 requirement oecuring during the gas collection periods exceeded 52.5 and 66.8 ml/kg, rain -1 for girls and boys respectively. Hence, there is no question that the exercise stimulus was intense enough to induce a P'O2 max response. Retesting of nine subjects revealed a difference of 97 ml O2 between testretest means. This was not significant (P > 0.05). Heart rates were measured by palpation of the carotid artery at the cessation of exercise. Measurements were made in the interval from 5-20 s of the 1st rain post exercise and this 15 s count was extrapolated to a l-rain value. This was done only to aid in the assessment of the effort intensity. The subjects expired air was collected through a wide bore breathing valve supported by a headband liner from an arc-welder's helmet. The valve was connected with low resistance tubing (i.d. 13/4 inches) to 2501 neoprene bags arranged in series. This allowed for continuous minute sampling of expired air. Aliquots of 100 ml were drawn from the neoprene bags for analysis of 02, CO2 and N2, in duplicate, on a Fisher-Hamilton Gas Partitioner. The ventilatory volumes were measured with a Tissot gasometer. For the statistical treatment of the (IO 2 data the analysis of variance procedure was employed.

Results I f the height-weight d a t a in T a b l e 1 are a d j u s t e d to nudity as the N a t i o n a l H e a l t h S u r v e y d a t a [13] are represented, the girls in this study w o u l d be 1.0 c m taller and a p p r o x i m a t e the a v e r a g e weight for the s a m e ages in the N a t i o n a l H e a l t h Survey. T h e b o y s , on the o t h e r h a n d w o u l d still exceed national a v e r a g e s b y a p p r o x i m a t e l y 2.4 c m in height and 3.0 kg in weight. S u c h differences f r o m national m e a n s c o u l d p r o b a b l y be e x p e c t e d in a middle to u p p e r - m i d d l e class c o m m u n i t y school as this was. In the treadmill tests, the m e a n m a x i m a l heart rate m e a s u r e d was 201.2 + 10.3 b p m for the girls a n d 200.6 + 13.2 b p m for the b o y s (Table 1). S u c h high rates, m e a s u r e d b y p a l p a t i o n i m m e d i a t e l y p o s t exercise, are u n d e r e s t i m a t e s o f p e a k heart rates but do suggest t h a t m a x i m a l efforts w e r e achieved. O n the a v e r a g e the m i n u t e ventilation (VE) values (Table 1) exceed t h o s e rep o r t e d b y A s t r a n d [3] but are l o w e r t h a n ventilations r e p o r t e d b y K n u t t g e n [ 10] for similar age groups.

Maximal Oz Uptake of Boys and Girls - Ages 14-17

77

The mean VO 2 max for all age groups was 40.8 + 4.0 and 54.7 + 5.6 ml/kg 9rain -1 for girls and boys respectively. The difference in VO2 max across age groups varied only from 40.2-41.2 ml/kg.min -1 for girls and 54.0-56.3 ml/kg 9rain -~ for boys (Table i). None of these differences across age groups was significant (P > 0.05).

Discussion

Wilmore and Sigerseth [17] obtained F-O2 max data for 10-13 year old girls tested on a bicycle ergometer. The 12 and 13 year olds (n = 22) averaged 48.7 + 1.9 ml/kg, min -1. The value is higher than those reported here for girls 14 through 17 years. National Health Survey data [13] show that the mean weight change for girls is from 4 6 . 4 - 5 0 . 3 - 5 4 . 0 kg over the 12th, 13th and 14th year. Wilmore and Sigerseth [17] reported mean weights of 49.0 kg for 12 and 13 year olds and we have reported a mean weight of 55.6 kg for 14 year old girls. These weights fit quite well with National Health Survey data [13]. Wilmore and Sigerseth [i 7] reported mean (zOz max values of 2.401/min for 12 and 13 year olds which is minimally different from the 2.27 l/rain we report for 14 year old girls (Table 1). The wide difference in mean f/O z max per kg between the two studies may be accounted for by the increase in body weight experienced between 12 and 14 years. Anderson and Ghesquiere [1] have shown a decrease in ~'O 2 max (ml/kg 9min -1) in females from 10-14 years of age. This was reportedly due to a proportionately greater increase in weight than in VO2 max (1/min) from the 10th-14th years. There was little variation in height and weight for girls between 14 and 17 years. In contrast the boys' body size changed markedly from 14-15 years and unlike the apparent pattern for girls 12-14 years, the change was accompanied by an increase in absolute (/702 max. This resulted in an increased PO 2 max expressed per kg of body weight (Table 1). From 15-16 years the boys show smaller increases in height and weight while the absolute (zO2 max and VO 2 max per kg are altered minimally (Table 1). The leO 2 values for a U.S. High school population are much higher than value reported by Matsui et al. [12] and Ikai and Kitagawa [9] for Japanese of the same age (Table 2). The former investigators used a bicycle ergometer and the latter a treadmill. The presently reported values are also higher by 10-18% for girls and boys respectively, than those reported by Knuttgen [10] for a similar population of Boston school children (Table 2). This difference is probably attributable to the fact that Knuttgen used bicycle ergometer exercise. The differences cited are within the 1 0 - 2 0 % difference in VO 2 max values observed when subjects are tested on both bicycle and treadmill devices [5, 7, 13]. Table 2 shows that leO z max data reported by -~,strand [3] for similar age groups far exceed the presently reported values. It is recognized that the sample represented a small number of select subjects. Recently, Vogel and Patton [16] reported treadmill measured [zO2 max data on male Army recruits who had completed basic and advanced infantry training (n = 234). Our mean [zO2 max for boys 14-17 years of 54.7 ml/kg 9rain -1 fits with their mean values of 53.3 + 5.0 ml/kg 9min -~ for 1 7 - 2 0 year olds (n = 73). Vogel and Patton [16] observed a further decline to 50.0 _+ 6.7, 46.5 + 6.7 and 43.8 + 6.3 ml/kg, rain -~ for 20-25, 2 5 - 3 0 and 3 0 - 3 5 year age groups respectively.

Boys 16.9_+0.48 n=30

Girls 17.0_+0.53 n=30 Boys 15.4_+1.2 n = 120

Girls 15.5-+1.2 n = 120

Total population

71.3 +11.1

58.4 + 6.8

66.6 _+11.1 57.1 _+ 8.1 (62.6) b (56.4) b

2.27_+ 0.25

41.1 _+ 3.7

3.16_+ 0.48

54.0 -+ 5.9

56.3 _+ 5.8

3.74• 0.31

a_+l SD b National Health Survey (1963--70) c Measured from 5--20 s of 1st rain post exercise

Max l"O 2 (ml/kg 9rain -1)

Max ~02 (1/min)

102.8 _+17.7 72.1 _+10.1 119.6 +12.7

41.2 _+3.7

2.30+0.28

77.9 -+9.6

54.0 _+ 3.5

3.71+_ 0.42 40.7 _+ 4.0

2.36+_ 0.34 54.7 _+ 6.7

3.87_+ 0.54

40.2 • 4.7

2.34+ 0.26

54.7 +_ 5.6

3.62• 0.52

78.1 +- 9.6 114.3 _+18.0

40.8 -+ 4.0

2.31_+ 0.28

77.7 _+10.9

195.7 +_10.8 198.9 • 7.6 195.9 +_12.4 202.8 +11.7 200.6 _+13.2 201.2 +10.3

58.2 _+ 9.0

115.0 +_18.3 82.9 _+11.6 119.9 +-19.0

68.9 _+ 8.7

Min. vent (~'e) BTPS l/rain

56.2 _+8.7

Girls 16._+0.41 n 30

177.2 -+ 5.5 164.7 +_ 6.0 179.3 -+ 6.5 163.6 _+ 8.8 175.4 _+ 7.8 164.3 _+ 6.8 (172.0) b (162.3) b

Boys 16.0_+0.18 n=30

Max HR (bpm) c 212.6 +11.1 199.6 +11.6 199.1 _+11.7 203.7 _+9.2

67.3 _+10.0

59.1 _+11.1 55.6 _+ 7.8

Weight (kg)

Girls 14.9-+0.55 n=30

169.3 _+ 8.9 163.8 _+ 6.2 175.3 + 6.9 165.0 +5.8

Boys 14.9-+0.52 n=30

Height (cm)

Girls 14.0_+0.18 n 30

Boys 13.8+_0.48" n=30

Age (years)

Table 1. Physical and physiological data on boys and girls 14--17 years

Z

c~

59.3 n = 5

47.1 + 6.3 n = 48

49.5 _ 3.7 n=19

~ s t r a n d (1952) (treadmill)

M a t s u i et al. (1973) (treadmill)

Ikai and K i t a g a w a (1972) (bicycle)

34.9 + 4.1 n=22

36.8 _ 5.6 n = 49

47.7 n= 5

41.1 +_ 3.7 n = 30

50.0 +_ 6.0

48.1 + 7.2 n=13

45.7 _+ 5.5 n = 47

59.7 n = 5

56.3 4- 5.8 n = 30

34.0 + 4.5

37.1 + 3.4 n=14

34.1 _+ 4.4 n = 54

44.7 n = 6

41.2 + 3.7 n = 30

Girls

a n = 95 ~ , n = 95 % Total s a m p l e size for 15, 16, 17 y e a r old b o y s and girls 9Oz m a x estimated f r o m figure

K n u t t g e n (1967) a (bicycle)

54,0 +_ 5.9 n = 30

Boys

Boys

Girls

15

14

A g e (years)

N a g l e et al. (1974) (treadmill)

Study

Table 2. C o m p a r i s o n s o f I)'O2 m a x ( m l / k g 9 min -a + SD) of h i g h school age b o y s and girls

49.5 _+ 7.0

47.2 • 4.5 n=19

49.2 _4 5.1 n = 50

59.0 n = 3

54.0 +_ 3.5 n = 30

Boys

16

34.5 + 4.0

34.3 + 4.1 n=18

34.7 _+ 5.2 n = 43

47.0 n= 8

40.7 • 4.0 n = 30

Girls

49.0 + 8.0

44.2 + 5.7 n=19

48.1 _+ 5.0 n = 38

58.2 n = 3

54.7 +_ 6.7 n = 30

Boys

17

33.0 _+ 4.0

34.4 _+ 3.7 n=9

38.5 +__5.8 n = 44

47.9 n= 2

40.2 +_ 4.7 n = 30

Girls

.~. I

I ;~

80

F.J. Nagle et al.

The comparison of the presently reported data with that of Vogel and Patton [16] on U.S. soldiers suggests that our VO~ max values m a y well be representative for the 1 4 - 1 7 year age group for the U.S. Furthermore the comparison suggests that the well documented decline in VO 2 max with age m a y begin before the start of the third decade of life for the U.S. male. Acknowledgements. We gratefully acknowledgethe assistance of WaUy Schessow and Gary Kolpin, Department of Physical Education, and the administrative staff of James Madison Memorial High School, Madison, Wisconsin.

References 1. Anderson, K., Ghesquiere, J.: Sex differencesin maximal 02 uptake, heart rate and on pulse at 10 and 14 years in Norwegian children. Hum. Biol. 44, 413-432 (1972) 2. Astrand, I.: Aerobic work capacity in men and women with special reference to age. Acta physiol. scand. Suppl. 49, 169 (1960) 3. Astrand, P.-O.: Experimental studies of physical working capacity in relation to sex and age. Copenhagen: Munksgaard 1952 4. Astrand, P.-O., Rodahl, K.: Textbook of work physiology. New York: McGraw Hill 1970 5. Chase, G. A., Grove, C., Rowell, L. G.: Independence of changes in functional and performance capacities attending prolonged bed rest. Aerospace Med. 37, 1232-1238 (1966) 6. Glassford, R. G., Baycroft, G. H. U., Sedgwick, A. W., McNab, R. B. J.' Comparison of maximal oxygen uptake values determined by predicted and actual methods. J. appl. Physiol. 20, 509-513 (1965) 7. Hermansen, L., Saltin, B.: Oxygen uptake during maximal treadmill and bicycle exercise. J. appl. Physiol. 26, 31-37 (1969) 8. Hermansen, L., Ekblom, B., Saltin, B.: Cardiac output during maximal treadmill and bicycle exercise. J. appl. Physiol. 29, 82-86 (1970) 9. Ikal, M., Kitagawa, K.: Maximal oxygen uptake of Japanese related to age and sex. Med. Sci. in Sports 4, 127-131 (1972) 10. Knuttgen, H.: Aerobic capacity of adolescents. J. appl. Physiol. 22, 655-658 (1967) 11. Margaria, R., Cerretelli, P., Aghemo, P., Sassi, G.: Energy cost of running. J. appl. Physiol. 18, 367-370 (1963) 12. Matsui, H., Miyashita, M., Miura, M., Kobayashi, K., Hoshikawa, T., Hamei, S.: Maximum oxygen intake and its relation to body weight of Japanese adolescents. Med. Sci. in Sports. 4, 27-32 (1972) 13. Metropolitan Life Insurance Company. Statist. Bull. 54, 8--9 (September, 1973) 14. Miyamura, M., Honda, Y.: Oxygen intake and cardiac output during maximal treadmill and bicycle exercise. J. app. Physiol. 32, 185-188 (1972) 15. Saltin, B., Astrand, P.-O.: Maximal oxygen uptake in athletes. J. appl. Physiol. 23, 353-358 (1967) 16. Vogel, J. A., Patton, J. F.: Aerobic power and body fat in a military population. Physiologist 18, 433 (1975) 17. Wflmore,J. H., Sigerseth, P. O.: Physical work capacity of young girls 7-13 years of age. J. appl. Physiol. 22, 923-928 (1967) 18. Wyndham, C. H., Strydom, N. B., Leary, W. P., Williams, C. G.: Studies of the maximum capacity of men for physical effort. Int. Z. angew. Physiol. 22, 285-295 (1966) Received May 3, 1976

Maximal O2 uptake of boys and girls -- ages 14--17.

European Journal of Europ. J. Appl. Physiol. 36, 75--80 (1977) Applied PhyNology and Occuoational F~hvsiology cO by Springer-Verlag 1977 Maximal...
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