AEROBIC FUNCTION DURING GROWTH
Armstrong, N., & Welsman, J. (1997). Children in sport and exercise. British Journal of Physical Education, 28(2), 4-6.
Aerobic Function
- The normal exhibition of maximum aerobic capacity is to demonstrate a plateau in oxygen consumption during an extended bout of work in a laboratory test. However, the majority of children and adolescents exercise to exhaustion without demonstrating a plateau. Therefore, the appropriate term to use with children and post-pubertal adolescents is peak VO2 (VO2peak), the highest VO2 elicited in a test to exhaustion. VO2peak is reliable and reproducible in children to the same extent that VO2max is in adults.
- When measuring aerobic parameters in children it is important to use sport-specific tasks if the information is to be related to training or a particular sport.
- VO2peak increases in boys by about 150% from 8 to 16 years while girls increase 80% during the same age-range.
- At 10 years, boys are about 13% higher than girls in aerobic capacity with the difference increasing to 37% at 16 years. In pre-pubertal children the VO2peak differences exist despite similar hemoglobin concentrations. Although boys are generally more active than girls it is unlikely that current physical activity patterns make a major contribution to aerobic capacity measures (VO2peak).
- Boys appear to possess a greater percentage of lean body mass than girls in the pre-pubertal years. If VO2peak is equated to body mass, VO2max in boys in childhood and adolescence is relatively consistent (49 ml/kg/min). On the other hand, girls are penalized by the accumulation of adolescent fat and their values progressively decrease from 45 to 39 ml/kg/min during the same period.
- Children's VO2max is as good as that of adults but their movements are less efficient, have a lower metabolic scope, have smaller stores of muscle glycogen, and are coupled with immature temperature regulation. Children are at a disadvantage when performing prolonged aerobic exercise when compared to adults.
- There is some evidence of a growth spurt in VO2peak in boys with the spurt reaching maximum near the time of peak height velocity. There are insufficient data to generalize about girls.
- The difference between VO2peak in boys and girls is more pronounced in mature adolescents. Hormonal changes during maturation do not appear to play an important role in the development of VO2peak.
Summary. VO2peak increases with age, growth, and maturation. Boys exhibit higher values than girls throughout childhood and adolescence but both sexes are relatively well-equipped to participate in aerobic exercise. Prolonged aerobic exercise in childhood must be approached with caution particularly in adverse environments (e.g., heat).
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