Abstract
To evaluate the effect of a 9-week interval training program on aerobic capacity,
anaerobic capacity, and indices of anaerobic threshold of preadolescent boys, 28 10.2-
to 11.6-year-old boys were tested. The test included laboratory evaluation of anaerobic
capacity (Wingate anaerobic test) and evaluation of V̇O2 max and anaerobic threshold indices from a graded exercise test and measurement of
blood lactate. The tests also included a 1200-m run to investigate the relationship
of laboratory fitness indices, V̇O2 max, anaerobic threshold indices, and indices of anaerobic capacity to the performance
of the run. It was found that in 10- to 11-year-old boys, a 9-week interval training
increased the indices of anaerobic capacity: mean power by 10% and peak power by 14%.
No change was found in percent fatigue. The training also increased V̇O2 max by 7% in absolute terms and by 8%/kg body weight. A significant increase was
also found in the running velocity at the anaerobic threshold (running velocity at
inflection point of lactate accumulation curve), but in relative terms (percent of
V̇O2max), the anaerobic threshold decreased by approximately 4.4%. It is concluded that
proper training may improve maximal aerobic power and anaerobic capacity of preadolescent
boys. It is also concluded that anaerobic threshold measures are less sensitive to
the training regimen than V̇O2 max and that the 1200-m running performance is strongly associated with both aerobic
and anaerobic capacities and less with the anaerobic threshold, which in preadolescent
boys seems to be higher than in adults.
Key words
preadolescence - anaerobic threshold - V̇O2 max - anaerobic capacity - training - running performance
