Physiological Correlates of 3-Kilometer Running Performance in Male Children

The purpose of this study was to examine the influence of body fatness, aerobic and anaerobic ability on 3-km running performance in 19 physically active boys (mean ± SD, age = 10.4 + 0.9 yrs). The sum of six skinfolds, VO₂ at 8.04 and 9.65 km hr^-1 and VO₂max were measured in the laboratory. Run time for 3 km was assessed twice on separate days on a 200-meter indoor track. Prior to each run, every child performed two 55-meter sprints and two vertical jumps. Mean ± SD values for the sum of skin-folds, %VO₂max at each running speed, VO₂max and 3-km run time were: 33.9 + 14.9 mm; 70.6 ± 6.6 % and 81.0 ± 7.9 %; 54.6 ± 5.0 ml · kg^-1 · min^-1; 16.41 ± 2.58 min, respectively. Significant (p < 0.05) correlations were observed between the following variables and run time: sum of skinfolds (r = 0.72); vertical jump (r = -0.67); sprint time (r = 0.59); VO₂max (r = -0.61); and, %VO₂max at each treadmill speed (r = 0.79 and r = 0.75, respectively). Stepwise multiple regression analysis indicated that the combination of the %VO₂max at 8.04 km · hr^-1 and vertical jump accounted for 83 % (adjusted R²) of the variance in running time (SEE = 1.06 min, p < 0.05). This study suggests that 3-km run time in physically active boys is influenced by aerobic and anaerobic indices as well as body fatness, supporting the notion that children, compared to adults, are not metabolic specialists.

Aerobic capacity - submaximal oxygen uptake - anaerobic ability - distance running - boys