Recovery during high-intensity intermittent anaerobic exercise in boys, teens, and men

Purpose: This study examined the effects of age on recovery of peak torque of knee extensors (PTEX) and flexors (PTFL), and total work (TW) during high-intensity intermittent 30-s (H130) and 60-s (H160) exercise in boys (N = 19; age, 11.4 +/- 0.5 yr), teens (N = 17; age, 14.7 +/- 0.4 yr), and men (N = 18; age, 24.1 2.0 yr). Methods: Each age group's Subjects were subdivided to participate in an 11130 or an H160 protocol. The H130 involved 4 x 18 maximal knee extensions and flexions (1-min rest between sets), and the H160 comprised of 2 x 34 reps (2-min rest). PTEX (N(.)m(.)kg(-1)), PTFL (N(.)m(.)kg(-1)), and TW (J(.)kg(-1)) were recorded at each set. The percent recovery of PTEX, PTFL, and TW was calculated as percent of the value achieved in the first set. Results: In H160, the percent recovery for PTEX, PTFL, and TW after the first set was higher in boys compared with teens and men (P < 0.01). In H130, the percent recovery for PTEX, PTFL, and TW was higher in boys compared with men in all sets (P < 0.01), and in teens compared with men in the last two sets (P < 0,05). The percent recovery of PTFL and TW was higher in boys compared with teens in the last two sets (P < 0.05). Lactate increase was most pronounced in men, less pronounced in teens, and least pronounced in boys (P < 0.01). Heart rate recovered faster in boys compared with teens and men in both protocols (P < 0.05). Conclusions: The recovery was faster in boys than in teens and men during H130 and H160, as evident by the greater percent recovery in boys for a given time. Furthermore, it appears that the rate of recovery during H130 and H160 anaerobic exercise is maturity dependent.