Effects of submaximal and supramaximal interval training on determinants of endurance performance in endurance...

We compared the effects of submaximal and supramaximal cycling interval training on determinants of exercise performance in moderately endurance-trained men. Maximal oxygen consumption (VO_2max ), peak power output (P_peak ), and peak and mean anaerobic power were measured before and after 6 weeks (3 sessions/week) of submaximal (85% maximal aerobic power [MP], HIIT₈₅ , n = 8) or supramaximal (115% MP, HIIT₁₁₅ , n = 9) interval training to exhaustion in moderately endurance-trained men. High-intensity training volume was 47% lower in HIIT₁₁₅ vs HIIT₈₅ (304 ± 77 vs 571 ± 200 min; P < 0.01). Exercise training was generally associated with increased VO_2max (HIIT₈₅ : +3.3 ± 3.1 mL/kg/min; HIIT₁₁₅ : +3.3 ± 3.6 ml/kg/min; Time effect P = 0.002; Group effect: P = 0.95), P_peak (HIIT₈₅ : +18 ± 9 W; HIIT₁₁₅ : +16 ± 27 W; Time effect P = 0.045; Group effect: P = 0.49), and mean anaerobic power (HIIT₈₅ : +0.42 ± 0.69 W/kg; HIIT₁₁₅ : +0.55 ± 0.65 W/kg; Time effect P = 0.01; Group effect: P = 0.18). Six weeks of submaximal and supramaximal interval training performed to exhaustion seems to equally improve VO_2max and anaerobic power in endurance-trained men, despite half the accumulated time spent at the target intensity.