The acute effects of varying strength exercises bouts on 5Km running.

This study investigated if there were acute interference effects of strength exercises on subsequent continuous and intermittent 5Km aerobic exercises. Eleven physically active males (23.1 ± 3.1 yrs, 1.75 ± 0.07 m, 70.5 ± 8.8 kg, and 58.2 ± 8.3 VO2max) performed the following experimental sessions: A) 5 sets of 5 RM on the leg press followed by a 5km run performed continuously (average velocity of the first and second ventilatory thresholds, vΔ50), B) 5 sets of 5 RM on the leg press followed by a 5km run performed intermittently (1 min run at the vVO2max : 1 min of rest); C) 2 sets of 15 RM on the leg press followed by a 5km continuous run; and D) 2 sets of 15 RM on the leg press followed by a 5km intermittent run. Heart rate, blood lactate concentration, rate of perceived exertion, and VO2 at the first and the fifth km were considered for statistical purposes. There were no significant effects of both strength bouts on any of the variables associated with endurance performance (p > 0.05). It seems that both maximum and strength endurance bouts do not acutely impair aerobic performance. Key pointsResidual acute peripheral fatigue does not seem to be the only cause in the interference effect observed during concurrent training regimens.Peripheral fatigue mechanisms of running such as lactate concentration are not altered by prior lower volume strength exercises.Strength and strength endurance exercises performed before a running bout do not seem to impair the performance in the latter.