Acute effect of continuous running or cycling exercise on subsequent strength performance : A Concurrent training study

Abstract: Aim Aerobic exercise may interfere with subsequent responses to strength training. The aim of this research was to examine the acute effects of cycling or running on subsequent leg strength performance. It was hypothesized that eccentric contractions induced by running would impair strength performance more than the cycling mode of exercise, which consist mainly of concentric muscle actions. Method In order to investigate if continuous running or cycling affected following strength performance, 6 healthy individuals (5 males, 1 female) were subjected to a randomized cross-over design. Subject characteristics were age (year) 25,5 ± 2,1, height (cm) 180,5 ± 6,4, and body weight (kg) 83 ± 3,4. The experimental sessions included three protocols: strength protocol (S) which included 3 repetitions measuring peak power followed by 3 sets to muscular failure at 80% of 1RM in the squat exercise; and continuous running (RS) and cycling (CS) conditions (40 minutes at 80% of maximal heart rate), followed by the S protocol. Peak power performance and total work volume was measured. Results Average peak power attained between the three protocols were CS = 1639± 444Watts (W), RS = 1633± 422 and S = 1565 ± 349. No significant differences were observed between the three conditions (P = 0,817). No differences across the three protocols was observed for highest peak power attained by each subject (P = 0,619). Total work volume performed (main effect P = 0,027) revealed a significant difference between CS = 2559 kg and S = 3715 kg (P=0,037), and CS and RS = 3345 kg (P=0,037) due to the lower loads lifted in CS.  Conclusions There were no differences observed between the three training protocols regarding peak power performance. When cycling exercise was performed prior to the strength session, the total volume lifted was lower than when performing the strength test alone. Thus, it is concluded that cycling exercise, but not running, interferes with subsequent strength training performance.