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bioRxiv · 10.1101/2023.12.05.569582

The temporal recovery of contralateral and ipsilateral knee extensor torque following a bout of unilateral knee extensor resistance exercise in young, healthy resistance-trained men

Davies, R. W.·Barnes, H. L.·Carson, B. P.·Jakeman, P. M.
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Abstract

The present study aimed to characterise the temporal recovery pattern of contralateral-homologous torque following a bout of unilateral resistance exercise (RE). Ten young, healthy, recreationally active, resistance-trained men performed 10 sets of 10 repetitions of knee extensor (KE) contractions at 50 % 1RM with 1 min rest between sets. Isometric maximal voluntary contraction (MVC) peak torque (PT), surface electromyography (sEMG), muscle soreness and serum creatine kinase (CK) levels were assessed immediately before and 5 min after RE cessation, and then +4 h, +24 h, +48 h and +72 h later. Data are presented as mean [95 % CI] % change from pre-exercise values. RE evoked a minor increase in CK and pain in the late recovery period (+24 h to +72 h) (P < 0.034) and decreases in ipsilateral KE PT were observed immediately post-exercise (-26 [-33, -18] %, P < 0.001) and up to +48 h (-12 [-19, -4] %, P = 0.006). Measurable decreases in PT were also observed in the non-exercised contralateral KE immediately post-exercise (-8 [-13, -3] %, P = 0.006) up to +24 h (-8 [-15, 0] %, P = 0.020), but were significantly lower than the ipsilateral KE PT (P < 0.05). These findings suggest the presence of crossover fatigue following RE in young, healthy, active, resistance-trained men, however, the magnitude and temporal recovery are substantially less severe and protracted in the contralateral homologous KE.

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Davies, R. W., Barnes, H. L., Carson, B. P., Jakeman, P. M.. 2023-12-07. The temporal recovery of contralateral and ipsilateral knee extensor torque following a bout of unilateral knee extensor resistance exercise in young, healthy resistance-trained men. https://doi.org/10.1101/2023.12.05.569582

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