Chain-loaded variable resistance warm-up improves free-weight maximal back squat performance
Abstract
The acute influence of chain-loaded variable resistance exercise on subsequent free-weight one-repetition maximum (1-RM) back squat performance was examined in 16 recreationally active men. The participants performed either a free-weight resistance (FWR) or chain-loaded resistance (CLR) back squat warm-up at 85% 1-RM on two separate occasions. After a 5-min rest, the participants attempted a free-weight 1-RM back squat; if successful, subsequent 5% load additions were made until participants failed to complete the lift. During the 1-RM trials, 3D knee joint kinematics and knee extensor and flexor electromyograms (EMG) were recorded simultaneously. Significantly greater 1-RM (6.2 ± 5.0%; p < .01) and mean eccentric knee extensor EMG (32.2 ± 6.7%; p < .01) were found after the CLR warm-up compared to the FWR condition. However, no difference (p > .05) was found in concentric EMG, eccentric or concentric knee angular velocity, or peak knee flexion angle. Performing a CLR warm-up enhanced subsequent free-weight 1-RM performance without changes in knee flexion angle or eccentric and concentric knee angular velocities; thus a real 1-RM increase was achieved as the mechanics of the lift were not altered. These results are indicative of a potentiating effect of CLR in a warm-up, which may benefit athletes in tasks where high-level strength is required. © 2016 European College of Sport Science
Keywords
1-RM, accommodating resistance, PAP, preconditioning, strength training, athlete, clinical article, controlled study, electromyogram, human, kinematics, knee function, male, resistance training, rest, velocity, warm up
Document Type
Journal Article
Date of Publication
2016
Publication Title
European Journal of Sport Science
Publisher
Taylor & Francis
School
School of Medical and Health Sciences / Centre for Exercise and Sports Science Research
RAS ID
21750
Copyright
subscription content
Comments
Mina, M. A., Blazevich, A. J., Giakas, G., Seitz, L. B., & Kay, A. D. (2016). Chain-loaded variable resistance warm-up improves free-weight maximal back squat performance. European Journal of Sport Science, 16(8), 932-939. Available here