Document Type : Original Article


1 Department of sport sciences, Azad University of Bojnord, Iran

2 Center for Biomechanics and Motor Control (BMC) Department of Sport Science University of Bojnord, Bojnord, Iran



Eccentric exercise has been commonly used as an intervention to improve muscle strength. However, change in neuromuscular activity over a fatiguing sustained contraction after eccentric training have received less attention The purpose of the current study was to investigate The effects of eccentric versus concentric resistance training on neuromuscular fatigue and strength of quadriceps muscle Methods: 24 male subjects recruited for this controlled laboratory study. Subjects were randomly divided into two groups, eccentric training group (No= 12), and concentric training group (No=12). Maximal knee extension force and surface electromyography (EMG) signals were recorded before and after 12 weeks resistance eccentric and concentric trainings. Muscle fiber conduction velocity (MFCV) and root mean square (RMS) were computed from raw EMG signals. Results: Eccentric training contribute to a higher increase in MFCV and RMS of EMG as compared to concentric exercise (P < 0.05).Moreover, MFCV rate of reduction over sustained contraction for eccentric group was significantly higher than concentric group (P < 0.05). Conclusion: A higher reduction in MFCV observed after eccentric training can underestimate the value of this type of training to improve neuromuscular fatigue


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