Active versus local vibration warm-up effects on knee extensors stiffness and neuromuscular performance of healthy young males

Abstract Objectives To compare the effects of local-vibration and active warm-up on knee extensors muscle stiffness and neuromuscular performance. Design Experimental crossover study. Methods Thirteen participants performed three 15-min warm-up protocols of control (CON), active (ACT) and local-vibration (LV) in separate testing session. Passive stiffness of vastus lateralis (VL) and vastus medialis (VM) by shear wave elastography and neuromuscular performance were assessed before and 2-min after each condition. Results A decrease in muscle stiffness was reported after ACT for VL (−16.0 ± 6.6%; p   0.05) as well as central modulations as reported by the unchanged voluntary activation level (p = 0.24) and maximal electromyography (EMG) recorded from the VL (p = 0.44). Conclusions The active warm-up acutely reduced muscle stiffness and increased muscle performance during maximal dynamic tasks. With regard to LV, further studies are required to determine optimal parameters (frequency, amplitude, duration) to significantly increase muscle performance.