The aim of this study was to verify the effects of blood flow restriction on movement
velocity and muscle activity during the back squat exercise. Methods: Twenty-four university
students participated in this study. In two randomized sessions 72 h apart, participants performed a
4-set protocol consisting of 30-15-15-15 repetitions performed at 30% of their one-repetition maximum
in the back squat exercise. In both sessions, neuromuscular function was monitored by surface
electromyography (EMG) and movement velocity (mean propulsive velocity (MPV), peak concentric
velocity (Vmax), and the effort index (EI)). Blood flow restriction (BFR) was applied during exercise
in one of the experimental sessions with 80% of full arterial occlusion pressure over lower limbs.
Results: The BFR condition showed higher (p < 0.05) EI, peak, and rooted mean square normalized
EMG in Set 1 compared to Set 2. Similar MPV and Vmax were observed in each set for both the
BFR and control conditions. No significant differences were observed between conditions in any
set. Conclusions: BFR did not imply changes in neuromuscular performance during low-intensity
resistance training, but it might induce greater intra-series velocity loss and less excitation of the
muscles involved.
