Resumen:
The aim of this study was to analyse the quadriceps-hamstring coactivation in the lunge and Bulgarian squat exercises. A cross-sectional study design was applied to seventeen healthy professional football players. Muscular activity was measured using wireless surface electromyography (sEMG). The Maximum Voluntary Isometric Contraction was used to normalize the data. The muscle activation of each muscle belly was significantly different between the two exercises (F4.24 = 28.076, p < .001, partial ƞ 2 = .72). Activity in individual muscles varied in both the lunge (F4,24 = 49.315, p < .001,partial ƞ 2 = .89), and the Bulgarian squat (F4,24 = 28,076, p < .001,partial ƞ 2 = .82). The results showed no significant differences between the preferred and non-preferred legs of the participants (p > .05). In both the lunge and the Bulgarian squat, a significantly greater activation of the vastus medialis (VM) and the vastus lateralis (VL) muscles were found compared to the rectus femoris (RF) and biceps femoris (BF) and semitendinosus (ST). Muscles showed a greater activation during the Bulgarian squat compared to the lunge, but the hamstrings to quadriceps ratio was similar in both exercises (p > .05). Th...