CAN MUSCLE FATIGUE IN WOMEN BE INFLUENCED BY KNEE EXTENSION TASKS IN DIFFERENT RANGES OF MOTION?

Purpose. The present study aimed to compare the strength performance in the one-repetition maximum (1rM) test with a knee extension machine among different ranges of motion (rOMs), and to compare the force reduction after the performance of a dynamic exercise configured with different rOMs. Methods. Nine women (mean ± standard deviation: age: 24.2 ± 3.5 years; height: 166.5 ± 4.1 cm; body mass: 68.35 ± 4.14 kg) with no strength training experience and no history of injury performed (cross-over design) tests of 1rM with a knee extension machine in the following rOMs: 100–65° of knee flexion (INITIAL), 65–30° (FINAL), and 100–30° (FULL) (0° = knee full extended). Further, the volunteers performed, in each rOM, 3 sets of 7 repetitions at 60% of 1rM (specific to rOM assessed) with 3-minute rests between sets with 2 seconds for concentric and eccentric phases. Before and 2 minutes after the training, the maximum torque values at 100° and 30° of knee flexion were registered to calculate the force reduction. Results. The ANOVA test identified that the maximum torque pre-training values were greater than the post-training values (p = 0.02), and a greater torque reduction occurred at 30° of knee flexion than at 100° (p = 0.001). Conclusions. The results suggest that rOM may influence maximum strength performance, and the force may reduce similarly along the angles.