EFFECT OF RANGE OF MOTION ON MUSCLE STRENGTH AND THICKNESS

Pinto, RS, Gomes, N, Radaelli, R, Botton, CE, Brown, LE, and Bottaro, M. Effect of range of motion on muscle strength and thickness. J Strength Cond Res 26(8): 2140-2145, 2012-The purpose of this investigation was to compare partial range-of-motion vs. full range-of-motion upper-body resistance training on strength and muscle thickness (MT) in young men. Volunteers were randomly assigned to 3 groups: (a) full range of motion (FULL; n = 15), (b) partial range of motion (PART; n = 15), or (c) control (CON; n = 10). The subjects trained 2 d.wk(-1) for 10 weeks in a periodized program. Primary outcome measures included elbow flexion maximal strength measured by 1 repetition maximum (1RM) and elbow flexors MT measured by ultrasound. The results indicated that elbow flexion 1RM significantly increased (p < 0.05) for the FULL (25.7 +/- 9.6%) and PART groups (16.0 +/- 6.7%) but not for the CON group (1.7 +/- 5.5%). Also, FULL 1RM strength was significantly greater than the PART 1RM after the training period. Average elbow flexor MT significantly increased for both training groups (9.65 +/- 4.4% for FULL and 7.83 +/- 4.9 for PART). These data suggest that muscle strength and MT can be improved with both FULL and PART resistance training, but FULL may lead to greater strength gains.