A comparison of full range and limited range of motion strength training
Crocker, John Edwin
In strength training, intensity is considered the most important variable for developing maximal strength. A possible way of increasing intensity is through the use of limited range of motion (LROM) strength training. Previous studies that have investigated LROM training have found conflicting results and have used questionable testing protocol. Thirty-one male university students were divided into three groups: a full range of motion (FROM) group (n=11), a LROM group (n=11), and a control group (n=9). All groups performed initial tests of the one repetition maximum parallel (1RM) squat and countermovement vertical jump (CMJ). The two experimental groups trained twice a week for seven weeks in supervised sessions that consisted of three sets of either parallel squats or half squats. All groups were monitored with respect to other activities they performed during the training period. Video analysis was performed on the training groups to compare movement patterns. The 1RM squat and CMJ were then tested again after the training period. The FROM group showed significantly (p < .05) greater increases in the 1RM squat and CMJ than the other groups. The LROM group showed significantly greater (p < .05) increases in the 1RM squat than the control group. The video analysis revealed the LROM group trained with a movement pattern that was significantly different (p < .05) than the FROM group. The results indicated that LROM training was not as effective as FROM training for the tested performances. However, the LROM training was found to be effective in increasing strength outside the trained ROM. The difference in the movement pattern between the two groups may have confounded the results because the FROM group trained with a movement pattern that was similar to the performances being tested.