Effects of final partial range of motion vs. full range of motion resistance training on muscle adaptations in physically active young men: a within-subject study

Purpose: The present study aimed to compare final partial range of motion (final pROM) vs. full range of motion (fROM) in muscle hypertrophy and maximal strength development in physically active young men. Methods: Ten physically active young men (age=22.90±2.47 years; body mass=83.85±11.67 kg; height=176.30±6.22 cm) participated in a randomized, intra-subject experimental design in which RT was performed using the upper- and lower-limbs with final pROM or fROM three times per week for six weeks. For all subjects, an arm or thigh was randomly selected and assigned for the final pROM condition, and the contralateral limb for the fROM condition. The subjects performed three sets of 12 repetitions at 60% of one-repetition maximum (1-RM), with two-minute rest interval between the sets and between limbs. The muscle hypertrophy of the elbow flexors and the knee extensors and the 1-RM test in the specific ROM that has been trained was measured before and after the intervention. An analysis of covariance was used to compare the different conditions on muscle hypertrophy and the maximal strength development. Results: The results showed that there was no statistically significant difference between the conditions for elbow flexors muscle hypertrophy (p=0.920; Cohen’s d=0.046) and knee extensors muscle hypertrophy (p=0.291; Cohen’s d=0.152). Similarly, there was no statistically significant difference between the conditions for 1-RM of the arm (p=0.161; Cohen’s d=0.898) and 1-RM of the thigh (p=0.276; Cohen’s d=0.533). Conclusions: Therefore, these findings suggest that there was no statistically significant difference between the different ROM, however, the moderate-large effect size (leg=0.533 and arm=0.898) in favor of final pROM in the maximal strength development, may indicate a potential direction for future research in physically active young men.