A recent study preprint shared on SportsRxiv investigated the impact of partial and full range of motion (ROM) resistance training on muscle growth in trained individuals. The results may surprise you.
Overview
- What did they test? Twenty-five resistance-trained adults had one arm randomly assigned to perform full range of motion (ROM) exercises, while the other arm performed partial ROM exercises. Training sessions occurred twice per week for eight weeks, focusing on upper-body exercises. Elbow flexor and extensor muscle thickness was assessed using ultrasound imaging, and muscle strength-endurance was evaluated using a 10-repetition maximum test on the lat pulldown exercise before and after the eight week training period.
- What did they find? The researchers reported that both partial and full ROM training resulted in similar increases in muscle thickness and strength-endurance.
- What does it mean for you? The findings of this study suggest incorporating partial ROM exercise variations into training can be as effective as full ROM exercises for promoting muscle growth, as long as the partial ROM emphasizes the lengthened position of the muscle (i.e., lengthened partials).
What’s the problem?
Prior research on the effects of performing lengthened partial range of motion (ROM) repetitions during resistance training on muscle growth has multiple limitations. Studies have primarily focused on lower-body muscles, with less research available on upper-body muscles. Additionally, most previous studies have not specifically targeted training at maximal, or near-maximal, muscle lengths. Muscle length refers to the length of a muscle relative to its attached articulating joint's safely achievable ROM. This has left a gap in understanding the benefits of such training. Further, most research has been conducted on untrained or recreationally active individuals, limiting the generalizability of findings to trained populations. This new preprint aimed to address these limitations by specifically investigating the effects of full ROM and partial ROM training on upper-body muscle hypertrophy in resistance-trained participants, with an emphasis on training at maximal muscle lengths.
Purpose
The purpose of this study was to compare the effects of lengthened partial repetitions (pROM) versus full range of motion repetitions (fROM) during eight weeks of resistance training (RT) on muscular adaptations in resistance-trained individuals.
Hypothesis
No hypothesis was explicitly stated, but the researchers alluded to previous studies that have suggested longer muscle length training might be more effective for muscle hypertrophy.
