Introduction: Skeletal muscle hypertrophy as an effect of resistance training is dependent upon the range of motion used, among other factors. By manipulating this factor, we can isolate the specific muscles or muscle groups we want to model. When doing so, we can also affect the time of muscle under tension and contraction, both of which help to stimulate anabolic muscle processes. Purpose: The purpose of this diploma work is to review the literature researching how resistance exercise in different ranges of motion affect the hypertrophic response of skeletal musculature. Methods: A systematic review of 5 articles published up to January 2024 has been conducted. The articles have been found in the PubMed database by searching combinations of the following keywords: hypertrophy AND full range of motion, partial range of motion and exercise range of motion, respectively. Results: When time under tension is equalized and isokinetic concentric mode of resistance training is used, training with full range of motion has similar effect as training with partial range of motion for vastus lateralis muscle hypertrophy. With untrained individuals, resistance training at longer muscle lengths i.e., in the initial range of motion, has proven to be more efficacious than training at shorter muscle lengths, when the goal is hypertrophy of gastrocnemius muscle and distal portions of rectus femoris, vastus lateralis and biceps brachii muscles. In trained individuals training with partial range of motion is superior in eliciting triceps brachii hypertrophy in comparison to training with full range of motion. Discussion and conclusion: Because all of the studies published up to date are so heterogenous in nature, it is impossible to draw strong conclusions. But their results are mostly in favour of stimulating muscle hypertrophy by applying greater mechanical loads to muscles in their lengthened positions. Muscles also need to be stimulated under hypoxic conditions for enhanced growth hormone release. Different portions of resistance exercise optimally stimulate specific muscle parts or muscle groups, which welcomes further investigation as does this whole topic.
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