In people who regularly lift weights, training the elbow flexor muscles through a limited range of motion that stretches them under load may lead to slightly more muscle growth in the lower part of...
Mechanism
Synthesis from 1 study
When you lift weights with your muscle stretched at the bottom and don’t fully shorten it, the stretched part feels more tension, which tells the muscle to grow more protein right there. This makes the part closest to the elbow a little thicker than if you had moved through the full range.
Most probable mechanism
When a muscle is held in a stretched position while under load, the fibers and surrounding structures experience more pull, which triggers a chemical signal inside the muscle cells that tells them to build more protein. This happens most strongly in the part of the muscle farthest from the joint, leading to thicker growth in that specific area.
The muscle is held at or near its maximum physiological length during concentric and eccentric contractions, increasing passive tension in sarcomeres and extracellular matrix structures.
Elevated mechanical tension activates intracellular signaling pathways, particularly the mammalian target of rapamycin complex 1 (mTORC1), which increases ribosomal biogenesis and the rate of muscle protein synthesis.
Mechanical strain is greatest in the distal regions of the muscle, closest to the tendon insertion, leading to localized upregulation of protein accretion and sarcomere addition in those areas.
Accumulated protein synthesis results in increased cross-sectional area of muscle fascicles, measurable as greater muscle thickness at the distal region.
Evidence from Studies
Supporting (1)
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Contradicting (0)
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