When training volume and intensity are the same, lifting weights with greater resistance at longer muscle lengths results in the same amount of muscle growth as lifting with greater resistance at...
Mechanism
Synthesis from 4 studies
Muscles grow the same whether you train them stretched or bent, because both ways create enough force and chemical buildup to turn on the same growth signal inside muscle cells. The body doesn't care where the tension happens—it only cares that enough stress is applied to trigger protein building.
Most probable mechanism
When muscles are worked under load, whether stretched or shortened, the force and buildup of metabolic byproducts trigger the same cellular growth signal, causing muscle fibers to add more protein and get bigger.
Resistance applied at any muscle length generates mechanical tension on sarcomeres and extracellular matrix, stretching actin-myosin filaments and activating mechanosensitive signaling complexes.
Metabolic stress from prolonged time under tension or vascular occlusion causes accumulation of lactate, hydrogen ions, and inorganic phosphate, activating metabolic sensors that converge on anabolic pathways.
Mechanical tension and metabolic stress independently and synergistically activate the mTORC1 signaling pathway, increasing ribosomal biogenesis and translation initiation.
Elevated protein synthesis rates lead to net accretion of contractile proteins, increasing myofiber cross-sectional area and muscle thickness across all regions of the muscle.
Less supported by current evidence, but not ruled out
Training at a specific joint angle improves the nervous system's ability to recruit muscle fibers at that angle, increasing strength there, but does not change how much the muscle grows.
Greater torque at extended elbow angles increases afferent feedback from muscle spindles and tendon organs.
Enhanced afferent input increases corticospinal excitability and motor unit recruitment efficiency specifically at the trained angle.
Neural adaptations improve force output at the trained joint angle without altering muscle protein synthesis or fiber size.
Evidence from Studies
Supporting (4)
Community contributions welcome
Placing Greater Torque at Shorter or Longer Muscle Lengths? Effects of Cable vs. Barbell Preacher Curl Training on Muscular Strength and Hypertrophy in Young Adults
The Effects of Long Muscle Length Isometric versus Full Range of Motion Isotonic Training on Regional Quadriceps Femoris Hypertrophy in Resistance-Trained Individuals.
Similar Regional Hypertrophy of the Elbow Flexor Muscles in Response to Low-Load Training With Vascular Occlusion at Short Versus Long Muscle Lengths
Contradicting (0)
Community contributions welcome
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.