In trained young men, performing resistance training with many repetitions and lighter weights for six weeks leads to a 69% higher rate of protein synthesis in non-muscle fiber components of the...
Mechanism
Synthesis from 1 study
Doing lots of reps with lighter weights causes muscle cells to release more calcium during each contraction. This calcium turns on a signal that tells the cell to build more proteins that help with energy, not muscle size. Over six weeks, this leads to a bigger pool of metabolic proteins inside the...
Most probable mechanism
When someone does many repetitions with lighter weights, their muscle cells get flooded with calcium each time they contract. This calcium surge turns on a molecular signal that tells the cell to make more proteins that help with energy production and cell metabolism, not the ones that make muscles bigger. Over time, this leads to more of these metabolic proteins building up inside the muscle.
Repeated high-repetition contractions during high-volume training increase intracellular calcium flux in muscle fibers
Elevated intracellular calcium activates MAPK signaling pathways (e.g., ERK1/2)
Activated MAPK signaling upregulates translational machinery for non-myofibrillar proteins (e.g., metabolic enzymes, sarcoplasmic proteins)
Increased synthesis of non-myofibrillar proteins leads to accumulation of sarcoplasmic components without proportional myofibrillar growth
Evidence from Studies
Supporting (1)
Community contributions welcome
Effects of High-Volume Versus High-Load Resistance Training on Skeletal Muscle Growth and Molecular Adaptations
Contradicting (0)
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