When predicting how much muscle a person will gain from training, accounting for how much they have trained in the past makes the prediction more accurate.
Mechanism
Synthesis from 1 study
People who’ve lifted weights for a long time need heavier loads or more reps to grow more muscle — their muscles have already gotten used to lighter loads. If you don’t know how much they’ve trained before, you might think they’re not responding well, when really their body just needs more stress...
Most probable mechanism
When someone has lifted weights a lot before, their muscles don’t respond as strongly to the same amount of lifting as someone new — their muscles have already grown as much as they can with that level of stress, so adding more weight or reps is needed to make them grow more.
Prior resistance training leads to adaptations in muscle fiber size and satellite cell content, reducing the relative anabolic stimulus from a given training volume.
This results in diminished activation of mTORC1 signaling and reduced rates of muscle protein synthesis per unit of mechanical load.
Without accounting for prior volume, individuals with high training history appear to respond poorly to standardized protocols, not due to lack of potential, but because the stimulus is insufficient relative to their adapted state.
Evidence from Studies
Supporting (1)
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Contradicting (0)
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