For people who already train regularly, doing more sets of weightlifting in a session or week does not lead to more muscle growth than doing fewer sets.
Mechanism
Synthesis from 1 study
When people who already lift weights do even more sets, their muscles hit a limit on how much they can grow — the signals that tell muscles to grow can’t go any higher. Adding more work doesn’t help because the system is already maxed out.
Most probable mechanism
When someone who already lifts weights does even more sets, their muscles stop responding to the extra work because the signals that tell them to grow have already turned on as much as they can. Adding more sets doesn’t turn them up any further.
Muscle protein synthesis signaling pathways, including mTORC1 activation, reach maximal stimulation after a certain number of resistance training sets.
Further increases in training volume do not produce additional activation of these signaling pathways beyond the saturated level.
Muscle growth is limited by the ceiling of protein synthesis rates, which are not further elevated by additional mechanical or metabolic stress from extra sets.
Less supported by current evidence, but not ruled out
Doing too many sets might make the muscles so tired that they temporarily shut down growth signals, canceling out any benefit from extra work.
Excessive training volume increases metabolic stress and intramuscular fatigue markers such as AMPK activation and intracellular acidosis.
Elevated fatigue markers inhibit mTORC1 signaling, reducing the efficiency of muscle protein synthesis despite increased mechanical load.
Evidence from Studies
Supporting (1)
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Contradicting (0)
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