During unilateral strength training, the right arm often shows greater strength gains than the left, and this difference may be due to natural limb dominance or physical asymmetry, since the left arm...
Mechanism
Synthesis from 1 study
One arm is usually stronger than the other even before you start training, so when you work out just one arm at a time, the stronger one gets even stronger more noticeably. The weaker arm doesn’t improve as much not because it didn’t get enough exercise, but because it started behind and has less...
Most probable mechanism
One arm is naturally stronger than the other before training starts, so when both arms do the same workout, the stronger arm shows a bigger improvement because it has more room to grow and responds more to the stress.
Pre-existing interlimb differences in baseline muscle strength exist due to habitual use patterns and neural activation asymmetries.
During unilateral training, the limb with higher baseline strength exhibits greater absolute strength gains due to a higher capacity for neuromuscular adaptation and motor unit recruitment.
The limb with lower baseline strength shows smaller or nonsignificant gains, not due to reduced training response, but because it started at a lower functional capacity.
Evidence from Studies
Supporting (1)
Community contributions welcome
Small muscle mass exercise enhances muscular adaptations? Effects of unilateral and bilateral biceps curl on maximum strength and muscle size changes.
Contradicting (0)
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