In a study comparing training methods, only the traditional training group showed consistent, measurable differences in strength gains, while changes in muscle size and strength in the non-trained...
Mechanism
Synthesis from 1 study
When muscles grow a little or a non-trained arm gets slightly stronger, the tools used to measure it aren't precise enough to tell real changes from random mistakes. But when people get much stronger from lifting heavy weights, the change is big enough to be seen clearly — so only those gains look...
Most probable mechanism
When measuring small changes in muscle size or strength in arms that weren't trained, the tools used aren't precise enough to tell real changes apart from normal random noise. This makes it look like no one is truly responding, even if some people are. But when people lift heavy weights in a way that strongly challenges their muscles, the strength gains are big enough to stand out clearly from the measurement noise.
Muscle hypertrophy and cross-over strength changes are small in magnitude and occur gradually over time, resulting in signal amplitudes near the detection limit of current measurement technologies.
Measurement tools for muscle size and untrained limb strength have inherent technical variability due to factors like probe placement, tissue hydration, and imaging resolution, introducing random error that obscures small biological changes.
Strength gains from traditional resistance training are larger in magnitude due to increased neural drive and motor unit synchronization, producing a signal that exceeds the threshold of measurement noise.
Evidence from Studies
Supporting (1)
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Assessing differential responders and mean changes in muscle size, strength, and the cross-over effect to two distinct resistance training protocols.
Contradicting (0)
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