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Back to Study: Neural determinants of the increase in muscle stre...
descriptive
Analysis v1
37
Pro
0
Against

Working out one arm can make the other arm stronger and more steady, even if you didn't touch it—your brain is learning to control it better.

Scientific Claim

Unilateral resistance training for four weeks increases maximal voluntary force by 6% in the untrained limb and improves force steadiness, suggesting neural adaptations occur without direct muscle loading.

Original Statement

“MVF increased in both the trained (+14%, P < 0.001) and untrained limbs (+6%, P = 0.004), and CovF decreased in both limbs (P < 0.001).”

From study:Neural determinants of the increase in muscle strength and force steadiness of the untrained limb following a 4 week unilateral training

Evidence Quality Assessment

Claim Status

overstated

Study Design Support

Design cannot support claim

Appropriate Language Strength

association

Can only show association/correlation

Assessment Explanation

The abstract reports an association between training and changes in the untrained limb but does not establish causation. The study design (observational cohort, no randomization stated) cannot support causal claims. Language like 'increases' implies causation.

More Accurate Statement

“Unilateral resistance training for four weeks is associated with a 6% increase in maximal voluntary force and improved force steadiness in the untrained limb, suggesting neural adaptations occur without direct muscle loading.”

Evidence from Studies

Supporting (1)

37
38

Neural determinants of the increase in muscle strength and force steadiness of the untrained limb following a 4 week unilateral training

Cohort Study
Human
2025 Jun

Training one arm made the other arm stronger and more steady—even though the other arm didn’t lift any weights—because the brain got better at sending clean, coordinated signals to the muscles.

Contradicting (0)

0
No contradicting evidence found

Source Study

Neural determinants of the increase in muscle strength and force steadiness of the untrained limb following a 4 week unilateral training

Score: 37
DOI: 10.1113/JP288954

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