If you train one leg at a time, that leg gets much stronger than the other when tested alone — but if you train both legs together, both legs get stronger at the same rate, with no one leg getting ahead.

Scientific Claim

In young women, unilateral training leads to lateral specificity in strength and neural activation gains — improvements occur primarily in the trained limb during unilateral tests — while bilateral training does not produce this specificity, enhancing both limbs equally.

Original Statement

“Only UG showed greater values than CG in the unilateral 1RM test at post... UG showed a greater (p ≤ 0.05) increase in unilateral than in bilateral whereas the BG was not different.”

From study:Neuromuscular Adaptations to Unilateral vs. Bilateral Strength Training in Women

Evidence Quality Assessment

Claim Status

appropriately stated

Study Design Support

Design supports claim

Appropriate Language Strength

definitive

Can make definitive causal claims

Assessment Explanation

The RCT design with separate unilateral and bilateral strength testing before and after allows definitive claims about training-induced lateral specificity.

Evidence from Studies

Supporting (1)

Neuromuscular Adaptations to Unilateral vs. Bilateral Strength Training in Women

Randomized Controlled Trial

Human

2016 Jul

When women trained one leg at a time, that leg got stronger than the other — but when they trained both legs together, both legs got equally stronger.

Contradicting (0)

No contradicting evidence found

Source Study

Neuromuscular Adaptations to Unilateral vs. Bilateral Strength Training in Women

Score: 47

DOI: 10.1519/jsc.0000000000001125

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