If you lift heavy weights, you get better at doing more reps with heavy weights; if you lift light weights, you get better at doing more reps with light weights — your muscles adapt specifically to the weight you use.

Scientific Claim

Resistance training with higher loads (80–90% 1RM) produces greater improvements in heavy-load absolute muscle endurance than lower loads (30–50% 1RM) in untrained young women, while lower-load training produces greater improvements in light-load absolute muscle endurance, indicating load-specific adaptations.

Original Statement

“HL training induced a larger improvement in heavy load AME (HL: 9.3 ± 4.3 vs. LL: 7.5 ± 7.1 repetitions, time × limb P < 0.01) and LL training induced a larger improvement in light load AME (LL: 24.7 ± 22.2 vs. HL: 15.2 ± 16.7 repetitions, time × limb P = 0.04).”

From study:Higher- and lower-load resistance exercise training induce load-specific local muscle endurance changes in young women: a randomised trial.

Evidence Quality Assessment

Claim Status

appropriately stated

Study Design Support

Design supports claim

Appropriate Language Strength

probability

Can suggest probability/likelihood

Assessment Explanation

Although this is an RCT allowing causal inference, the small sample size (n=16) and unknown blinding status limit confidence. 'Produces' is acceptable but should be qualified as probabilistic per EBM guidance.

More Accurate Statement

“Resistance training with higher loads (80–90% 1RM) is likely to produce greater improvements in heavy-load absolute muscle endurance than lower loads (30–50% 1RM) in untrained young women, while lower-load training is likely to produce greater improvements in light-load absolute muscle endurance, indicating load-specific adaptations.”

Evidence from Studies

Supporting (1)

Higher- and lower-load resistance exercise training induce load-specific local muscle endurance changes in young women: a randomised trial.

Randomized Controlled Trial

Human

2022 Dec 1

When women trained with heavy weights, they got better at lifting heavy weights; when they trained with light weights, they got better at lifting light weights — each type of training made them stronger in the exact way they trained.

Contradicting (0)

No contradicting evidence found

Source Study

Higher- and lower-load resistance exercise training induce load-specific local muscle endurance changes in young women: a randomised trial.

Score: 52

DOI: 10.1139/apnm-2022-0263

Similar Assertions

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