Lifting heavier weights for nine weeks made young men stronger in a max lift test than lifting lighter weights, even when both groups worked until they couldn't do another rep.

Scientific Claim

High-load resistance training (85% 1-RM) is associated with greater increases in predicted one-repetition maximum (1-RM) strength after nine weeks of training compared to low-load training (30% 1-RM) in young, recreationally-trained males.

Original Statement

“The high-load group showed greater increases in 1-RM following the training program.”

From study:Changes in muscular strength following nine weeks of high- or low-load resistance 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 uses language implying superiority ('greater increases') but does not explicitly confirm randomization or control for selection bias. Causal language is inappropriate without confirmed RCT design. Verb strength must be downgraded to association.

Evidence from Studies

Supporting (1)

Changes in muscular strength following nine weeks of high- or low-load resistance training.

Randomized Controlled Trial

Human

2024 May

People who lifted heavier weights got much stronger in a nine-week workout program than those who lifted lighter weights, even when both groups worked out the same amount.

Contradicting (0)

No contradicting evidence found

Source Study

Changes in muscular strength following nine weeks of high- or low-load resistance training.

Score: 37

DOI: 10.23736/S0022-4707.24.15569-7

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