Both heavy and light weight training, done until exhaustion, didn’t change how hard participants could push or pull in a static muscle test after nine weeks.

Scientific Claim

Nine weeks of resistance training to muscular failure using either high-load (85% 1-RM) or low-load (30% 1-RM) protocols does not significantly alter maximal voluntary isometric contraction (MVIC) torque in young, recreationally-trained males.

Original Statement

“This study demonstrated similar MVIC and peak torque values for both isokinetic speeds...”

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

Evidence Quality Assessment

Claim Status

appropriately stated

Study Design Support

Design cannot support claim

Appropriate Language Strength

association

Can only show association/correlation

Assessment Explanation

The abstract explicitly states similarity in MVIC values with no indication of change or significance. No causal language is used, and the conservative association verb strength is appropriate given unconfirmed RCT design.

Evidence from Studies

Supporting (0)

No supporting evidence found

Contradicting (1)

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

Randomized Controlled Trial

Human

2024 May

The study found that lifting heavy weights didn’t hurt strength, but lifting light weights to failure might have slightly weakened it over time — so they’re not the same, even if the numbers didn’t change enough to be called 'significant'.

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

Similar Assertions

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