Lifting weights until you can't do another rep leaves you much more tired during and after the workout than stopping a few reps short — even if both methods build muscle equally.

Scientific Claim

Resistance training performed to momentary muscular failure results in consistently greater acute neuromuscular fatigue — measured by repetition and lifting velocity loss — compared to training performed with 1- to 2-repetitions-in-reserve in resistance-trained individuals.

Original Statement

“Lifting velocity and repetition loss were consistently greater for FAIL versus RIR, with the magnitude of difference influenced by the exercise and the stage of the RT intervention.”

Evidence Quality Assessment

Claim Status

appropriately stated

Study Design Support

Design supports claim

Appropriate Language Strength

probability

Can suggest probability/likelihood

Assessment Explanation

The RCT design supports causal claims about acute fatigue differences. The language 'consistently greater' is justified by the data presented and aligns with the study's measurement of objective fatigue markers.

Evidence from Studies

Supporting (1)

Similar muscle hypertrophy following eight weeks of resistance training to momentary muscular failure or with repetitions-in-reserve in resistance-trained individuals

Randomized Controlled Trial

Human

2024 Jan

Doing weightlifting until you literally can’t do another rep makes you more tired during the workout than stopping a few reps short — and this study proved it by measuring how much slower and fewer reps people could do when pushing to failure.

Contradicting (0)

No contradicting evidence found

Source Study

Similar muscle hypertrophy following eight weeks of resistance training to momentary muscular failure or with repetitions-in-reserve in resistance-trained individuals

Score: 54

DOI: 10.1080/02640414.2024.2321021

Similar Assertions

If you lift weights until you can't do another rep, or stop just before failure, your thigh muscles grow about the same amount after eight weeks — but stopping short feels less exhausting each time.

88%

Stopping a few reps short lets you do about the same total amount of work over weeks as going all the way to failure — because you can recover faster and do more sets without burning out.

79%

If you're already someone who lifts weights, doing light weights twice a week until you can't do more reps can make your muscles bigger and stronger in just 8 weeks.

78%

You don’t need to push to absolute failure to grow your thigh muscles — stopping just before failure works just as well and leaves you less tired, making it easier to train consistently.

77%

You can get stronger and bigger muscles by lifting light weights until you're exhausted — even if you never lift heavy, which challenges the old idea that heavy weights are required.

76%