If you lift weights until you're almost too tired to do another rep, you'll likely build bigger muscles—but your strength gains won't be any better than if you stopped earlier, as long as you're doing the same total amount of work and lifting the same weight.
Evidence from Studies
Supporting (4)
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Effects of resistance training performed to repetition failure or non-failure on muscular strength and hypertrophy: A systematic review and meta-analysis
This study found that lifting weights until you can't do another rep might help your muscles grow bigger, especially if you're already trained, but it doesn't make you stronger than stopping a few reps short—so you don't have to push to failure to get stronger.
This study found that lifting weights until you're almost out of energy (but not completely exhausted) builds muscle just as well as pushing until you can't do another rep — as long as you do the same total amount of work.
The study found that lifting weights until you're almost out of breath (but not completely exhausted) builds muscle just as well as pushing until you can't do another rep — as long as you do the same total amount of work. So, you don’t need to go all the way to failure to grow muscles.
Exploring the Dose–Response Relationship Between Estimated Resistance Training Proximity to Failure, Strength Gain, and Muscle Hypertrophy: A Series of Meta-Regressions
This study found that lifting weights until you're almost out of energy helps muscles grow bigger, but it doesn’t make you significantly stronger if you’re already lifting the same total amount of weight — which is exactly what the claim says.
Contradicting (0)
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