• Posted August 2, 2024

Does Lifting Weights 'Close to Failure' Really Build Muscle?

A popular tactic among weight lifters is “training to failure” -- pushing yourself to the point where you can’t do a single more rep.

That might help a person grow bigger muscles, but won’t necessarily increase their overall strength, a new review published recently in the journal Sports Medicine finds.

People who stop their sets before their muscles completely give out will experience an improvement in strength similar to that of folks who train to failure, researchers found.

However, muscle size does benefit from training to failure, results showed. The closer a person is to failure when they stop their reps, the more muscle growth they tend to see.

“If you’re aiming for muscle growth, training closer to failure might be more effective,” said senior researcher Michael Zourdos, chair of the Florida Atlantic University Department of Exercise Science and Health Promotion. “For strength, how close you push to failure doesn’t seem to matter as much.”

For the review, researchers analyzed data from 55 prior studies that examined people’s repetitions in reserve, which means the number of additional reps a person could have performed before reaching muscle failure.

Results show that people who want to build muscle should train close to failure, which will optimize muscle growth while minimizing the risk of injury, researchers said.

For strength training, people should focus on lifting increasingly heavier loads, instead of pushing their muscles to failure, researchers said. They should stop about three to five reps short of failure.

The difference might come down to people’s perception of how much they can take, said lead researcher Zac Robinson, a doctoral graduate of Florida Atlantic University.

“When people estimate how many reps they have left, this perception influences the weights they choose. If the estimation is off, they might use lighter weights than needed, which could limit strength gains,” Robinson said in a university news release.

“On the flip side, our meta-analysis shows that training closer to failure also leads to greater muscle growth,” Robinson said. “So, for the average individual, training close to failure may be the best option -- as it seems to improve the accuracy of our perception of effort as well as gains in muscle size.”

More information

The National Academy of Sports Medicine has more about reps in reserve.

SOURCE: Florida Atlantic University, news release, July 31, 2024