No pain, no gain, as the exercise adage goes. But just how much pain do you have to endure to benefit from weight training? That depends on what you’re trying to accomplish, fitness experts say.

For years, some trainers have instructed gymgoers that to get the best results, they need to train “until failure,” meaning until you cannot physically do one more repetition or exercise. Some studies, however, suggest that this extreme regimen, when applied to weight training, may only benefit certain people.

“If somebody wants to increase muscle mass as much as they possibly can, then training to failure is something to consider,” said Michael Zourdos, chair of exercise science and health promotion at Florida Atlantic University, who co-wrote a review of 55 research papers on the subject in the journal Sports Medicine.

Zourdos and colleagues found that lifting weights “until failure” may build bigger muscles, but it isn’t needed to increase strength. He said people who work out hard but don’t push themselves to exhaustion will still likely improve their health and fitness. “There is a difference between training for health and training for elite performance benefits.”

For the average person simply looking to increase their fitness levels, Zourdos said it’s much easier to get results. He said people who work out regularly would benefit from an intense session that comes within five to 10 repetitions of failure, rather than training to complete exhaustion.

He also said “failure training” often comes at a cost, since people working to that standard might be so tired and sore that they skip their next gym session or two.

James Fisher, a sport science expert and consultant in Southampton, England, said the idea of working until complete exhaustion can be a turn-off for many people.

“What we’re really talking about is how hard you should work when you go to the gym,” he said. “If you’re short on time, then you can push yourself harder, and then you don’t need to work out as long.”

Fisher said the best workout is ultimately “one that people will actually do,” regardless of how hard they push themselves.