Source notes

A weight that feels equally heavy relative to your maximum does not allow the same repetitions in every exercise. Using data from nearly 7,000 people, drawn mainly from healthy study groups, researchers estimated how many repetitions could be completed at different percentages of a maximum single lift. At 80% of that maximum, the estimated average was about 13 repetitions for the leg press and 9 for the bench press. These were model estimates for sets continued until another repetition could not be completed, not recommended repetition targets or predictions for every individual.

People also differed around the average, especially at lighter relative loads. Sex, age, and training experience did not clearly explain the relationship in the available data, whereas exercise choice did. Lack of a clear subgroup effect is not proof that everyone responds identically. The estimates describe repetition capacity under the tested conditions; they do not show that taking every training set to failure produces better results.

How Does This Show Up in Real Life?

A useful application is interpreting a routine that assigns both a percentage of your maximum and a repetition count. The same instruction may leave different amounts of unused capacity in different exercises. For example, an identical relative load and repetition target should not automatically be assumed to mean an identical effort in the bench press and leg press. The authors provide separate estimates for these exercises and emphasize variation between people. Their tables can therefore inform expectations, but should not be treated as an exact requirement that your body must meet. The analysis used first-set performance, so it does not establish how many repetitions you will manage after several tiring sets. Nor does it tell you that a mismatch with an average means your training is failing.

The evidence was concentrated in bench and leg presses, healthy people, and younger or middle-aged groups. Other exercises and clinical populations were less well represented. The search process was not a standardized, fully reproducible systematic search. These limits affect how broadly the estimates can be applied; this was not a training intervention testing whether a prescribed routine produces lasting improvements.

Why We Cite It

Alpekin can use the reported variation to avoid false precision in digital exercise planning. Instead of displaying a calculated repetition number as a certainty, a tool could communicate that it is an estimate with room for individual differences. That turns uncertainty into useful information rather than hiding it behind an exact-looking interface.

These estimates are more informative than a universal conversion rule, but they remain estimates. Use the research to understand what a loading table can and cannot represent. A group average is a reference point, not a personal performance standard or a verdict on your progress.