Moderate evidence

A single hard set per exercise, once to three times a week, is enough to increase strength in trained men.

In practice

On a week where everything is going wrong, one working set is not a wasted session — it's most of the maintenance benefit. Doing something small beats skipping.

What it doesn't say

This is the minimum to keep gaining strength, not the amount that maximises anything, and the studies were in resistance-trained men. Size responds to volume far more than strength does.

Source

• Androulakis-Korakakis P, Fisher JP, Steele J (2020). The minimum effective training dose required to increase 1RM strength in resistance-trained men: a systematic review and meta-analysis. Sports Medicine, 50:751–765. doi.org/10.1007/s40279-019-01236-0