Choose the next set before choosing the timer
You finish a set of push-ups and start the countdown. Thirty seconds, a minute, three minutes: which one is right? Start with what you want the next set to look like. Repeating a demanding strength exercise and moving through a timed circuit are different tasks. The shortest pause is not automatically the best choice.
Two studies, two different settings
A small randomized study followed 21 young men with resistance training experience for eight weeks. Three-minute rests produced greater gains in squat and bench press strength than one-minute rests, and greater growth in the measured front-thigh muscle thickness. This was a specific weight-training program, not a test of home push-up sessions. [1]
Another eight-week study, also with 21 participants in its long-term phase, used low loads and sets taken to failure. It compared 30-second and 150-second rests and reported no dependence of strength or muscle growth on rest length. Different training conditions matter; these small studies do not establish one ideal pause for everyone. [2]
Use the pause to serve the session
Our practical suggestion for repeated sets: leave enough time to approach the next set deliberately, rather than restarting simply because a countdown ended. If you keep losing repetitions or changing the movement to finish, review the exercise difficulty and effort as well as the pause. More rest is one variable to consider, not a diagnosis of what went wrong.
For a timed circuit, the work and rest periods are part of the task you chose. Shortening a pause changes that task. It may make the session feel harder without answering whether it better serves your goal.
When time is tight
Budget for rests before you start. Three sets have two between-set pauses: changing those pauses from one minute to two adds two minutes to the session. That is scheduling arithmetic, not a recommended rest prescription.
If the session no longer fits, consider fewer exercises or sets rather than automatically cutting every pause. Note the rest you actually took so that next time you compare similar sessions. A timer is useful for keeping track; it does not decide when you must continue.