The following is adapted and extended from something I just wrote to my mother,. She’s been going to her gym four times a week, and had mentioned that someone told her she was stressing about about her workouts. Below is my entirely biased and unscientific answer to how many times a week people should work out – I thought this might be useful for other people as well. It’s aimed at people who aren’t athletes or in training for a specific event, because people who are should have a training plan, with periodization and all that kind of thing to avoid overtraining and build capacity. (There’s a fascinating, if slightly insane, discussion of building a rowing training program here.)

A lot of it will depend on your athletic history, your level of fitness and your goals. Four times a week for an hour a day is a good bit for someone like my mom who’s exercising more for fitness than a specific goal, but it’s nothing to a marathon runner in training. It also depends on what kind of workout you’re doing and on your available free time. Maybe running every day would be too harsh on your joints but you can substitute yoga or cycling. It also depends on how you yourself function. Maybe you have an especially busy schedule and four classes a week will stress you out, or maybe those classes give you a place to recover from the rest of your life.

It’s a very individual thing; you just have to decide if you feel better both mentally and physically when you go that often. If so, you’re fine. If not – if you’re in better shape but feel stressed OR if you feel great mentally but your body feels overworked, then cut back one workout, or try changing one to see if a different type of workout helps. Different types of workouts help anyway, in terms of both physical fitness nad avaoiding mental fatigue; you need to balance stength, aerobic capacity and flexibility / balance.

Listen to your body, selectively. You need to push it a bit, because if you always did what it wanted you’d probably just stay on the couch. On the other hand, there are times when you’re heading off to the gym and it says “NO”. I think you ought to listen to it. (This applies even to athletes in training, though the more fit you are and the more important the event you’re training for, the more your body might need to force its objections on you. A signal that should persuade a casual member of an aerobics class to stay home is not going to knock an Olympian off her planned training regimen, and it shouldn’t – but even the Olympian might need to take a very rare unplanned timeout to avoid physical or mental overtraining.

Finally, don’t expect there’s one single answer for always, either. Depending on how the rest of your life is going, you
might easily handle at some times what’s too much for you at other times. Then again, mindless physical activity might be a perfect antidote to an emotional upheaval.

When I was doing my Six Sigma training, they told us the standard Black Belt answer: “It depends.” Others might disagree, but I think that’s the answer here, that and “listen to yourself”.