Q & A: How much time do muscles need to recover from a workout before you can work the same muscle group again?

In general, the rule of thumb has always been that you need to let muscles recover for at least 48 hours before you can do another round of resistance training with the same muscle group. This recovery time primarily allows the muscle to restore all of its short-term fuel sources that are stored within the muscle. While these aren’t the only fuel sources that the muscle has, the ‘in-muscle’ fuel sources are often critical when doing short, heavy training like resistance training. Thus, giving the muscle plenty of time to recover is actually beneficial (but not too much recovery or you will lose your training effect!).

Another reason for the 48 hours, though not primary, is to allow the muscle to start the ‘healing’ process. Some resistance training programs can cause small tears, called ‘microtears’ in the muscle tissue. These microtears are often the source of that soreness you feel after starting a new exercise program. While these microtears aren’t completely healed in 48 hours, this time gives the muscle a start on the healing process without doing further damage.

Now, none of this applies to continuous aerobic exercise like walking, jogging, or swimming. It is perfectly fine for you to exercise aerobically every day (and Doc Rocket recommends it….uuuuuhhhhh….and so do other organizations like the American College of Sports Medicine and the National Strength and Conditioning Association!).