If you’re keeping up electrolytes, there’s no problem with exercising. Most people can not keep up their usual intensity and some find it hard to push as hard as they can without feeling terrible. Others have no problem and while they might not hit their usual limits, can put in full effort without feeling off
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You’ll need to try it for yourself and see what works for you but most people will recommend lighter versions of your usual routine as a supplement to fasting. Personally, I can and do exercise on my fasts. My initial intensity doesn’t change much. Cardio (getting winded) gets worse. Winded recovery is WAY better/faster than normal. Muscle fatigue recovery time seems slower and less effective
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As an aside, if I fast and don’t exercise, my fast is usually a bit harder and I feel a bit worse than if I do