How long do you have to wait before starting to exercise again after having mono?

No set time: First depends how sick you were, and if you had a complication like an enlarged spleen. If the latter, then it is important to avoid contact sports or some exercises until it is back to normal. Otherwise, general guidelines make sense - start back slow, remember to stretch, stay hydrated and respect your body's need to recover.Base things on how you feel and do not "push through" until stronger.

Go slowly: First, make sure your spleen does not get subjected to possible injury during your exercise. Then progress slowly and only until you begin to experience fatigue. It may take some time until you feel entirely whole again. This can be a bad disease.