It definitely has nothing to do with the exercise that you’re doing. On the other hand, it may have to do with your workout gear. Have you been sitting around in your sweaty outfit for far too long before hitting the showers? Try to change out of those smelly and sweaty gym clothes almost immediately after your work out and dry off before entering the shower. The back acne may be caused by the moisture and bacteria trapped by your workout gear.

Use a gentle scrub or loofah to exfoliate your back when you take a bath and use an acne gel that contains benzoyl peroxide or salicylic acid to kill the bacteria. You may also want to check that your sports bra that allows your skin to breathe while you exercise, rather than trapping the moisture in.