For exercise, I swim almost every afternoon after school. A regular practice schedule and other people to hold me accountable to what I do really helps. If I'm really having a bad day or something like that, I don't swim, but I try to get in at least some exercise, which might only consist of running from class to class at school rather than walking and taking my time.
My main suggestion: Find something you enjoy doing and find someone to hold you accountable so that you will actually follow through with your schedule. Don't start out so hard that you feel like you're going to quit a few days into it. Instead, start easy and build up to what you feel you should be doing. And don't be too hard on yourself if this takes a couple of tries to get right. Also, if you have a calendar or something, you can put a sticky note reminding you to exercise each day. Once you've completed your exercise, move the sticky note to the next day.
By the way, if you really don't want to run, you don't have to. There are other ways to get in cardiovascular exercise, and most aerobic workouts should work.
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Itaque incipet.
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