So for the first two semesters I went to TKD three times a week. The workouts were pretty intense: lots of blocks and punches up and down the gym, kicks in place, calisthenics. A few times we did jumping kicks and punches down the length of the gym.
I would also walk across campus to the gym and get there about 30 minutes early. I would go through the stretching routine before class. I got pretty flexible pretty fast.
I do not remember if I did any exercise on the off days.
During breaks I would do kicks, punches and blocks in the basement.
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