Calves Stretch
Begin in a push-up stance with your arms locked out at the elbows (so in the up-position of a push-up stance with your legs out straight and elbows fully locked; and this time it is perfectly ok to have your butt stick up in the air). Pick up one foot and use it to press down on the heel of the other foot. If you don't feel the tension in your calves, you may need to shift your body backwards a bit--effectively putting more weight working to push your foot closer to your shin.

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