It’s all about you. Crush as many jumping jacks as you can in those 30 seconds, and don’t worry if someone else does more. It’s not a competition; it’s just you, versus your personal best.

How To Do Plyo Jacks Plyo jacks are a little more involved than the classic jumping jack. But they’re still relatively easy to perform. Learn how to do them with proper technique via the step-by-step ...