Jumping jacks are one of the simplest but most exhausting exercises you'll encounter. Jumping Jacks recruit nearly every muscle group in your body and provide a phenomenal cardio workout.
To perform them, stand straight up with your feet about six inches apart. Your arms should be at your sides. Then, jump upwards and bring your legs out to your sides, wider than shoulder width.
At the same time lift your arms up and out bring them together so they touch over your head. Next, jump up and bring your legs back to the starting position while simultaneously also returning your arms to the starting position at your sides.