A few reasons why I love Jumping Jacks:
1. Works your cardiovascular system
2. Builds Stamina
3. Working muscles in your: quads, shoulders, buttocks and calves.
How to perform a Cross Jack:
1. Jump into a wide squat, open arms to shoulder height, elbows bent. Your arms should look like a football field goalpost. (Looking at this picture this morning my arms need to be higher and in line with my shoulder. I lost my photographer to retake this picture:)
2. Jump to center, lowering arms and crisscrossing your right arm and left arm.
3. continue back to start, wide squat, goal post arms and alternate for 1 minute.
Great new exercise to incorporate in with circuit training, tabata, and intervals.