Support your bodyweight on your forearms and toes in a plank position with your feet together, keeping a straight line from shoulder to ankle.
Quickly hop your feet as far apart as you can, then quickly hop them back together.
Continue hopping your feet out and back in for a set number of repetitions or a set time limit before dropping out of the full planking position. Hopping your feet out and back in is one repetition.
This bodyweight move incorporates the motion of a jumping jack with the static hold of a plank to create an exceptionally brutal, yet very effective core and lower body exercise. With the number of muscles involved in this exercise, they can burn calories at a very high rate and build muscle and cardiovascular endurance quickly. Because of this, these are a good go-to move to add to a challenging fat burning workout or sports conditioning routine.