The Best Circuit-Training Workouts
Works: core, chest, triceps.
(A) Get in modified plank position, with forearms on the floor and elbows under your shoulders.
(B) Keeping your body aligned, press your palms into the floor and straighten your arms. Hold for two to five counts, then slowly lower your elbows to the floor and repeat.
Make it easier: Straighten one arm and then the other instead of both at once, or do the exercise from your knees.
Make it harder: Do the move with one leg raised.