Total Time: 25 minutes Rest for 30 seconds after each exercise and repeat the circuit three times. Take a four-minute break between sets. Plank Hold for 30 seconds Each workout, try to add at least three extra seconds. Once you can comfortably hold the plank for a minute, try adding flutter kicks. Lift one foot two inches off the ground for ten seconds and then switch feet. Side Plank Hold for 30 seconds each side Try adding at least three seconds to the side plank each workout. Bicycle Crunch 10 reps on each side Keep your lower back flat on the ground. Extend your leg slowly and controlled during each rep. Add an extra rep each workout. Flutter Kicks 10 reps on each side Keep your lower back flat on the ground. Extend your leg slowly and controlled during each rep. Add an extra rep each workout.