Lean back just a bit, maintain a straight back, and lift your feet off the floor. Twist your torso to the left, then to the right.
Lie down on your back, and place your hands at the back of your head. Lift your legs off the floor, and bend them.
Hold the plank for 30 seconds up to a minute. Slowly increase the amount of time you hold the plank as you progress.
Quickly alternate between bringing one knee to your chest, and then the next one, as if you're running in place.
Lift your hips to form a straight line from your head down to your feet. Hold this position for 20 to 30 seconds per side.
Lift your legs toward the sky, making sure they stay straight. Lower them without letting them touch the ground.
Raise your legs toward the sky, and curl your hips off the ground. Then, lower your legs, making sure they don't touch the floor.
Lie down on one side, and stack your legs. Raise your top leg toward the sky before lowering it.
Lower your chest toward the ground to perform a pushup. Then, jump your feet up to meet your hands.
Lift your right knee toward your right elbow as you crunch down.