Resistance move: The standard pushup
With your hands and feet on the floor, your arms parallel and shoulder-width apart, and your legs straight behind you, lower your body toward the floor (keeping your arms at your sides), then push up to return to a plank position. Repeat. Modification: Hold a plank position with your arms straight and shoulder-width apart. Focus: Chest, shoulders, triceps and abs. Reps: Do as many as you can with good technique. Tip: If you do pushups on your knees, you won’t engage your core. If you can’t lower your body all the way down in standard pushup form, Horton recommends doing a half or mini pushup instead.
Cardiovascular move: Running on the spot
Modification: Marching on the spot, jumping jacks and boxing moves such as cross hooks or uppercuts Focus: Raising your heart rate Reps: Go as fast and as furiously as you can handle for one minute. Tip: There are no rules—just move your body as much and as fast as you can.
Core move: The bicycle
Lie on your back with your hands clasped behind your head, your knees bent and your feet lifted off the floor. Extend your right leg and reach your right elbow toward your left knee. Change to the opposite side, extending your left leg and reaching your left elbow toward your right knee. Continue changing sides, cycling your legs as if you’re on a stationary bike and always reaching your elbow toward the opposite knee. Modification: Any lie-down ab exercises, such as scissors or ticktocks (lift your legs straight toward the ceiling and move them in a circular motion, keeping your torso stable). Focus: Abdominal muscles Reps: Start with 20 reps and work up to 30. Tip: Every time you exhale during a move, contract your abs as much as possible. Always protect your lower back—if it hurts, try a different position.