Plank
Why: By keeping your belly button drawn in and challenging your stability throughout your shoulders, core, and hips, you’re building strong abs.
How: Lie in a prone pushup position with forearms resting on the floor, elbows under shoulders and bent 90°. Push up off your elbows, tucking your chin so your head is in line with your body. Keep head inline with your spine, and belly button drawn in. Hold for one minute.
Prescription: 2 sets of 60 seconds with 60 seconds rest between sets.
Side-plank
Why: The side-plank targets the obliques more than a traditional plank.
How: Start on the ground on your left side with your left forearm on the ground and your elbow under your shoulder. Push up off your elbow, creating a straight line from ankle to shoulder. Your hips should be off the ground and only the side of your bottom foot, and your elbow should be on the ground. Hold for 30 seconds or do 10 reps of 3 seconds each.
Prescription: 2 sets of either of the above options.
Flutter Kicks
Why: If it’s good enough to challenge the Navy SEALs as a staple of their training, it’s good enough for you. You need not do it while cold, wet, and sandy, though.
How: Lie on your back, legs straight, and arms extended at your sides. Lift your heels six inches and rapidly kick up and down in a fast, scissor-like motion.
Prescription: 2 sets of 60 seconds with 60 seconds rest between sets.
Hanging Legs Raises
Why: This challenges you to raise your entire lower body with your abs and hip flexors, a key part of core strength.
How: Grab a pullup bar with an overhead grip. Arms should be straight and feet off the ground. Keeping the legs straight, use your abs to raise your feet toward your shoulders, pausing when your thighs reach your chest.
Prescription: 2 sets of 10 reps with 30 seconds rest between sets.
Oblique Mountain Climbers
Why: Like a mountain climber working a wall, you’re using the abs and hip flexors to “climb”. This variation really targets the obliques as you bring your legs across your body while crunching.
How: Start in pushup position, with the balls of your feet on the ground. Alternate driving your knees forward to the opposite arms, twisting your body to that side, for 30 seconds. Keep your hips down for the entire motion.
Prescription: 2 sets of 10 reps with 30 seconds rest between sets.
Reverse Crunch
Why: This targets the entire core region while also stretching your lower back.
How: Lie on your back, knees together, and legs bent to 90°. Feet should be on the ground and hands palms-down. Tighten your abs—think of bringing your bellybutton away from your waistband—and lift your hips off the floor, crunching your knees to your chest. Pause at the top and then lower back down. Do not allow your lower back to arch and lose contact with the floor.
Prescription: 2 sets of 10 reps with 30 seconds rest between sets.
Burpee
Why: This full-body exercise challenges your cardiovascular system and ratchets up the intensity of your workout. It’s a common penalty for missing an obstacle in the Spartan Race, which is already populated by people with washboard abs.
How: From a standing position, squat, place you hands on the ground, and “jump” your feet out into a pushup position. Perform a pushup and then jump your feet to your hands. Then jump as high as you can, throwing your hands over your head.
Prescription: 2 sets of 10 reps with 60 seconds rest between sets.
V-Sit Crunch
Why: For all of the abs-challenging reasons of a traditional crunch, but also because it keeps you from putting unnecessary torque on your neck and using momentum to complete the crunch. (That also makes it more difficult.)
How: Begin on your back with hands extended over your head. Lift your legs and crunch up at the same time, forming your body into the shape of a V. Exhale as you lift your legs, and crunch and inhale as you return to the starting position.
Prescription: 2 sets of 30 seconds with 60 seconds rest between sets.
Half Boat (aka Ardha Navasana)
Why: This yoga move is a variation of the V-sit crunch that targets the rectus abdomens.
How: From a sitting position, extend your arms out, palms facing each other. Extend and lift both legs, keeping them bent at the knees, with the insides of your feet touching. Extend your arms on either side of your legs. Use your abs to keep your back straight. Stay in this position for five deep breaths, roughly 10 seconds.
Prescription: 2 sets of 10 reps with 60 seconds rest between sets.
