Boost their power even further—and target any trouble spot—with these fun (OK, challenging!) variations. To turn on those total-body trembles…Media Platforms Design Team Try: High or low plank Lie facedown with hands underneath your shoulders. Curl your toes under to grip the floor, then straighten your arms to lift your torso off the floor. Tighten your buns and abs. From a side view, there should be a diagonal line from the lobe of the ear to the shoulder, hip, and ankle. If this is painful on your wrists, transition to low plank. Simply bend the elbows and drop the forearms down to the ground, parallel to one another. Create a fist with your hands. Low plank is every bit as challenging for the core muscles as high plank, but it alleviates pressure from the wrists. Aim to hold for 30 to 60 seconds. (Get a flat belly in just ten minutes a day with our reader-tested exercise plan!) To set your abs on fire…Media Platforms Design Team Try: A stability ball variation Place a stability ball underneath your shins, then assume plank position. Lift your hips high towards the ceiling, causing the ball to roll toward the tongue of your shoes. Hold momentarily, then slowly, resisting gravity, return to start. To make it a little easier, bend your knees and tuck the ball in towards your tummy. Aim to do 2 sets of 12 reps. To challenge your obliques…Media Platforms Design Team Try: Side plank with a twist Assume plank position. Turn to one side and lift the top arm towards the ceiling, staggering your top leg in front of your bottom leg, coming into side plank. From there, sweep your top arm down and under your torso, as if weaving a piece of thread through the eye of a needle. Return to side plank. Aim to do 2 sets of 12 reps on each side. MORE: How To Turn Off Your Weight Gain Hormones To pull in your waist even more…Media Platforms Design Team Try: Plank with cross-body tap Assume high plank position. Lift the left foot slightly off the floor. Bring the left knee in to kiss the right triceps. Return to plank. Repeat, bringing the right knee to the left triceps. It’s OK if the knee doesn’t make it all the way in to touch the triceps! Just twist as deeply as you can, without lifting your hips to shorten the distance. Aim to do 2 sets of 12 reps on each side. To firm and flatten your low belly…Media Platforms Design Team Try: Plank to squat jump Assume plank position. Jump the feet in to position them in “sumo squat” position outside of the hands. Lift your torso up to “ready” stance. Place your hands back down on the ground, and jump back to plank position. Repeat! Aim to do 2 sets of 12 reps. To really target the triceps…Media Platforms Design Team Try: Triceps dip into an inverted plank Assume a triceps dip position, with your arms straight and low back against a chair. Perform one dip, bending your elbows deeply, allowing your back to slide down the front of the chair, as if you’re using the chair to scratch an itch. Extend the elbows back to the top of the dip, then hoist your hips as high as you can towards the ceiling to assume “inverted plank” position. Return to starting position. Repeat! Aim to do 2 sets of 12 reps. If this is too challenging, omit the dip and just go from starting position to an inverted plank. MORE: Resistant Starch May Be The Next Big Thing In Weight Loss. So Why Haven’t You Heard Of It? To up the toning power for your shoulders…Media Platforms Design Team Try: Push plank Assume high plank position. Bend your right elbow to drop your right forearm to the floor, then repeat with the left arm, coming into a low plank with forearms parallel. Now press back up to high plank: Press right palm into floor and straighten your arm, then repeat with the left. Continue, alternating your leading arm with each rep. To make it easier, drop your knees to the floor. Aim to do 2 sets of 12 reps. To super-tone your back…Media Platforms Design Team Try: Plank rows Assume high plank position with a dumbbell in each hand. Without shifting your hips, bring the right dumbbell to meet your ribcage. Return it to the floor to return to plank position, then repeat on the left side. That’s 1 rep. Aim to do 2 sets of 12 reps. To make it easier, drop your knees to the floor or do the move without dumbbells. To add a bonus challenge for the chest…Media Platforms Design Team Try: Push-up to plank shoulder tap Assume plank position, then walk palms out so they are slightly wider than shoulder width. Bend at the elbows to lower torso, bringing the tip of your nose down to touch the ground. Powerfully press back up to plank and tap your right hand to your left shoulder. That’s 1 rep. Repeat, tapping your left hand to your right shoulder on the next rep. Alternate which hand taps across to the other shoulder with each successive plank. Aim for 2 sets of 12 reps. To make it easier, drop your knees to the floor or omit the push-up and do plank taps only. To lift and burn your backside…Media Platforms Design Team Try: Plank hip abductor Assume plank position. Lift your right leg up and then out to the right, away from the body (as you would if forming a snow angel). Pulse right leg out to the right 3 times, then lower the leg back to starting position. Repeat on the left leg. That’s 1 rep. Aim for 2 sets of 12 reps. MORE: 5 Simple Moves To Prevent Back Pain To super-slim your hips and waist…Media Platforms Design Team Try: Plank hip dips Assume low plank position, forearms flat and parallel to one another. Roll and drop your hips to the right, touching the top of right thigh to the ground. Return to low plank. Repeat on the opposite side. That’s 1 rep. Aim for 2 sets of 12 reps. To make it easier, shorten the range. Just barely tilt each hip down, without dropping all the way to touch the floor. Make “micro-movements,” returning to low plank between each little shift. This option is especially useful if the full range of hip dips bothers your lower back. To tighten and tone your inner thighs…Media Platforms Design Team Try: Plank jumping jacks Assume plank position. Step both legs out wider, where there’s about a 2-foot gap between your legs. Perform plank jumping jacks by jumping your legs in together (where your feet touch) then jumping back to wide plank position. Repeat. Aim for 2 sets of 12 reps. To make it easier, skip the jump. Simply step your feet in, in, out, out; alternate which leg leads first. You can do this easier variation in high or low plank position.