Get on your all fours, making sure your hands are directly under your shoulders and your knees are directly under your hips. Tuck your toes under, and lift your hips and butt up into the air, so your body forms an upside down “V.” Your head and neck should be in line with your back, not hanging down or rolled up. This is the starting position.Press down into your hands, and as you do, lift your chest and head up off the ground. Keep pressing until your arms are straight. You should now be in a “plank” position with your butt down, and only your toes, hands, and forearms touching the ground. Hold this position for as long as you can.Lower yourself back down to the starting position, and repeat the move for desired reps. Make sure to keep your abs tight throughout the entire exercise to really work those muscles! Remember to breathe while you’re doing this exercise; exhale as you press up into the plank position, and inhale as you lower back down.