By Nora Tobin for Shape.com


Just as a well-built house starts with a solid foundation, a truly fit body starts with a strong core. Whether you're hoisting weights, chasing balls, or just sitting up straight at a desk, your core muscles help you do it better, with less effort and less risk of injury.


When performed properly, most compound exercises such as squats, deadlifts, and rows require your core to engage, so it's not always necessary to devote an entire workout to training those muscles. But since when was only doing what's truly "necessary" the fastest way to reach your goals? Dedicate just one hour a week to training your core and you'll notice flatter, more defined abs, better posture, and improved sports performance (thanks to more support from your deepest abdominal muscles) in less time.


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How It Works: Once a week, perform 1 set of each exercise in order. After the final exercise, rest as needed, and repeat the full circuit 2 more times. If you want an extra dose of calorie-burn, do 15 minutes of jump rope intervals (20 seconds on, 10 seconds off) immediately after this workout.


You'll need: A mat (optional).



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  • Side Plank Raises


    Reps: 15 per side Lie on right side with knees straight. Prop upper body up on right elbow and forearm. Brace core and raise hips until body forms a straight line from ankles to shoulders. Lift and lower hips 1 inch in each direction, keeping glutes and core engaged the entire time. Do 15 reps, and then turn around to repeat on the other side.




  • Rocking Plank


    1 minute Come into a modified plank with elbows directly under shoulders, feet hip-width apart. Keeping hips level, begin to rock forward by pulling elbows down towards feet, not simply pushing forward and back with your toes. Squeeze glutes and brace core the entire time. Continue shifting forward and back for 1 minute.




  • Straight-Arm Plank With Twist


    Reps: 10 per side Come into a straight-arm plank with wrists directly below shoulders and feet slightly wider than hip width. Keeping hips stable, thread left hand under right arm. Return to center and continue twisting left to open chest toward the side wall. Finish with left arm directly above shoulder. Return to center and repeat. Do 10 reps on each side.




  • V-Up With Opposite Arm Reach


    Reps: 10 per side Lie faceup with arms by your sides. Lift shoulder blades off the ground as you lift left leg up, reaching right hand to the outside of left leg. Slowly lower leg and roll back down to start. Repeat movement on the other side, reaching left hand to the outside of right leg. Continue alternating at a quick but controlled pace. Do 10 reps on each side.




  • Static Plank


    1 minute Come into a plank position with feet hip-width apart and elbows directly under shoulders. Brace core by contracting abs as if you were about to be punched in the gut. Keep spine neutral and legs and glutes engaged the entire time. Hold for 1 minute.




  • Figure 8'S


    Reps: 30 per side Come into a seated position with knees bent and feet flat on the floor, hip-width apart. Lift your chest as you hinge back at your hips. Brace core and keep abs engaged during the entire movement. Clasp hands and straighten arms directly out from shoulders. Draw an '8' with arms directly in front of chest. Do 30 reps one direction, and then repeat going in the opposite direction.