You’ll start each week by simply holding a plank for 30 to 45 seconds. This is the classic isometric plank contractionyou’re familiar with—but remember the objective. You’re not t… See more

Start exploring how your core functions on each second day. One key function of your abs is to prevent your lower back and spine from arching, something known as spinal “extension.… See more

3 sets of 30 seconds Reach your arms out here, and place your palms flat on the floor. Keep the same basic plank cues in mind. It's okay to break before 30 seconds, if necessary.… See more

Another key core function: Your abs rotate your torso. They also help you resist all rotation (known as “anti-rotation”). Train both ideas every third day, building a stronger pl… See more