For the past three weeks I’ve been doing intense hour-long training sessions at to repair my . I figured if it was good enough for Matt Damon and Drea de Matteo’s hot bods, it was good enough for me.

Deemsy has been taking me through my paces, helping me work my abs from a 360-degree perspective, not just from the belly. After our workouts I find that not only are my abs sore, but other muscles, including my lats and my hamstrings, are also getting worked.

The trainers at High Performance put a lot of focus on using your own body weight to build strength and endurance. I hadn’t done unassisted pull-ups for about 12 years. However, I’ve now built up enough strength to drag my body up to the bar at least a few times. It’s a good feeling.

Other core-stabilizing moves I’ve been doing (work up to 2-3 sets of 15 reps):

Hi-Lows: Starting from a plank position with your forearms on the floor, you first straighten one arm into a push-up position and then the other. Then you move back down to the low plank while trying to keep your hips stable. Once you’ve mastered this, you can upgrade the high position to a step.

Side Plank With Row: Calling on your , side planks are tough enough. But when you add a row to the workout, it throws off your balance, causing you to recruit those stabilizers in your core and back even more.

Plank With Row: Similar torture to above, but starting from a traditional horizontal plank. If you don’t have a friend to work out with who can hold your resistance band (a towel can work too), you can tie it around a piece of training equipment at the gym or a heavy table at home.

Push-up With Lateral Arm Raise: With weights in hand, start from a plank position and do a push-up. Then turn to your right side, raising your right hand above your head (with right arm straight), turning your body to the right as well. Return weight to the floor, do another push-up, and repeat on the left side.

Chest Press on Ball: With a weight in each hand, center your shoulder blades on top of a stability ball (bend knees at a right angle). You can press both arms up at once, meeting in the middle, or really challenge your balance by alternating pressing the right and left arms up individually.

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