ISOMETRIC CORE EXERCISES: In these moves, you’ll hold a position for a period of time instead of contracting your muscles through a range of motion. Here are a couple of examples:

• Plank: Hold your body at the top of a push-up position for up to 60 seconds. This very effective exercise can be done in a variety of ways and modified for your fitness level.
• Bridge: Lie on your back with your knees bent and feet flat on the ground. Slowly raise your hips off the floor, tightening your abdominal muscles as you go and holding your hips as high up as you can for up to 60 seconds.

FITNESS BALL CORE EXERCISES: These are the large balls you see people sitting on at the gym. Though they may look like daycare toys, they provide serious benefits to grown-ups who sit or recline on them when doing core moves, like crunches. The instability forces your body to engage both large and small muscles. Here’s an example:

• Back Extension: Position your fitness ball under your hips and lower stomach. Walk your feet out until your knees are straight or close to it. Put your hands behind your head and lift your chest off the ball until your body makes a straight line. Repeat 10 to 12 times.

DYNAMIC CORE WORKOUTS: These workouts involve constant motion. Depending on the routine, you may move from side-to-side, up and down or in all different directions (sometimes while holding a weight, medicine ball or kettle bell). In other cases, you’ll simply be doing workout moves while fighting against instability—a wobbly surface or a balancing act on one leg, for example. These can really get your heart rate going, too. Here’s an example:

• Stand on the half-ball side of a Bosu^® ball with your feet hip-width apart and a slight bend in your knees and your arms extended up toward the ceiling. Drop your hips as though you’re lowering yourself into a chair until your thighs are close to parallel to the floor. Hold for a second, then return to your start position. Repeat 10 to 12 times.

Try to make time for three 10- to 15-minute core-strengthening sessions each week. It may be challenging at first, but stick with it. Once you begin strengthening your core, you will notice an improvement in the way you look, feel and move through your day.