Here's How to Decide What Size Stability Ball to Buy

Stability ball, exercise ball, Swiss ball, physio ball or giant beach ball? The stability ball has no shortage of nick names — and it's no surprise given the many hats this versatile tool can wear.

Exercise balls are large, inflatable balls used during workouts, physical therapy or as a replacement for your desk chair. They range in size and air pressure, depending on your height and how you want to use it. Before you pick just any stability ball, though, find the best size for your height to get your core firing.

Exercise balls are a great tool to build your balance, while targeting your abs, back and the rest of your core, according to the American Council on Exercise. The stability ball is often used in physical therapy, too, to help improve posture and preventing future injury.

It's also a useful piece of equipment to add to your home gym. Doing exercises on the ball adds an element of instability that requires more stabilization work from your core muscles. Dead bugs, planks and ab roll outs are just a few ab exercises that can be made more challenging (and effective) using a stability ball.

To find what size stability ball works best for you, it's crucial to take your height into account, according to the ACE. Exercise balls are sized in centimeters, and some companies even color code the balls for simpler designation. General size guidelines are accurate for most people, but you may find a larger or smaller ball more comfortable if you are near the top or bottom size limit.

Before you add to cart, reference these general recommendations:

If you're in the store, you can also check your seated height to determine the perfect ball size. When sitting on the ball, your hips and knees should form 90-degree angles, according to Harvard Health Publishing.

If you're buying on online, find the right size by squatting against a wall until your hips are parallel with the floor and your knees are at a 90-degree angle. Measure the distance between the floor and your hips and compare to ball measurements. Fully inflated, a 55-cm ball is 22 inches from the floor, and a 65-cm ball is 26 inches from the floor.

You should also take air pressure into consideration. Typically, the firmer the exercise ball, the more challenging the exercise. If you're buying a stability ball for rehabilitative purposes, though, you'll want to buy a ball according to your physical therapist's recommendation.

If you want to start integrating a physio ball into your core routine, try these Mayo Clinic-approved exercises.

1. Begin lying with your stomach on the ball, feet touching the floor.
2. Roll forward as you bring your hands to the ground and slowly walk your hands away from the ball until it supports your upper thighs.
3. Keep your shoulders over your hands and balance in this position, contracting your breath.
4. Hold here for three deep breaths, maintaining your balance.
5. Reverse the exercise to return to the starting position.
   

1. Lie on your back with your legs on either side of the ball about hip-width apart.
2. Contract your core and inner thighs to squeeze the ball with your legs. Keeping your lower back glued to the ground, lift the ball off the floor.
3. Hold the ball elevated for three deep breaths, keeping your core contracted.
4. On an exhale, lower the ball back down and return to the starting position.

1. Begin in a high plank with your hands on the ground, directly beneath your shoulders, knees and shins on the ball, hips level with the rest of your body.
2. Press your knees into the ball and tighten your core to roll the ball as you bring your knees toward your chest.
3. Hold here for three breaths.
4. Then, roll out to return to the starting position.