URBNFit Quick-Pump Yoga Balance Ball

The workout bench is probably the most versatile piece of exercise equipment in any home gym, but a close second has got to be the balance ball. These giant inflatable spheres are also known as exercise balls, stability balls or Swiss balls depending on what they’re used for — and they have a laundry list of uses.

Workers with back pain can passively strengthen their abdominal muscles by sitting on them. Pregnant women can use them to adjust to added birth weight. Then there are the countless core-building workout routines that involve these simple balls.

So, how do you find the right balance ball, especially when they all look the same? The first question to answer is how will you be using it: Actively or passively?

Active use means you’ll be incorporating your ball in a lot of exercise routines. That calls for balls that have a little extra durability. Look for those that are rated for a higher weight capacity, and have anti-burst properties such as an internal “honeycomb” structure. This will prevent them from popping immediately if they roll over something sharp. You’ll also want them to have some kind of textured surface. They are called stability balls, after all, and you want to stay stable on them even if you’re sweating.

Whether you’re buying your ball for active or passive use, you’re going to want the right size. For workouts, you might actually want several. While there is a standard size based loosely on your height (see below), different exercises may require bigger or smaller balls. The smaller the ball, the harder it is to balance on, so you may want to size down for crunches or similar moves once you gain a little more core strength.

If you’re simply using the ball as a posture-enhancing chair, you only need one — but that one ball needs to suit your size. Make sure that when you sit on the ball, your legs are at the angle they would be when sitting normally (about 90 degrees). That means the ball should be bigger the taller you are. Here’s a general comparison chart:

• For those who are 5 feet 2 inches tall or shorter, use a 55-centimeter diameter ball.
• At 5 feet 3 inches to 5 feet 10 inches, use a 65-centimeter ball.
• At 5 feet 11 inches to 6 feet 4 inches, use a 75-centimeter ball.

If you’re outside that range, you can find even smaller or bigger balance balls. And of course, weight is a factor, too. Size up or down if you’re especially heavy or light for your frame.

Finally, make sure that you can get that ball into shape to begin with. Most balance balls come with a pump of some sort, and a removable stopper when it’s time to deflate them. If you’re taking it to work, a quick-working automatic pump might be worth a few extra bucks.

• If your balance ball is going to be a piece of exercise equipment, it goes without saying that you should use with care. Don’t wiggle around on it or try to test your balance until you’re comfortable on it.
• The dangers of passive use are less obvious, but they do exist. When you use a balance ball as a chair, you have to engage abdominal muscles you wouldn’t otherwise be using while seated. That can help improve your posture and slightly work your core, but make sure you don’t fall back into a slouch as you get more comfortable with your bouncy new seat.
• If you have balance issues to begin with, take it slow — and/or consider a “frame” for the ball that gives you some back support and keeps it from rolling away. The incremental benefits aren’t worth one bad fall.
• Bear in mind: Textured plastic surfaces can prevent you from slipping, but they can also attract a lot more lint and hair. If you have pets who shed, this is one area where you may want to “balance” your needs.