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The best exercise balls for 2025 (and why you need one): Bosu, Theraband, Gaiam and more

Improve your balance and strengthen your core with the best stability balls and exercise balls on the market.

Exercise balls we tested precariously stacked.
We searched high and low to find the best exercise balls for newbies, fitness buffs, desk workers, children, pregnant women ... and you. (Libby Sentz/Yahoo)

One big ball could be just what you need to rock your core into shape. Experts say stability balls help prevent back pain and improve balance, making them a great choice for home workouts. You've probably seen them at the gym, at the physical therapist's office, in schools, in birthing centers and in Pilates studios. Perhaps there's one beneath your bottom right now.

Quick overview
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Certified personal trainer Derek Tresize points out, "You can do so many exercises on a ball; they're a great space- and time-saving option. … You can use them for a wide variety of exercises covering the entire body and really challenge your balance."

Some studies have shown that when core exercises are done on an exercise ball, they can improve stability and balance and are more effective at relieving low back pain than floor exercises alone. And if you are one of the up to 23% of adults with back pain — or don't wish to become one — this could be an effective tool to keep back pain at bay when used properly.

And let’s not forget the fun factor! "Along with the long list of therapeutic applications, the ball is an enjoyable way to exercise," says Despina Stamos, a Pilates instructor at SomafLux and former teacher of group physio ball classes. "The colorful balls inspire playfulness while being extremely effective."

Before filling my home with balls, I spoke with five experts across the fields of physical therapy, personal training, bodybuilding, Pilates and perinatal fitness. I then researched 33 balls of various types and sizes and narrowed my selection down to 23 to test in person. For good measure, I invited friends and family of various ages and sizes to give feedback. This resulted in these top picks.

Julie holding a ball with feet. The author with most of the balls tested.
Had a ball over here choosing the best exercise balls for you. (Libby Sentz/Yahoo)

Size options: 45 cm, 55 cm, 65 cm, 75 cm, 85 cm | Burst-resistant: Yes | Weight capacity: 1,000 lbs., static-tested to 600 lbs. | Colors: Up to 5, depending on size | Materials: PVC, phthalate-free, free of heavy metals, latex-free | Special features: Full-size exercise poster, 0.08-inch thick walls | Also included: Adapter for bike pump

This trusty Theraband Pro ball passed all our tests with flying colors. The durable, nontoxic 0.08-inch skin boasts roughly twice the thickness of most balls we tested. This also made it a bit tougher to pump initially, but an air compressor did the trick. Should it get punctured, it will kindly deflate slowly. The raised concentric rings help with grip, and the surface is just sticky enough to lessen slippage during exercise without feeling icky. The included full-size poster with photos of exercises provides immediate inspo. There are sizes to suit just about everyone, from 4'7" to 6'9" and up.

Both Pilates instructors we consulted are fans. Stamos says, "My preference is the TheraBand Pro Series ball as it’s constructed from nontoxic materials, is burst-proof and it’s made for physical therapists." Anna Clark, owner and master trainer at Nexa Studios in New York City, adds: "They have decades in the game and have built high-quality equipment people can trust." 

Indeed, TheraBand was started over 40 years ago by a pair of clinicians with the intention of helping patients recover and has become a go-to brand for many health and fitness pros.

Pros
  • Durable
  • Designed for physical therapy
  • Slow deflation
  • Full-size exercise poster
  • Thorough instructions
Cons
  • No pump included
$33 at Amazon
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$30 at Walmart

Size options: 55 cm, 65 cm | Burst-resistant: Yes | Weight capacity: 1,000 lbs. | Colors: 2 | Materials: PVC | Special features: Manual via QR code; one-year warranty Also included: Hand pump, two plugs

This tough Bosu ball is a great tool for intense workouts. During testing, it felt sturdy and very supportive and remained fully inflated. It also stayed cool to the touch, which was not one of our original criteria but totally is now. Ahhh. Despite the smooth skin, I found it to be no more slippery than the other top contenders when put to the sweat test — the subtle added texture at the top helps with grip. Plus, something about the old-school medicine ball look just inspires a Rocky-level workout. 

Made by personal trainers, this is the only U.S.-made ball we tested — or even found. It inflates easily with the hand pump and is burst-resistant up to 1,000 lbs. 

Pros
  • Very supportive
  • Firm
  • Feels nice against skin
  • Has a workout-ready vibe
Cons
  • No details on the phthalate levels, but Prop 65-compliant
  • Only two sizes
  • Only two colors
$30 at Bosu
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$30 at Target

Size options: 65 cm | Burst-resistant: Yes | Weight capacity: 1,000 lbs. | Colors: 1 | Materials: PVC, phthalate-free, free of heavy metals | Special features: Unique wavy and dotted texture Also included: Hand pump, two plugs, plug remover

Of the $20-and-under balls we considered, this Dick's Sporting Goods exclusive performed (and definitely looked) the best. It was simple to inflate, with clear instructions and helpful photos. It held its shape well and stayed fully inflated throughout testing, and the grabby texture helped to prevent slippage during exercise. Aesthetically, the warm, rosy-gray hue and wavy, textured design also caught the trained eye of my French artist friend who dropped by to give the balls a try.

While it's available in only one size, it was just right for my 5'9" frame and is well suited to those a few inches shorter or taller. 

Pros
  • Great price point
  • Performs well
  • Clear set-up instructions with photos
  • Looks expensive
Cons
  • Only one size available at this time
  • Only one color
$20 at Dick's Sporting Goods

Size options: 55 cm, 65 cm, 75 cm | Burst-resistant: Yes | Weight capacity: Static weight rated to 2,000 lbs. | Colors: Up to 3, depending on size | Materials: Non-phthalate PVC | Special features: Exercises are described in an included booklet, a free DVD featuring fitness educator Brook Benten and on the ball itself plus $1 app | Also included: Foot pump, 2 plugs, plug remover, bicycle pump adapter, measuring tape

Getting started is a breeze with this guy. It pumps up in minutes and displays the proper form for exercises everywhere, including right there on its face. My exercise partner Julie appreciated the rough grippy texture and thinner walls, "It has the best skin," she said, giving it a little squeeze. "The material is better for digging in and finding stability." I agree that it felt less likely to get away from me than the firmer balls when testing new positions.

Newbie ballers should heed the advice of Reginald Cociffi-Pointdujour, PT, DPT: "It is important to use any exercise tool safely and effectively. Always err on the side of caution if you are using any tool that requires you to have balance and trunk stability. If you are unsure about your own abilities, seek consultation with a physical or occupational therapist or with a trained and tested exercise professional."

Pros
  • Exercises shown in multiple places
  • Has some give, preferred by some users
  • Grippy texture
  • High weight rating
Cons
  • Not many customer reviews
  • Lesser-known brand
$30 at Amazon
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$30 at Walmart

Size options: 45 cm, 55 cm, 65 cm, 75 cm, 85 cm | Burst-resistant: Yes | Weight capacity: 2,200 lbs.; anti-burst to 330 lbs. | Colors: 6 | Materials: PVC, phthalate-free, BPA-free, free of harmful heavy metals | Also included: Foot pump, two plugs, plug remover, measuring tape

This nontoxic No. 1 bestseller has over 27,600 five-star fans at Amazon — and it lives up to the hype. It twins our winning pick, the TheraBand Pro, in design style, feel and sizing options. In a few ways, this Trideer excelled: It took under five minutes to inflate with the manual foot pump, offers more color options and boasts a higher weight capacity than the Theraband. It did not, however, include exercises or have the time-tested history of the TheraBand brand, and there was a minor visible manufacturing flaw (one of the raised circles was uneven around the plug), which puts the quality into question. Still, it has stayed inflated and held its shape quite well. Plus: Shoppers are loving it.

"This is a fabulous ball!" wrote one physical therapist in their Amazon review. "Very impressed with the quality, price and what's included. Nice to include the pump, though it is quite tedious (got a 'bonus leg workout' inflating it, LOL). Absolutely recommend this product."

Note: While it's priced similarly to the Theraband, we've seen it dramatically discounted during big sale events.

Pros
  • No. 1 bestseller at Amazon
  • Sturdy
  • Inflates quickly
  • Good variety of sizes and colors
Cons
  • Lesser-known brand
  • Minor design flaw spotted
  • No exercises included
$29 at Amazon

Size options: 55 cm, 65 cm, 75 cm. | Burst-resistant: Yes | Weight capacity: 440 lbs. | Colors: 3 | Materials: PVC, free from lead, cadmium and 10 harmful phthalates | Special features: Pregnancy guide, baby book | Also included: Hand pump, inflator, two plugs

This nontoxic, nonslip birthing ball is dedicated to the mamas for belly, birth and beyond. Its specs are similar to those of Amazon's No. 1 bestseller from Trideer, but it's newer, thicker and comes complete with a memory book, exercise guide and more at no extra cost.

Advanced doula Emily Wannenburg, CEO and founder of 4th Trimester Fitness Method, isn't picky about which exercise ball you choose during pregnancy, but she is such a believer in their benefits that she's created a whole training course on the subject. "In labor, the ball has many benefits," she says. "The ball rocks for back pain. Just sitting on the ball fires the deep core and pelvic stability muscles. In labor, hip circles and clocks are shown to reduce the perception of back labor between 6 and 8 cm. For postpartum, nothing beats small bounces on the ball holding a fussy newborn!" This last sentiment is echoed by Yahoo's Senior Health Writer, Laura Williams, who says she practically lived on a stability ball for the first few months after giving birth to her son — "It was either pacing for hours or bouncing on the stability ball — nothing else seemed to calm his colic," she says. 

Pros
  • Pregnancy-specific literature included
  • Soft, pastel colors
  • 10P-free (the best phthalate-free rating we found)
Cons
  • Not many customer reviews yet
$30 at Amazon

Size options: 55 cm, 65 cm, 75 cm, 85 cm, 95 cm | Burst-resistant: Yes | Weight capacity: 2,200 lbs. | Colors: 6 | Materials: PVC, BPA-free, latex-free, phthalate-free and free of heavy metals | Also included: Hand pump, inflator, two plugs

The tallest of the tall and the leggiest of the leggy will appreciate the supersize options available for this heavy-duty orb. The extra large sizes may also come in handy for those who are less flexible. The apparent durability is impressive. The maker notes, "It can withstand up to a 2 cm cut without explosively deflating." Reassuring!

Admittedly, after hours of trying with the hand pump, a bike pump and even an air compressor, I was unable to get it all the way to 95 cm, but it did surpass 85, which is the max for most other brands. 

Pros
  • Good for tall folks
  • Super-thick walls
  • High weight capacity
Cons
  • Included hand pump is insufficient; couldn't reach max size
$20 at Amazon

Size options: 40 cm, 55 cm, 70 cm, 85 cm | Burst resistant: No | Weight capacity: 270 lbs. (tested to 660 lbs.) | Colors: 3 | Materials: PVC, latex-free and phthalate-free, lead-free, BPA-free | Special features: Peanut-shaped | Also included: Extra plugs, pump adapter

This Italian-made inflatable looks, feels and smells like happy childhood memories (perhaps because it's made from the same thick, shiny vinyl as Rody the ride-on horse, who was born in the 1980s), but it's sized for grown-ups. It's an especially good choice for guided use with seniors and for people with balance issues who wish to engage in slow, gentle stretches and bodyweight-only core work. The vinyl is smooth and pleasant to the touch. 

While very thick, it's not anti-burst (there's no U.S. distributor for the burst-resistant version at the moment), so keep your exercise area free of sharp objects and inspect it for damage before every use. For those with balance issues, I'd recommend a spotter or placing it against a wall when first starting out.

"Throughout my career, I have worked with elderly individuals who benefited from balance and stability training," Stamos says. "A favorite beginner exercise for grounding is having the student sit on the ball with feet planted on the floor while I gently push on the ball from different directions. My light pressure on the ball challenges the client to maintain their stability against pressure, which activates core and deeper muscles that can be overridden by larger muscle groups in most traditional exercise modalities. I also love the relaxation that laying the torso over the ball produces, both prone and supine."

Note: I tested the massive red version, but this 70 cm blue or the 55 cm yellow will be much more manageable for most adults. 

Pros
  • More stable than a ball
  • Thick
  • Innovative company
  • More pleasant smell than others
Cons
  • Not burst-resistant
  • No instructions included
  • No pump included
$90 at Amazon

Size options: 65 cm diameter. | Burst-resistant: Yes. | Weight capacity: 350 lbs. | Colors: 8 | Materials: Latex-free, "phthalate-compliant" | Special features: QR code with manual, workout videos, downloadable wall charts and more; one-year warranty | Also included: Hand pump

The made-in-the-USA Bosu outshines its half-ball competition when it comes to functionality and quality. Sure, there are other lighter halfsies (this one is 15 lbs) and more affordable options out there, including two that we tried and liked (see "Other products we tested," below). Still, Bosu claims the crown. It's easy to use, durable and reliable — it held air and stayed put during our workouts. Plus, our experts are into it:

"I like Bosu balls a lot for hip and core work," Tresize tells Yahoo Life. "Any exercise performed while standing on a Bosu adds a big balance challenge, and I enjoy crunches and hip thrusts on it as well."

Stamos seconds that: "Bosu balls are fantastic for proprioception and balance. Just standing on them activates muscles to keep you from falling off. After mastering standing on two legs, lifting one leg and balancing is simple but difficult and very effective in energizing the core reflexes. Bird dog [exercise] on the Bosu is excellent for core stability as well as ab work with the half ball under the torso."

Pros
  • Solid
  • Versatile
  • Made in the U.S.
Cons
  • Heavier than others we tested
  • Expensive
$157 at Amazon
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$190 at Bosu

Size options: 9 inches. | Burst-resistant: Yes | Weight capacity: 264 lbs. | Colors: 6 | Materials: PVC | Special features: Honeycomb anti-burst material, 9 exercises included | Also included: Straw for inflation, plug

This high-quality, nontoxic 9-incher is our top pick of the minis for core work, pelvic floor work, barre exercises, stretches and restorative poses. It inflates in seconds, holds air well, feels durable and has just the right amount of stickiness. In the roomful of balls, this is the only one that my friend and workout buddy Julie wanted to sneak out with: "This I could use, and it wouldn't take too much space."

Clark says mini balls are a great add: "These much smaller, even more affordable little balls have more application as a tool to pull everything into alignment when you place them in the hands or feet to 'hug the midline' of the body. In the feet or thighs they act much like a ThighMaster while also lining up the leg bones and helping the tracking of the knees during various exercises." 

Stamos chimes in: "Another great use is to place the ball under the pelvis to relax into proper hip alignment. Once aligned well, single and double leg extensions are a wonderful way to strengthen the core."

Pros
  • Durable
  • Affordable
  • Space-saving
  • Quick inflation
  • Travel-ready
  • No odor
Cons
  • Exercise sheet could be more thorough.
  • Some Amazon reviewers found sizing to be inconsistent.
$10 at Amazon

Size options: 65 cm. | Burst-resistant: Yes. | Weight capacity: 265 lbs. | Colors: 2 | Materials: Cover: Natural cork with leather trim (faux leather available on request); layer: polyester and nylon; inner ball: PVC | Special features: Cork cover, lovely stitching, leather handle. | Also included: Plastic hand pump wrapped in leather.

Want to go all out? This made-in-Poland ball is a stunner with a gold-paint-flecked cork cover that's stitched shut and finished with a fine leather trim and handle (or faux leather, if preferred). In fact, this sphere can do triple duty — as workout hero, bonus seating and art piece. The cover, also available with silver accents, is eco-friendly, durable, nonslip and ready to use without a mat. (Naked vinyl balls don't do well on wood floors or when touching painted surfaces.) 

If this isn't indulgent enough, take a gander at what else this purveyor of handcrafted fitness equipment has to offer — namely, the super-decadent (and even pricier) original Mesna Premium Leather fitness ball

Do you need one of these? Probably not. But it's a mighty fine design upgrade for the person who has it all.

Pros
  • Gorgeous
  • Cover made with natural materials
  • No mat needed
  • Handle
Cons
  • Overpriced
  • No instructions included
  • Lead time of 3 to 4 weeks
$520 at Pent Fitness

Size options: Fits 5' to 5'11", optional extenders available. | Burst-resistant: Yes. | Weight capacity: 300 lbs. | Colors: 1 | Materials: Nylon, steel and PVC (latex-free, 7P-free) | Special features: Casters that lock, removable exercise ball, downloadable chair exercise guide | Also included: Pump, plugs, clear instructions

I'm a wiggly one at work. I've had my share of hip surgeries (four, so far) and spine issues, so being stuck in an office chair all day is frustrating, confining and deeply uncomfortable to me. But Cociffi-Pointdujour warns against substituting an exercise ball alone for your office chair: "It is not a safe alternative to a normal chair and is likely not more useful than regular exercise to achieve improved trunk stability." I'm finding this roll-y ball chair from Gaiam to be a nice hybrid option for part-time seating. It is superior to a ball alone, thanks to wheels that can lock, and when removed from its chassis it's great for midday stretches. There's even a swivel base option for $21 extra.

Unfortunately, what appears to be some semblance of lumbar support is actually not. It's intended only as support to grab onto during stretches, according to Gaiam. (Note: I did try slipping a semi-deflated miniball back there, and it felt nice.) Hopefully lumbar support will be an option in a future model. 

The ball itself is a sister of the one that Clark recommends: "Gaiam has been making bodyweight and calisthenic equipment for decades before the rest, and I will stay loyal to those that have been in the know the longest. They offer great, high-quality equipment across the board."

Pros
  • Sturdy base
  • Locking wheels
  • Simple to put together
  • Great for impromptu exercises
  • Ball easily used separately
Cons
  • No lumbar support
  • More expensive than the others tested
$100 at Amazon
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$100 at Gaiam

Size options: 45 cm. | Age recommendation: 5 to 8. | Burst-resistant: Yes. | Weight capacity: 200 lbs. | Colors: 2 | Materials: PVC that's 8P-free and free of heavy metals | Special features: Peanut shape | Also included: Pump

Kids delight at the sight of this bouncy peanut. It carries an age recommendation of 5-7, but I tested it with four kids (ages 5, 7, 8 and 10) who found countless uses, including rocking, rolling, bouncing, squeezing, superhero-ing, lifting, tossing and eventually a bit of sitting. An excellent tool for creative play and gross motor skills, coordination, balance, strength and core stability. Note: Do not stand or kneel on this or any ball.

As a former preschool teacher and creative movement instructor, I can attest that most children will dive headlong onto a big round ball — and go flying. This fun-size option is safer and less stress-inducing for any adults present. My young testers unanimously preferred it to the ball seats with stabilizing feet. 

Pros
  • Great shape for open-ended play
  • Cradles the body
  • More stability than ball
  • Can serve as a bouncy chair
Cons
  • Only 2 color options (kids may want more)
  • Only one size
$19 at Amazon
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$20 at Gaiam

Standard exercise balls, also called stability or physio balls, are used for workouts, stretching or physical therapy. They usually cost about $30 or so and quality may vary, as can the texture, design, thickness and type of the material.

While using them as office chair alternatives has become trendy, opinions are divided on their effectiveness. Some manufacturers advise against it due to safety concerns, such as the ball rolling or slipping and causing users to fall. Placing the ball on a mat or having a wall behind you can help. We set out to find a safe ball chair that would remain stable throughout a workday.

Half balls, with a rigid base and inflated top, are ideal for balance exercises and adding variety to workouts. "These are excellent tools for balance training and adding variety to an old-school workout," Clark says. "They can definitely spice up your fitness routine and add more layers of complexity to the otherwise standard exercises."

Core balls, or 9-inch mini balls, are used in Pilates and barre for targeting the deep core muscles, glutes and inner thighs.

Lastly, kids' balls deserve mention since these were originally created for them in 1963 by Aquilino Cosani for newborn therapy, as Pilates expert Stamos explained to us. Who knew?

Kids playing with peanut-shaped Gaiam.
Go nuts! A blurry, behind-the-scenes peek at what ensued when I handed the peanut-shaped Gaiam to kids ages 5 to 10. (Libby Sentz/Yahoo)
  • Fitness goals Whether you're shooting for a cinched waist, a stronger core, sculpted muscles, increased flexibility, rehabilitation, strength through pregnancy or better balance, there is a ball on this page that is suited to help you get there. It's all in how you use them.
    Clark says: "I am the biggest fan of the large physio balls because they can be used for so many exercises and target every muscle group on your list."

  • Type of workout If you are going for a sweaty, hard-core workout, you want a good weight rating and a nonslip surface. For stretching, you'll want solid support. If it's versatility you crave, something like a Bosu might be a good fit. If you are doing floor or barre work with isolations or if your space is limited, a mini ball is a great choice.
    While many ball makers advise against using these balls with weights, perhaps for liability reasons, personal trainer Tresize has found success incorporating them. "Depending on the exercise, using a ball rather than a stable surface such as a bench or the floor forces you to carefully control your movement and balance and weights you are using." (Read warnings in your ball's manual carefully and make sure the ball is anti-burst, properly inflated, free from damage and has a very high weight cap before considering adding extra weight.)

  • Size Each brand has its own sizing chart, which generally look something like this: 45 cm for 5' and under, 55 cm for 5'1" to 5'6", 65 cm for 5'7 to 6'1", and 75 cm for 6'2" and above. If you have extra-long legs for your height, you may want to size up.
    "There's a little wiggle room," Tresize says, "but generally I gauge it by if you can sit upright comfortably on the ball as if it were a chair. If it feels awkwardly high or low, try resizing."

  • Weight capacity Check the numbers before you pounce or bounce. Some exercise balls are rated for a very high capacity, which is great, but that doesn't mean you should thrust yourself upon it or add extra weight. Also, note that ball seats with weight limits of around 250 or 300 pounds are for sitting only. Misusing a ball chair may cause it to burst.

  • Durability/materials Stamos advises shoppers to look for "nontoxic materials ... and to make sure it's burst-proof." The ball should be thick enough that it is resistant to puncture and tears, which is why most balls are made with PVC (polyvinyl chloride) because it is flexible yet strong. Studies continue to show PVC to be toxic and environmentally damaging, so look for PVC that is phthalate-free and free of heavy metals. You also want a slow-deflate ball, not something that will immediately collapse if punctured. Some exercise balls carry a California Proposition 65 warning, which is given to products that contain or will expose a consumer to chemicals known to the state of California to cause cancer and birth defects or other reproductive harm if above certain threshold levels. We strived to find picks that do not carry the warning.

  • Experience level According to Cociffi-Pointdujour, exercise balls can be used for a variety of exercises — lying down, sitting or standing — that are aimed at increasing levels of trunk stability and balance. He recommends supervision by an exercise professional or a physical therapist, especially for those unfamiliar with the movements or those with poor balance. Holding on to a stable surface, such as a table, may be necessary for added stability.
    Of course, there's always one key risk, says Wannenburg: "Falling off the ball! People with severe balance challenges may not be suited to sit on a ball without extra stability support." She recommends placing the ball against two walls (in a corner) for added stability or using the ball to assist with squats by placing it behind the back.

  • Budget & brand reputation There are many good-quality exercise balls from trusted brands in the $30 to $40 range. As you get into more specialized designs and materials (chairs and fancy covers), prices go up.

Julie testing balls
My workout buddy Julie tests out the UrbnFit, Bosu and Calia options. (Libby Sentz/Yahoo)

After consulting with experts, including a bodybuilder-trainer, physical therapist, two Pilates instructors and a doula, I reviewed studies and customer reviews, finally selecting 23 balls, half-balls and children's balls to review. For kids, I relied on my experience as a parent and children's yoga teacher, opting for peanut-style and footed balls over larger ones for better control.

Over the course of 2 to 3 weeks, I put each ball through a series of tests. I aired them out to gauge their PVC smell, inflated them and reinflated them to test how easy they were to inflate, how stable they were when used and how well they held their air.

I tested large balls with wall squats, crunches, hamstring curls and planks, assessing texture, support and durability. For half-balls, I tried crunches, bird dogs, bridges, mountain climbers and burpees to check for slippage and quality. The children’s balls were tested by actual kids.

Refer to the size chart from each brand. Or if feeling it out in person, Wannenburg says, "When sitting on the ball the hips should be at the same level or higher than the knees."

Stamos says, "In Pilates, we use physio balls to target the core muscles, including the abdominals, obliques and lower back. The unstable surface of the ball challenges the core to maintain stability, which increases muscle engagement."

Speak with your doctor if you have acute or chronic back pain before starting any new exercise program. But exercise balls are often used for physical therapy and building core strength to support the back.

Clark says: "The physio ball can be helpful in building the strength needed to support the structure of the spinal column and create space through the joints, alleviating pressure and pain. I would, though, recommend getting a knowledgeable coach when starting out so you learn to use the ball correctly for your particular condition."

"Many!" says Tresize. "A few good ones are push-ups with your feet on the ball, plank with your elbows on the ball ... ball crunches, back supported wall squats and ball hip thrusts."

Many makers include exercise suggestions along with the ball or on their website.

Almost every ball we tested (aside from our top TheraBand pick and the Gymnic balls) included a hand pump, and a few had adapters for bike pumps. Instructions for most advise against using an air compressor, but a couple of the thicker balls needed one to get started. Most say to initially lay the balls flat for either several hours or a day. Then pump only to 50% to 80% of the full size (depending on the instructions) in fair temperatures. Wait 24 hours before topping them off. Two simple ways to measure for inflation: (1) Mark a spot on the wall with the full measurement and pump to that height, or (2) place two objects the indicated distance apart and pump until the ball fills the space.

For best results, keep vinyl balls away from wood surfaces (the materials don't interact well), sharp objects (including animals with claws) and painted items (walls). These are meant to be used indoors and out of the sun. Most can be wiped clean with soap and water.

Author with a pile of exercise balls
Don't try this at home. A clownish avalanche ensued seconds after attempting a timed selfie. (Libby Sentz/Yahoo)

Frankly, any of the vetted exercise balls that made it to the testing stage will do the trick, so feel free to shop these honorable mentions below. Each held its shape during testing and was supportive enough for workouts. For example, the Gaiam (Clark's pick), UrbnFit and Signature Fitness BalanceFrom (the lowest priced at $13) have a design that's similar to the winning TheraBand Pro and Trideer, with concentric circles and grippy texture. They just weren't quite as high-quality. The Gymnic Plus BRQ was plenty thick, firm and of good quality, but I could not get it pumped to its full listed size.

For the half-dome trainers, we tested a solid alternative from Dick's Sporting Goods brand Calia that in some ways topped the winning Bosu (the clever handle indentations on bottom and the light weight are nice for burpees and make it easy to move; plus it features options to hook on straps or bands). It also seems to be perpetually on sale. But ultimately it wasn't selected because it slips without a mat during exercises such as single leg glute bridges and sit-ups. A decent budget option from UrbnFit did not slip, but the narrower frame might limit it to those with more petite feet.

For seating, I also tested the Gaiam Classic Balance Ball Chair and the Vivora Luno Sitting Ball. The Gaiam Classic is $30 cheaper than the winning Gaiam Ultimate but was a bit more cumbersome and less sleek, and the ball trickier to separate from the base. Vivora's Luno ball features a lovely felt cover, handy handle and nonslip base, but the ball wouldn't behave. It rolled to its side when inflated to the size of the cover.

There were other shapes and sizes too: All three 9-inch mini balls tested well. I liked the grippiness of the Theraband Mini Ball and the ProBody Pilates Exercise Ball — but the selected Trideer offers superior support and a better feel. And while the footed Trideer Balance Ball was cute and fine for children's seating, the kids I tested it with were far more interested in the peanut style from Gaiam. For something a little different, I also tried the nice large, nubby, Italian-made Gymnic Therasensory Ball for massage but ultimately left it off the list because it was not burst-resistant. Still, it's a nice choice for gentle use by those with sensory needs.