How to measure a fitness ball

Kristin McGee is a certified personal trainer and currently teaches yoga and meditation for Peloton. She is also certified in Pilates and by the National Association of Sports Medicine.

How to measure a fitness ball

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Exercise balls, or stability balls, are useful for workouts or for use as a chair. They add a core stability challenge to just about any exercise. It is essential to get the correct exercise ball size for your body and purpose. There are ways to help make sure that the size and firmness of your exercise ball will provide an optimal workout.

Exercise Ball Size Chart

You will want to choose a ball size that is proportional to your height. The rule of thumb is that you want to be able to sit on your ball with your legs at a 90-degree angle or slightly more, but not less. Your thighs should be parallel to the ground or angled slightly down. With your feet flat on the floor and spine straight (not leaning forward, backward, or sideways), your knees should be even with or slightly lower than your hips.

Height Exercise Ball Size
Under 5′ 45 cm
Between 5’ and 5’5” 55 cm
Between 5’6 and 6’2” 65 cm
Over 6’2” 75 cm

Use this guide from the American Council on Exercise

Getting the right exercise ball for your weight also matters. If you are heavy for your height, you may need a larger ball to keep your knees and legs at the correct angle. Look for a durable, thick ball with high burst resistance. Check the weight rating on the ball before buying.

Exercise Ball Inflation

For most exercise purposes, you want to have a little give on the surface of the ball. When you sit on the exercise ball, your body weight should create a little seat. This provides more stability, but more importantly, it allows you to sit evenly on the ball. It is essential to exercise with good alignment.

The more inflated the ball is, the more difficult it will be to balance on it, whether sitting or in another position. So inflation is a matter of preference, but avoid inflating the ball so far that it is at risk of bursting. Your ball may require reinflation from time to time. Most are sold with a small pump for this purpose.

What to Do with Your Exercise Ball

You can use an exercise ball for many things. They are highly versatile as an inexpensive, easy-to-use home workout tool. Exercise balls are particularly beneficial for improving core strength and stability. Here are a few ideas:

More Exercise Info:

Effectively performing exercise ball activities requires careful selection of the right exercise ball size. Because personal consultations are not always possible, physical therapists, exercise trainers, and other professionals have constructed several guidelines to use when selecting the proper exercise ball size.

When sitting upright on an exercise ball:

  • Feet should be flat on the floor – with an even weight distribution.
  • Knees should be level or slightly lower than the pelvis – creating an angle of 90 degrees or slightly greater at the hips and knees (thighs parallel to ground or pointing down slightly).
  • Pelvis, shoulders, and ears should be in a vertical line – the body should not be leaning in any direction as a counterbalance. Bouncing up and down lightly will usually produce this alignment.

Exercise balls generally come in five different diametrical sizes. Each of these sizes is accordingly used for people of differing body compositions.

It is important to note that height alone is not the only factor in determining ball size. Because the exercise balls are flexible and offer resistance, weight is also an important factor.

A general guideline for height correspondence to diameter of exercise ball is as follows (this is assuming average body weight is proportional to height):

Exercise ball diameter Person’s height
45 cm 5′ and under
55 cm 5’1″– 5’8″
65 cm 5’9″– 6’2″
75 cm 6’3″– 6’7″
85 cm 6’8″ and taller

If body weight to height is larger than the average proportion, sitting on the exercise ball will compress it down more, so individuals usually should try using the next larger exercise ball size in order to maintain the 90-degree rule. Another factor to keep in mind is that most exercise ball sizes have some adjustability to them. If the angles at the hips and knees are much greater than 90 degrees, some air can be released to compensate and vice versa.

Bear in mind, releasing air from the exercise ball will cause it to lose air pressure. As the ball flattens out, this will actually make it more stable, as it has a larger contact area with the resisting surface and the body. This means that stabilizing and balancing exercises will become easier and will lose some effectiveness.

Exercise balls also lose pressure because of stretching from regular usage. Therefore, as the ball ages, it may require further inflation. On the other hand, adding excessive air to the exercise ball will increase the difficulty of balancing and stabilizing, as the contact area decreases.

Do you use an exercise ball?

Are you sure your exercise ball is the right size?

This short video shows you how to fit the correct exercise ball size for your body.

Knowing the correct exercise ball size helps you get the most benefit from your core exercises and minimize the strain on your lower back, pelvis and hips.

Video duration: 3 minutes

Suitability: General

Please scroll down below this video for written guidelines and a checklist for choosing the right exercise ball size.

Benefits of using the Correct Exercise Ball Size

There are 2 main benefits from using the right size ball for your exercises:

1. Increased effectiveness of seated core abdominal exercises
2. Reduced strain on the lower back, hips and pelvis

Problems with Recommended Exercise Ball Size Height Guides

It’s common practice to use a height guide to choose the right size ball.

While this is OK as a general guide this doesn’t work for all women for all core exercises.

The size of the exercise ball is usually printed on the ball in centimetres. Most exercise balls have the ball size printed on them, usually 45 cm, 55 cm, 65 cm and 75 cm.

Problems using the recommended ball size height guides are created by:

  • Age of the ball
  • Level of inflation
  • Individual differences – body weight, leg length, coexisting back or pelvic pain conditions
  • Ball manufacturing differences- materials used, pressure within the ball, sizing differences one manufacturer to the next

Standard Recommended Ball Size Height Chart

Here are the standard ball size height recommendations. Use these as a general guide only – you really need to sit on the exercise ball to assess its suitability for your body.

Most exercise balls have the ball size printed on them, usually 45 cm, 55 cm, 65 cm, 75 cm

Height and ball size (general recommendations). Ideally sit on the ball to check the right fit before buying.

Height Ball Circumference

Less than 4’8″ = 45 cm ball

4’8” to 5’3″ = 55 cm ball

5’4” to 5’1″ = 65 cm ball

5’10 to 6’4″ = 75 cm ball

Checklist to ensure Correct Exercise Ball Size

Sit on the ball side on to a mirror and check the following:

1. Is the ball manufactured from quality anti burst material?
2. Is the ball sufficiently inflated so that it feels reasonable firm to touch?
3. Can you rest both of your feet on the ground while sitting on top of the ball?
4. Are your hips positioned slightly higher than your knees when viewed from the side?

Troubleshooting Ball Some Common Ball Size Problems

Some of the most commonly experienced ball size problems stem from:

  • Leg length differences– women with long legs will require a larger ball than a woman of the same height with short legs
  • Body weight– heavier body weight tends to compress the ball more than lighter body weight
  • Lower back , hip and/or pelvic joint dysfunction– positioning the hips well above the knees can relieve pressure from these joints

Key Points for Fitting the Correct Size Exercise Ball

  • Getting the right size exercise ball promotes the activity of your deep core abdominal muscles and reduces pressure on the joints of the lower back, pelvis and hips.
  • Use the recommended ball size height guide as a general guide only. Differences in ball manufacture and individual body shapes and sizes mean that these size guides don’t necessarily apply for seated ball exercises.
  • The best way to know if your exercise ball size is right for your seated core exercises is to sit on your ball and view it from the side in a mirror.

Next: Exercise ball video demonstrating seated abdominal core exercises

We welcome your comments below

Please read our disclaimer regarding this information.

Do you use an exercise ball?

Are you sure your exercise ball is the right size?

This short video shows you how to fit the correct exercise ball size for your body.

Knowing the correct exercise ball size helps you get the most benefit from your core exercises and minimize the strain on your lower back, pelvis and hips.

Video duration: 3 minutes

Suitability: General

Please scroll down below this video for written guidelines and a checklist for choosing the right exercise ball size.

Benefits of using the Correct Exercise Ball Size

There are 2 main benefits from using the right size ball for your exercises:

1. Increased effectiveness of seated core abdominal exercises
2. Reduced strain on the lower back, hips and pelvis

Problems with Recommended Exercise Ball Size Height Guides

It’s common practice to use a height guide to choose the right size ball.

While this is OK as a general guide this doesn’t work for all women for all core exercises.

The size of the exercise ball is usually printed on the ball in centimetres. Most exercise balls have the ball size printed on them, usually 45 cm, 55 cm, 65 cm and 75 cm.

Problems using the recommended ball size height guides are created by:

  • Age of the ball
  • Level of inflation
  • Individual differences – body weight, leg length, coexisting back or pelvic pain conditions
  • Ball manufacturing differences- materials used, pressure within the ball, sizing differences one manufacturer to the next

Standard Recommended Ball Size Height Chart

Here are the standard ball size height recommendations. Use these as a general guide only – you really need to sit on the exercise ball to assess its suitability for your body.

Most exercise balls have the ball size printed on them, usually 45 cm, 55 cm, 65 cm, 75 cm

Height and ball size (general recommendations). Ideally sit on the ball to check the right fit before buying.

Height Ball Circumference

Less than 4’8″ = 45 cm ball

4’8” to 5’3″ = 55 cm ball

5’4” to 5’1″ = 65 cm ball

5’10 to 6’4″ = 75 cm ball

Checklist to ensure Correct Exercise Ball Size

Sit on the ball side on to a mirror and check the following:

1. Is the ball manufactured from quality anti burst material?
2. Is the ball sufficiently inflated so that it feels reasonable firm to touch?
3. Can you rest both of your feet on the ground while sitting on top of the ball?
4. Are your hips positioned slightly higher than your knees when viewed from the side?

Troubleshooting Ball Some Common Ball Size Problems

Some of the most commonly experienced ball size problems stem from:

  • Leg length differences– women with long legs will require a larger ball than a woman of the same height with short legs
  • Body weight– heavier body weight tends to compress the ball more than lighter body weight
  • Lower back , hip and/or pelvic joint dysfunction– positioning the hips well above the knees can relieve pressure from these joints

Key Points for Fitting the Correct Size Exercise Ball

  • Getting the right size exercise ball promotes the activity of your deep core abdominal muscles and reduces pressure on the joints of the lower back, pelvis and hips.
  • Use the recommended ball size height guide as a general guide only. Differences in ball manufacture and individual body shapes and sizes mean that these size guides don’t necessarily apply for seated ball exercises.
  • The best way to know if your exercise ball size is right for your seated core exercises is to sit on your ball and view it from the side in a mirror.

Next: Exercise ball video demonstrating seated abdominal core exercises

We welcome your comments below

Please read our disclaimer regarding this information.

CHOOSE THE CORRECT EXERCISE BALL SIZE

Please read all the information carefully before selecting a ball. A few minutes spent reading now might save you the time and money of having to return a wrong-sized ball later…and pay to have another shipped!

The general rule for choosing the correct exercise ball size for core (abs/low back) exercises is to have your knees and hips bent to 90 degrees (thighs parallel to floor) when sitting on the ball. This is the minimum ball size–some people prefer a larger ball, where hips are higher than knees. Don’t go by photos of models sitting on balls. Typically they sit on a ball much larger than they would train on as it photographs better.

Consider how you will use the ball and your body characteristics (see below). Also, keep in mind that if you are a novice exerciser and/or have poor balance, a larger ball will provide more stability and support, thus making exercising easier (muscles won’t work as hard).

To avoid being disappointed that your ball is smaller than you expected, test out the ball size before ordering. Most people underinflate a ball because it is so firm (like a rock) inflated to its maximum diameter. To see if a 55cm ball is right for you, place a mark on a wall about 20 inches high (16 in. for a 45cm ball), and squat next to it. Consider that you will sink down a few inches (depending on your weight and amount of inflation). This is approximately how tall the ball will be when sitting on it. Get a larger size if you don’t like this height!

GENERAL GUIDELINES:

Your Height Ball Size (max. height/diameter)

less than 5′ 0″ 45 cm (18 in.)

5′ 0″ to 5′ 5″ 55 cm (22 in.) [purchase]

5′ 6″- 6′ 1″ 65 cm (26 in.) [purchase]

6′ 2″ – 6′ 8″ 75 cm (30 in.) [purchase]

6′ 9″ and up 85 cm (34 in.)

Note: Only the Fitness Ball is available in 45cm & 85cm sizes

A LARGER BALL MAY BE NEEDED IF YOU:

  • have long legs for your height
  • have back problems
  • are using the ball for stretching, yoga, or as an office chair

An exercise ball is VERY firm at its maximum diameter. If in doubt, go with a larger ball (you don’t have to inflate it to the maximum diameter). This means getting a ball one size larger than the chart suggests if you are near the upper range.

Using an Exercise Ball as an Office Chair

How to measure a fitness ball

How to measure a fitness ball

First things first: an exercise ball = physio ball = stability ball = fitness ball. Got that? Good.

“A stability ball is a great way to amp up exercises for the entire body: upper, lower, and core.”

No matter what you call it, this inflatable sphere is an essential—and versatile!—piece of workout equipment. “Not only is it applicable to people of all levels—from beginners to advanced—but a stability ball is a great way to amp up exercises for the entire body: upper, lower, and core” says Laura Miranda, DPT, CSCS, New York City-based personal trainer and fitness expert. “It can function as a form of resistance, albeit light, much like a dumbbell, kettlebell, or barbell, or it can work as a platform on top of which you perform exercises,”

And, in case you’re still not totally sold (TBH, why tho?), exercise balls are also relatively inexpensive, ranging from $15–$30 on average, making them one piece of home gym equipment that’s definitely worth the investment.

Okay, what size exercise ball should I by?

There’s no one-size-fits-all situation with exercise balls. Instead, finding the right one for you depends on a few factors (more on that in a minute), but in general, you can use this chart below as a guide.

  • Height: Under 4’8” » Ball size: 45 cm/18”
  • Height: 4’8 to 5’3” » Ball size: 55 cm/22”
  • Height: 5’4” to 5’10” » Ball size: 65 cm/26”
  • Height: 5’11” to 6’4” » Ball size: 75 cm/30”
  • Height: 6’4” and up » Ball size: 85 cm/34”

Other than that, a good rule is that the smaller the ball, the bigger the challenge. So consider scaling up or down depending on your fitness level and how you plan to use yours. For example, tinier stability balls make for hardcore abs exercises, while a bigger one is beneficial if you intend to swap it in for a workout bench.

The benefits of working out with an exercise ball

Essentially, when you perform moves on an unstable surface, it requires you to engage even more muscles and thus is harder, Miranda explains. Case in point? Doing crunches on a stability ball fires your core muscles up more than doing them on a flat surface, according to a 2007 study.

For example, you can do a plank with your arms on an exercise ball (as demo’d below), which challenges you to stabilize in a different way.

An exercise ball also has a well-deserved place in your flexibility training routine; it’s especially useful when it comes to loosening up your hamstrings and lower back. Instead of just doing a basic forward fold and trying to touch your toes, Miranda recommends using the ball to slowly walk your hands in and out for a deeper stretch.

How to measure a fitness ball

Using a physio ball may also improve spinal stability, which can be particularly beneficial for those who spend a lot of time sitting (*raises hand*) and are prone to back pain, per research.

And, finally, any mistakes I should avoid?

Great question 👏 . Like with any piece of exercise equipment, safety comes first, so.

Steer clear of sitting on the ball to lift weights. “This will not increase core stability’ or cause the core to work harder, but rather increase spinal compression, especially if you’re sitting on a slightly flexed spine,” Miranda explains.

Instead, kneel on the ball, lie back on it with your feet flat on the floor, or balance on your stomach in plank pose to lift weights in order to reap those major core-boosting benefits.

Other than that, the, er, ball is really in your court for how you work one into your fitness routine.

Table of Contents

What is the largest exercise ball?

Choosing the Right Exercise Ball

Exercise ball diameter Person’s height
55 cm 5’1″– 5’8″
65 cm 5’9″– 6’2″
75 cm 6’3″– 6’7″
85 cm 6’8″ and taller

What size exercise ball should I buy?

Exercise balls come in industry-standard sizes: 55 cm, 65 cm, and 75 cm. These sizes indicate the height or diameter of the ball when fully inflated….1. Which size exercise ball should I buy?

CHOOSE YOUR BALL SIZE
Height Ball Size
5’0″ to 5’5″ Small: 55cm/22″
5’6″ to 5’11” Medium: 65cm/26″
6’0″ to 6’3″ Large: 75cm/30″

How much should I inflate my exercise ball?

Inflate the ball to 80% Place the fitness ball between the wall and the box and start pumping. If no pump is included, you can also use the pump for your air mattress. Pump up the ball until it touches both the wall and the box.

Can an exercise ball explode?

Exercise balls should be manufactured to be burst-resistant as rupture/explosion of a ball during use may result in serious personal injury. Unfortunately, since 2000, there have been at least 47 injuries reported due to exploding exercise balls.

How long does an exercise ball last?

Stability balls, depending on level of use, typically have a 12-month lifespan and should be replaced afterwards. Also, stability balls come with a range of burst limits ranging from 200 pounds to over 1,000 pounds.

Is exercise ball good for lower back pain?

While many people struggle with different physical limitations and resources, the use of an exercise ball is cost effective and relatively easy to use, while providing strong results. One of the most effective ways to reduce lower back pain is to strengthen the muscles around your spine.

Is sitting on a exercise ball good for you?

Claims that stability balls will strengthen your core have little backing in research. In fact, sitting on a stability ball, also known as a balance ball, exercise ball or Swiss ball, could have detrimental effects. Manufacturers often promote stability balls as both workout equipment and furniture.

Is sitting on exercise ball better than chair?

The idea of sitting on an exercise ball instead of a traditional office chair is that the instability of an exercise ball requires the user to increase trunk muscle activation and thus increase core strength, improve posture and decrease discomfort. Another benefit ball chair supporters claim is increased calorie burn.

Is sitting on a ball good for your lower back?

Low back injuries often restrict movement and may lead to the weakening of your lower back muscles. Exercise balls are a great option for a gentle back mobility and core-strengthening program that can stabilize the muscles surrounding your spine, improve motion and help prevent future injury.

Is sitting on a gym ball good for sciatica?

Many treatment programs for low back pain or sciatica incorporate use of an exercise ball to strengthen the core muscles in the stomach and back that support the spine. Using an exercise ball for strengthening is clearly an effective way for people with lower back pain problems to rehabilitate the spine.

Can sitting on an exercise ball hurt your back?

Any kind of sitting increases compression on your spine. Remember, the ball does not support your back muscles—it only challenges them. Compression combined with a lack of support may irritate any injury, condition or muscle imbalance you may have, and will likely increase your pain if used for too long.

How do you sit on an exercise ball instead of a chair?

Inflate the ball until you can sit on it with your feet resting flat on the floor and your legs at a 90-degree angle to the floor. Tighten your abdominal muscles and straighten your back. Relax your shoulders and place your hands on your desk. In the correct position, your arms will form a 90-degree angle.

What are the benefits of bouncing on an exercise ball?

You are also stimulating the muscles of the core — the deep pelvic, abdominal, and low back muscles — which are essential for good posture and balance and movement control, says Pire. The ball stimulates the smaller, stability muscles, says Ross, in addition to the muscles being used in the exercise.

Can you lose weight by bouncing on a exercise ball?

Stop Sitting and Start Bouncing. Well, trading in your office chair for an exercise ball can help you burn an extra 50 calories an hour, says personal trainer Monica Vazquez from New York Sports Clubs.

Can you lose weight sitting on exercise ball?

Answer: Sitting on a ball might help strengthen your core, but it won’t help you shed significant calories. The misconception comes, in part, from studies on nonexercise activity. Fidgeting, a common example, is often cited as a way to help burn extra calories.

Last Updated: November 5, 2020 References Approved

This article was co-authored by Adam Shuty. Adam Shuty is a Certified Strength and Conditioning Specialist and owner of ATOMIC Total Fitness, a fitness training studio in New York, New York. With over 15 years of experience, Adam specializes in weightlifting, strength and conditioning, and martial arts. Adam holds a BS in Industrial Engineering from Virginia Polytechnic Institute and State University. In 2014, Adam appeared on the Live With Kelly and Michael Show as one of the top five fitness instructors in the country.

There are 10 references cited in this article, which can be found at the bottom of the page.

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Exercise balls are a useful workout tool for strengthening your core and assisting with balance exercises, such as pelvic thrusts. The ball can be difficult for beginners because it creates an unstable surface, but with a little practice, an exercise ball can be a great tool and even help you use your muscles in new ways. [1] X Expert Source

Adam Shuty
Certified Strength & Conditioning Specialist Expert Interview. 26 August 2020. The best way to use an exercise ball as a beginner is to practice simple core and leg exercises to build your confidence.