Twitter / Facebook Links
« Your Core: Training the obliques while stabilizing the spine. | Main | Walk this Way - Tips, Tricks and Walking Groups from Heart Strong Fitness »

Be Size Wise: A guide to selecting an appropriate exercise ball. 


We often design clients’ exercise programs to include seated ball exercises and core exercises which utilize a stability ball. The purpose of using the ball is that it creates an unstable surface, which promotes increased core engagement and thus creates stronger core muscles. If someone is new to exercise or stability ball exercises, choosing the right ball can be a little intimidating. In addition, if your ball is not the right size, those seated exercises may actually do more harm than good!


Here are some tips for choosing a ball that is the right fit for you:


If you are at a gym or facility where there are multiple ball sizes to choose from, have a seat on the ball. 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.

Alternatively you can use this handy ball size/height chart. Exercise balls come in industry standard sizes: 45cm, 55cm, 65cm, 75 cm and 85cm.

Things to keep in mind if you are using this chart to purchase a new ball that is not inflated:

  • 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.

  • 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. 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 floor 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.

  • If purchasing a ball that indicates it is “Anti-Burst” this means if the ball were punctured or had a small hole, it would slowly deflate. If the ball is not “Anti-Burst” it could burst like a balloon. The anti-burst is an important safety feature of higher quality balls and should also indicate the maximum weight it can support.


PrintView Printer Friendly Version

EmailEmail Article to Friend

Reader Comments

There are no comments for this journal entry. To create a new comment, use the form below.

PostPost a New Comment

Enter your information below to add a new comment.

My response is on my own website »
Author Email (optional):
Author URL (optional):
Some HTML allowed: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <code> <em> <i> <strike> <strong>