Exercise Ball Size

Make sure you start with the right exercise ball size for you. Physical therapists have provided the table you see below for the general population, but ultimately the right size is dependent on the type of exercises you intend to do.

For example, the perfect exercise ball size for exercise ball exercises that require you to sit on the ball is dependent on your height. When sitting on the exercise ball, knees and hips should be at 90 degrees. For exercise ball exercises that require you to kneel or stand on the ball, a larger ball is better.

For those of you just getting familiar with the exercise ball, choose a larger size and keep it slightly deflated until you learn how the exercises feel and you feel comfortable balancing on it.

In my clinic I use a variety of sizes depending on my patients' abilities, height, pathologies, and goals. Balls are so inexpensive now it is helpful to have more than one.

More information on buying a ball.

Exercise Ball Size General Guidelines
BALL DIAMETER      YOUR HEIGHT
     45 cm      up to 5' 0  (1.5m)
     55 cm      5'0" to 5'6"  (1.5-1.7m)
     65 cm      5'7" to 6'0"  (1.7-1.8m)
     75 cm      6'0" and over
 
Use comfort as your guide.

For exercises that require sitting:

  • You should be able to sit in a comfortable position with hips and knees at approximately 90 degrees.
  • feet should be flat on the floor with weight distributed equally between the two feet.
  • Head should remain aligned over your shoulders without leaning.
  • You may slightly inflate or deflate the ball if you feel you are between sizes.
  • Using different sizes of balls will allow you flexibility and variation as you progress with the exercise ball exercises.

For exercises that require standing:

The bigger the ball the heavier it is, so if your are using it for upper extremity workouts, keep that in mind. If you lack shoulder strength or scapular stability you may want to use a smaller ball for exercises such as the isometric shoulder exercise  hold-up 1  or  hold-up 2, or the dynamic exercises  wax-on/wax-off,  or  wall push-ups.

For exercises that require you to support yourself against a wall such as the  squats,  side squats,  and  calf raises,  size is not as important. The ball in these exercises helps to guide you into proper body mechanics.



You may find that one brand of 55 cm ball may be bigger than a 55 cm ball of another brand. Try different sizes of balls for different exercises and be prepared to return a ball you bought because it didn't meet your needs. There are no hard and fast rules. Using different size balls will allow you more flexibility and variation with your exercise ball training.
We recommend beginning your program with a softer ball if you've never used an exercise ball before. The softer ball will provide greater contact with the floor and therefore more stability while doing the exercises. The firmer the ball, the more difficult you will find it to stabilize yourself on the ball. The more inflated the ball is, the less contact area there is with the floor, the more easily the ball will roll, and the more skill is required to maintain balance on the exercise ball.

Be sure to read the exercise ball precautions before beginning your workout program.