Size of stability ball

[PennyLaney]

Hi Cathe,

I am 5'9.5", and bought a 65 cm stability ball based on my height. I have been having a terrible time even getting on the ball for the prone planks during PUB. I put my stomach on it and roll forward across the room until my shins are on the ball. Sometimes I roll across the entire room, and hit the wall! I CANNOT just crawl onto it like you guys do.

Today I decided to do my workout in front of a mirror, and noticed that my thighs were NOT parallel to the floor when sitting on the ball during the oblique twists. I also noticed that the top of the ball is at or a bit below the knees of you and all of your background exercises. The top of the ball is ABOVE my knees, and I have long legs.

Should I deflate my ball to be smaller? What specific guideline should I use for proper sizing?

Thanks,

PennyLaney

 

[Cathe Friedrich]

Hi Penny! Yes, deflate your ball. Not only will that provide you with a better "ball fit" but it will also provide a little more support since a slightly deflated ball increases the support base.

The standard method for determining proper ball size is by sitting on the ball. For most exercise applications, there should be a 90 degree angle at both the hip and knee joints and your thighs should be parallel with the floor when seated on the ball.
The general recommended size to height for stability ball selection is as follows:

55 cm. ball 21 inches 4' 11" - 5' 4" tall
65 cm. ball 25 inches 5' 5" to 5' 11" tall