What is a BOSU ball?
Perhaps a better way to refer to the BOSU ball is as the “half blue exercise ball”. It is essentially a stability ball on one side and a hard flat surface on the other. Both sides can be used for various balance exercises. For this reason it is called BOTH-SIDES-UP, or BOSU. See More Here
Why should you use it?
The primary reason I use a BOSU ball is to challenge my stability and balance. Stability is the foundation of performing functional movement and progressing towards strength exercises.
For example, performing a single leg bent over row on a BOSU ball is one way to challenge stability and balance throughout the ankle, hips, and spine. The BOSU will create an unstable surface which triggers the muscles of the ankle, hips, and spine to work harder to stabilize the body throughout the exercise. This means that the muscles around those joints, primarily the calves, glutes, and core, will develop greater endurance to make sure the body can remain in proper joint alignment, or posture, throughout the movement. Better posture means better movement and better movement means less likely to be injured.
Another exercise example is the single leg balance to reverse lunge plus overhead kettlebell hold.
In this example, the shoulder joint is also challenged in addition to the ankles, hips, and spine, in order to develop greater stability. Greater stability in the shoulder joint means the muscles of the scapula will have the endurance to sustain and control any overhead movement you might perform in daily life such as carrying a heavy box or reaching for something heavy on a high shelf.
Here is an example of a BOSU ball circuit that I like to perform.
Sets and Reps
Single Leg Bent over Row: 2 sets of 8-12
Single Leg Balance to Reverse Lunge: 2 sets of 8-12