Balance Progressions
http://www.mountpleasantgranary.net/blog/images/Sitting-on-the-bench.jpg
Challenging and Progressing static balance control into functional activities include:
Decreasing visual input
Narrowing the base of support
http://upload.wikimedia.org/wikipedia/commons/1/13/Elderly_exercise.jpg
Adding Perturbations from One or More Directions
Note how this concept of stabilizing under dynamic conditions translates to musculoskeletal practice.
Changing the surface from firm to soft/dynamic
http://upload.wikimedia.org/wikipedia/commons/e/e3/Balance_with_one_leg.JPG