So, I finally finished and submitted my article to the Journal of Strength and Conditioning, titled: Is Unstable Surface Training Advisable for Healthy Adults? For those of you who are not familiar, unstable surface training is when you perform exercises on unstable devices like Swiss balls, BOSU trainers, wobble boards or foam pads. These devices are pretty common, but often misused. Instead of giving you a long sciencey article to read, I will summarize it with seven important points.
1. Unstable surface training developed in physical therapy for the rehabilitation of knee and ankle injuries.
2. Muscles around a joint increase activity when that part of the body is upon an unstable surface (for example; the abdominal muscles when you are lying on an unstable surface, and ankle stabilizers when standing upon an unstable surface).
3. Core muscle activity increases when you move from a stable surface to an unstable surface for many exercises with smaller amounts of weight or body weight.
4. You can't lift as much weight on an unstable surface as you can on a stable surface. Without stable surface training, it can be challenging to continue to improve strength (progressive overload).
5. Core muscle activity increases as you lift more weight. Much more core muscle activity when squatting, deadlifting, or pressing a heavier weight than performing core-specific exercises on an unstable surface.
6. Performing exercise on an unstable stable surface improves stability on an unstable surface, but there is little carry-over to stable surface performance- it is not"functional".
7. Beginners can see improvements in core stability with unstable surface training, however experienced individuals don't show much increase in core muscle activation on an unstable surface and can actually see a decrease in stable surface performance with unstable surface training-specificity of training.
My conclusion was: Unstable surface training can be used to improve core muscle stability with beginners. It can also be used to increase balance and reactivity in individuals who have deficits from an injury/surgery. Beyond these applications, unstable surface training probably won't be any better than stable surface training and can actually detract from performance in highly-trained individuals.