Repeatedly in the training world, we see the addition of an unstable surface as a means to make an exercise more ‘functional’. But what is the real outcome when incorporating bosu balls, swiss balls, airex pads, etc. when working with clients? Are we making clients stronger? Are clients able to transfer energy more effectively and efficiently when repeatedly working in a state of instability? Are we truly making our programs more ‘functional’?
Whether it is for sport performance or everyday life, function is key. When considering function, the continuum is endless; we must be able to transfer energy from the ground up (picking up a box), or to an implement we may be holding (golf club) for a powerful swing.
Stabilization and balance have often been mistakenly defined as the same thing or used interchangeably; however each are independent concepts in the strength and conditioning world.
By definition, stabilization is “to become stable, firm, or to be resistant to disturbance of equilibrium.” For example, a bridge must be stable to allow cars to safely travel its length. Alternatively, the definition of balance is “an even distribution of weight enabling someone or something to remain upright and steady,” for example maintaining balance on a boat rocking back and forth.
Observe these 2 images:
Left image shows a well-balanced, but unstable structure. Right image is a much less balanced, but stable structure that can withstand external forces and will not likely collapse.
Further exploration of the above two concepts within the training world and how they differ is multifactorial. Balance has a place in the realm of health and wellness/rehabilitation. When programming for ‘function’ we must create an environment of stability to enhance strength and “practice” the skill of energy transference. Having a direct connection with the ground and using ground reaction forces will allow your client to hit a baseball harder, punch an opponent more powerfully or jump higher to grab a rebound. The forces must be able to transfer from lower extremity, through a rigid core, and continue to the ‘exit’ point.
Creating an environment of “instability” by way of BOSU ball or airex pad usage, will simply allow your client to practice balance while causing dissociation between the joints of the body. When there is dissociation of joints within the lower extremity, energy transference will be negatively affected from joint to joint to core through to the exit point. A study done by Willardson JM, et al. (2009) revealed that there were no significant advantages with respect to core activation when using the BOSU balance trainer. Furthermore, ground reaction forces will be dispersed (lost) through the unstable device minimizing the return of energy back to the body.
Behm DG, et al. (2002) demonstrated that unstable devices account for 44% less muscle activity and 70% less muscle force output than stable surfaces. To practically apply these findings, perform a max squat strength test (3RM or 5RM) on 2 airex pads or any unstable surface device then do the same squat test without the unstable surface device and compare the final numbers.
What is the take home message from this? Program for functionality. Make your program functional by creating a stronger, more stable person able to withstand forces from the external environment.
The use of perturbation, or the “deviation of a system, moving object, or process from its regular or normal state of path, caused by an outside influence” can be used to accomplish this. Perturbation exercises are designed to be unpredictable and to elicit reactivity responses from client; just as required in game scenarios. A trainer or partner can apply unpredictable forces to an athlete, for example throwing balls at them or using a reaction stick to elicit maximum core stabilization, reactivity and force generation.
The ability to jump higher or hit farther will forever be more impressive than standing on a BOSU performing bicep curls or squat and shoulder press - program for strength and stability.