What is a Bosu?

It is an unstable hemispherical shaped surface.

It can be used by turning the flat side upside down or face up.

We can use it to work the lower body, the upper body or the core area, in a leading way. What they have in common is that the instability of the surface will force us to readjust and will try to destabilize us.


We need to clarify a few things:

Instability is not the same as Perturbation

Bosu instability provides a consistently uneven surface. We can adapt to it better or worse, it can dominate it, but from the beginning, we are clear about what there is and that instability will not change.

A perturbation is simply an external element that forces us to readjust ourselves either due to its variability or impact, since the disturbance usually appears by surprise and unpredictably.

(Perturbation: Alteration or disorder that occurs in the permanent characteristics that make up a thing or in the normal development of a process)

Now think, which of the two situations produces more injuries in your sport?

The type of work it offers a Non-specific:

Cuanto más respete un ejercicio o actividad las condiciones del juego real, más especificidad, y por lo tanto más transferencia a situaciones que posteriormente el deportista se pueda encontrar en su realidad competitiva.

The more an exercise or activity respects the conditions of the competition, the more specificity, and therefore the more transfer to situations that the athlete may later encounter in his competitive reality. 

Knowing this, it is very easy to understand the following: In a flat surface, there are no uneven surfaces. Is learning to “live” on an uneven surface, learning to work on a flat surface? No. If, instead, I dedicate myself to doing mountain races, with uneven terrain, then I could have more utility, transfer and specificity.

“But if I step on someone in a game or training, that could be considered an uneven/unstable surface, right?”

When you step on someone while playing, a change of direction or after falling from a jump, do you do it with the same intensity as when you work in the bosu?

If the answer is no, it is still unspecific work because the intensity is not real. If the answer is yes, assess the risk of that job and you decide if it compensates you, since there are other safer alternatives to improve these motor patterns. 


So, what are the bosu benefits?

The unstable surface can be an interesting resource to use as a specific stimulus, considering that it will force me to adapt to something new, it will activate my body consciousness, I will discover if I dominate my body in that situation or not, and it can bring variability and new stimulation to training, understanding that I am working nonspecifically. This will not replace later a more specific work, in conditions closer to my competitive reality, regarding intensity, surface, supports and neuromuscular activation.



1. Like most resources, it will be useful depending on how we use it. The goal and the needs of the athlete, always go above and beyond the exercise, no matter how beautiful or visual it may be.

2. It is necessary to contextualize what type of work it brings me, what it is for me (for my sport and for my athlete/s)  and when I am interested in using it or not, and why.

3. I am not going to throw away the bosu, but what I am not going to do, is teach an athlete to live in an unreal situation and different from the one that will be found in the competition, believing that I am getting closer to his competitive reality.

Key words: Instability, Perturbation, Specificity.