If one is looking to make links between the various physiological systems, we can remain surprised! We recognize some basic roles of the vestibular system:
- Equilibrium and orientation in space.
- Control of blood pressure as it relates to the postural context.
As far as the control of blood pressure goes, this takes place via projections of the vestibular nuclei to brainstem areas that impact bone metabolism as there is activation of the sympathetic nervous system.
Recent studies (on rodents) suggest that a dysfunction of the vestibular system could alter the bone metabolism by having an impact on the projections of the sympathetic nervous system.
Generally speaking, we know that different factors can affect bone metabolism: age, oxidative stress and a reduction to resisting gravity.
The elderly and astronauts share three characteristics as it relates to a bone modeling disorder:
- A dysfunction of the vestibular system;
- An increase of activity of the sympathetic nervous system;
- Bone loss.
What needs to be stipulated is that an increase in sympathetic tone leads to bone loss. An increase of activity of this system is seen in weightlessness, for example.
So how can we potentially improve our balance and our bone strength? We can challenge ourselves by performing vestibular exercises to gain balance… and maybe more!