Is there a motor reserve in the cerebellum?

As young adults, people normally do not experience problems with the control over their movements. However, even during healthy aging, motor control problems occur and things that used to be natural like learning a new movement or judging the force needed to pick up a bottle can become problematic. But what are the underlying mechanisms of these changes?
Following a leading theory in this field, it is thought that the control of our movements is achieved through so-called internal models that help us predict the consequences of our movements even before we could have a feedback of it through our senses, allowing us to correct eventual errors without delay. These internal models depend on a brain area called cerebellum that is heavily affected by aging.
The currently accepted hypothesis is that the age-related cerebellar degeneration is directly causing a deficit in motor function. Yet, we believe that this theory is not consistent with the absence of difference in motor performance between young (<35 years old) and old (>55 years old) participants in tasks that rely on cerebellar function. Therefore, the goal of this project is to investigate the actual link between age-related changes in motor performance and cerebellar structure. We hypothesize that the cerebellum acts like a motor reserve. That is, it the cerebellum is resilient to damage and age-related cerebellar degeneration does not directly impact motor function in general and cerebellar function in particular.