Final answer:
Excessive co-contraction during dynamic stability can lead to spasticity and hyperflexia, disrupting the balance maintained by the cerebellum and spinocerebellar tract. This could impair the check reflex, causing exaggerated and uncoordinated movements.
Step-by-step explanation:
During dynamic stability, excessive co-contraction of muscles might lead to spasticity, which is an increased contraction of a muscle in response to rapid stretching. This condition often results in hyperflexia, where there is an overly strong reflex response. In the context of the nervous system, particularly the spinocerebellar tract, which carries proprioceptive input to the cerebellum to help maintain balance and coordinated movement, excessive co-contraction can cause disturbances in this balanced system.
For instance, the check reflex, which is essential for preventing continuous muscle contraction after a resistance is removed, depends on the cerebellum to moderate these muscle contractions. An example of this is when picking up a mug considered to be full, but is actually empty, without the check reflex, the unexpected lightness could cause you to exert too much force, potentially throwing the mug. If excessive co-contraction occurs, the ability to swiftly moderate these actions is compromised, leading to uncoordinated and exaggerated movements.