What is Exercise

In being seated, standing, and walking, many uncontrollable factors contribute to the degradation of our balance system. The maintenance of balance involves many essential sensory (visual, vestibular, and somatosensory) and motor processes. Each sensory input provides unique internal and external reference frame information to the central nervous system (CNS). The CNS interprets the sensory information, from which preplanned and/or preventative (feedforward controls) and corrective (feedback controls) actions can be taken and conflicting sensory information can be mediated (Peterka, 2002). In the absence of a sensory input, balance can still be maintained; however, the compensatory actions become larger and different balance strategies may be employed. Serious problems facing older adults and many people with neurological disorders (e.g., stroke, traumatic head injuries, incomplete spinal cord injuries, Parkinson’s, multiple sclerosis, diabetic peripheral neuropathy, and osteoarthritis) are balance impairment, mobility restriction, and falling (Gill et al., 2001; Harris, Eng, Marigold, Tokuno, & Louis, 2005). In these cases, even small disturbances may result in a fall and injuries are very likely to occur. This increased risk of falling combined with mobility limitations precipitates patient dependency in instrumental and basic activities of daily living; in turn, this results in reduced levels of physical activity.