The walking ability in healthy older adults: The role of aging and physical activity and its interface with agility, balance, cognition, and risk of falls

Walking is the most basic and common means of locomotion. Walking requires integration and good levels of different physical and mental components and processes. A number of factors, including an inverse relationship with aging and the level of physical activity, can modulate the level of functionality of these components. In addition, the presence of chronic conditions such as sarcopenia, cognitive deficits, and specific changes mainly in frontal brain structures associated with the aging process may affect an individual's walking pattern. Moreover, walking performance demands integration with the environment and requires reasonable levels of balance, agility, and cognitive skills. Furthermore, walking demands performance in a multiple-task manner which is affected during the aging process due to impaired sensorimotor integration. Impairment in walking pattern along with reduced levels of agility and balance leads to an increased risk of falls. Despite the negative effects of aging on the human organism, regular exercise has been recommended as a means of reducing the rate of decline and maintaining functionality in older adults. Acknowledging the role that aging, physical activity, agility, balance, and cognitive functioning play in walking and also in the risk of falls, this chapter (i) describes how aging and physical activity interfere with walking pattern (stride length, speed, variability), agility, balance, and cognitive functioning and (ii) describes how these components contribute to either increasing or reducing the risk of falls in older adults. To accomplish these goals, scientific literature was reviewed, analyzed, and summarized.