Physical activity, interleukin-6 change, and gait speed

Abstract

Aging can be associated with a decline in physical function that eventually leads to a loss of autonomy in the activities of daily living (ADL). In particular, mobility is the most studied and most relevant physical ability affecting quality of life with strong prognostic value for disability and life expectancy [1]. In fact, walking is a component of ADL, and it is important for the main determinants of quality of life in older age such as maintaining independence in ADL, enjoying an adequate level of social interaction, and retaining good emotional vitality [2]. In older adults, gait speed has been described as the ‘sixth vital sign’ because it is a core indicator of health and function in aging and disease [2]. In fact, gait speed is an objective measure of physical functioning, with slower performances associated with mobility disability and other adverse health-related outcomes in older age [2]. Gait speed lower than 0.8 m/sec may be a reliable cut-off to identify subjects at increased risk for disability, hospitalization, institutionalization, and increased mortality [3], while improvement of usual gait speed may ensure a longer survival in older adults [4]. Gait speed measured over long distances (400 m) is a good indicator of cardio-respiratory fitness, and it may be a better early indicator of the overall physical health compared to gait speed over short distances [2].