Abstract
In general, aging is considered to be inevitable, progressive, irreversible and biologically universal. However, it is also true that aging is a highly individualized process, resulting in large inter-and intra-individual differences in health and function. These differences mean the possibility does exist that part of aging may be reversible. It is hypothesized that maintenance of high physical fitness, associated with regular involvement in exercise or physical activity, may delay the acceleration of aging(particularly the decrease in physical vitality). Physical fitness is a set of attributes that relate to one〓s ability to perform exercise or physical activity, consisting of cardiorespiratory(aerobic)fitness, muscular strength, flexibility, balance, and qualitative body composition(lean-to-fat ratio), etc. However, there is no consensus on the gold standard for direct measurement of the individual physical fitness elements. In this special issue, the following important components will be addressed by experts in the area of aging and physical activity : muscular fitness and its increase by training in older adults, assessment of balancing ability in older adults, biomechanical analysis of walking in older adults, assessment of cardiorespiratory fitness in older adults, the relation between functional capacity and physical fitness in older adults, and the association of lifestyle with physical fitness in older adults.
