Relationship between customary physical activity, muscle strength and physical performance in older men and women: findings from the Hertfordshire Cohort Study

Abstract

Sir—Maintenance of muscle strength and physical performance in later life is an important component of healthy ageing [1–4]. Reported influences include age, gender, size and physical activity [5–7]. Older age has been linked to lower strength [8, 9], but these studies have not considered how age-related decline in activity levels may contribute to these changes. A study of grip strength in older people found that it declined by 20% per decade but only 11% of this decline could be attributed to age alone [10]. Older people are encouraged to maintain levels of physical activity, but most evidence considers the benefits of exercise and strength training intervention programmes [11–13]. It is important to quantify activity levels corresponding to levels of benefit in general, as well as defining specific outcomes related to particular activities in both men and women. Epidemiological studies suggest that increased customary physical activity is associated with improved muscle strength and physical performance, but it is unclear whether men and women derive similar benefit [14–17]. For example Bassey et al. found a positive association between usual physical activity and muscle strength in both men and women [18], whereas Rantanen's study of everyday physical activity in older people showed the importance of activities such as housework, walking and gardening in maintaining independence for women [19]. The objective of this study was to investigate the relationship between customary physical activity, muscle strength and physical performance in older men and women.