Effect of intensity and type of physical activity on mortality: results from the Whitehall II cohort study

Objectives. We examined the association of intensity and type of physical activity with mortality.Methods. We assessed the duration of physical activity by intensity level and type in 7456 men and women from the Whitehall II Study by questionnaire in 1997–1999 (mean ±SD age = 55.9 ±6.0 years) and 5 years later. All-cause mortality was assessed until April 2009.Results. A total of 317 participants died during the mean follow-up of 9.6 years (SD = 2.7). Reporting at least 1 hour per week of moderate activity was associated with a 33% (95% confidence interval [CI] = 14%, 45%) lower risk of mortality compared with less than 1 hour. For all physical activity types examined, except housework, a duration of physical activity greater than 0 (≥ 3.5 hours for walking) was associated with lower mortality in age-adjusted analyses, but only the associations with sports (hazard ratio [HR] = 0.71; 95% CI = 0.56, 0.91) and do-it-yourself activity (HR = 0.68; 95% CI = 0.53, 0.98) remained in fully adjusted analyses.Conclusions. It is important to consider both intensity and type of physical activity when examining associations with mortality.The dose-response association between physical activity and all-cause mortality is well established,^1,2 but few studies have investigated whether the different types of leisure-time physical activity are equally beneficial.^3–5 There are a variety of ways to expend energy, such as sports, walking, and domestic physical activity, and different types of activities require different levels of energy expenditure.⁶ Sports activities have been clearly shown to be associated with a lower risk of mortality.^3,5,7,8 However, less is known about less intensive physical activities, particularly those that are a part of daily living and leisure. Two recent reports showed “global domestic activity” to protect against all-cause mortality,^3,5 and a previous article on Finnish data suggested that specific types of domestic physical activity may have a protective effect.⁴ Our objective in the present study was to examine the associations of mortality with intensity, in terms of mild, moderate, and vigorous activity, and type of physical activity, specifically, walking, sports, housework, gardening, and do-it-yourself activities.