An ever-growing body of literature on physical activity confirms that being active is more than a sign of good health among older adults. Physical activity offers a variety of health benefits as we age, such as improved aerobic capacity, increased physical strength, immune system benefits, and even cognitive benefits. It would appear obvious that physical activity changes in different seasons; indeed, research has proven this to be the case. It may be surprising, then, that there are little empirical data on how specific weather conditions influence physical activity among older adults. This may strike the skeptical reader as a trivial question—of course people spend less time moving around outdoors when the weather is cold and/or hostile—but to make the best use of research on physical activity, it is important to get a more systematic and scientific understanding of the influence of weather. If we are to best understand the utility and effects of the multiple physical activity interventions being promoted among older adults, it becomes important to understand which specific weather variables influence physical mobility and to what extent.
A study took such a systematic look at weather conditions, measuring specifics like precipitation, hours of daylight, average and high/low temperatures, humidity, and global radiation. The researchers recruited 1,505 adults age 65 and older in Germany and recorded their physical activity over seven days. Unlike most research on the physical activity of older adults, which uses pedometers to count steps, this study also examined the length of time spent walking and engaging in other activity. The researchers examined the relationship between physical activity and all the weather variables and found some results that show the need to look systematically at common-sense ideas about weather and physical activity—for example, while cold weather, humidity, and wind speed each negatively impacted physical activity, daylight actually became insignificant while controlling for the other weather variables, as did season.
This research contributes an important consideration to research on physical activity interventions. The study shows that it is necessary to include weather conditions when assessing the value of physical activity interventions for older adults, and that often-overlooked variables such as wind speed and global radiation need to be added to “common sense” measures such as temperature and precipitation. When we plan and study physical activity, we need to consider more than the time of year and the hours of sunlight.
Klenk J, Büchele G, Rapp K, Franke S, Peter S, (2011). Walking on Sunshine: Effect of Weather Conditions on Physical Activity in Older People.” Journal of Epidemiology and Community Health, Feb 15 2011, epub ahead of print