To prevent older adults from settling into an unhealthy sedentary lifestyle, public health policies have been implemented to promote physical activity, which is essential for maintaining good health. Researchers from Inserm and Université Paris Cité within the Center for Research in Epidemiology and Statistics have studied the impact of individual sociodemographic, behavioral and health factors on the practice of daily physical activity in later life, using data from 3,896 participants of the Whitehall II cohort. This research, published in JAMA Network Open, highlights the complexity of individual barriers to an active lifestyle among older adults and suggests that this complexity should be better taken into account when redefining public health policies.
By maintaining many essential functions that prevent chronic disease and mortality, physical activity is one of the keys to healthy aging. Although it is currently recommended to do 21 minutes of moderate to intense physical activity per day and reduce the amount of time spent sitting (being sedentary), few people actually follow this advice – especially older adults. In addition, public health messages aimed at older adults take little account of individual factors, whether environmental or personal, that may limit the adoption of an active lifestyle.
A team led by Séverine Sabia, Inserm researcher at the Center for Research in Epidemiology and Statistics (Inserm/Université Paris Cité), studied the factors that influence physical activity and sedentary behavior in later life.
The scientists looked at data from Whitehall II1, a British cohort of which 3,896 of its participants, between 60 and 83 years of age, had worn a measuring device for a nine-day period in 2012-2013. This device, called an accelerometer, continuously recorded data on the intensity and duration of their daily physical activity. In addition, data relating to their sociodemographic characteristics (age, sex, ethnicity, occupation, marital status), behaviors (consumption of tobacco, alcohol, fruits and vegetables), health (body mass index, quality of life, chronic diseases) and physical activity were collected between 1991-1993 and 2012-2013, representing a 20-year period prior to the accelerometer measurements.
In terms of physical activity, the researchers considered three levels of intensity: sedentary (low-energy activity while sitting or lying down), light (e.g. slow walking), and moderate to vigorous (e.g. swimming, cycling).
Their first finding was that men spend more time being sedentary or engaging in moderate to vigorous activity than women, who spend more time than men doing light physical activity.
Depending on the factors studied, a longer duration of time spent being sedentary by older adults had differing effects on the duration of the other levels of intensity. For example, in comparison with those living with partners, people living alone spend on average an additional 11 minutes being sedentary, mostly at the expense of time devoted to light physical activity. In contrast, although a five-year age difference results in a similar increase in time spent being sedentary, this comes at the expense of time devoted to moderate to vigorous activity – which is more than half the recommended daily time (21 minutes).
The behavioral factors all appear to impact the time devoted to the different levels of intensity. The largest difference is seen with male smokers, who spend 37.4 more minutes per day being sedentary, at the expense of 23.3 minutes of light activity and 14.1 minutes of moderate to vigorous activity (i.e. two-thirds of the time recommended for the latter). However, in women who smoke, the increase in sedentary time comes at the expense of moderate to vigorous activity.
Among the factors relating to health status, poor general health, the presence of chronic diseases, and obesity are associated with a significant increase in the time spent being sedentary.
The largest discrepancies are seen with obesity: at the same age, people with obesity spend 50.7 minutes longer per day being sedentary than those with a normal body mass index, at the expense of 28.6 minutes of light activity and 22.1 minutes of moderate to vigorous activity – i.e. all of the time recommended for the latter.
In general, for women, nearly all of the factors impact the time spent on the different intensities of physical activity – an impact that is similar but globally attenuated in comparison with men.
“We wanted to know if barriers to physical activity among older adults were already present earlier in life and we found that they were. Living alone, being overweight or obese, the presence of chronic diseases, poor physical functioning or poor lifestyle at the average ages of 50 and 60 were associated with low activity levels in later life,” explains Mathilde Chen, lead author of the study. We were also able to see a clustering of behavioral risk factors: people who are more sedentary tend to smoke and eat fewer fruits and vegetables. This research reflects the complexity of the determinants of an active lifestyle among older adults. “
Séverine Sabia, study investigator, concludes: “In the fight against the health impacts of high levels of inactivity among older adults, this research provides arguments in favor of targeted prevention strategies, integrating all components of physical activity and healthy lifestyle behaviors, and addressing as early as possible those who are most likely to be sedentary in later life. “
1 The Whitehall II cohort was set up between 1985 and 1988; a total of 10,308 British participants (67% male) aged 35-55 years were recruited and have been followed up ever since.