Study examines relationships among life-changing events and decreased physical activity

UC Berkeley School of Public HealthJun 6 2014

Adults tend to engage in less leisure-time physical activity (LTPA) after changes in both lifestyle and physical status, finds a new study in the American Journal of Preventive Medicine.

"To the best of our knowledge, this is the first study to examine the relationships among a cluster of life-changing events and decreased physical activity in men and women ," the authors wrote. "Over the 16-year period, an average of 32 percent of the respondents decreased their LTPA levels."

The researchers used data from the Canadian National Population Health Survey between 1994 to 2005 and 2008 to 2009 to assess the association between life-changing events and decreased LTPA during any 2-year period and found that nine out of 10 people changed LTPA levels.

The researchers defined life-changing events in three categories: sociodemographic, lifestyle and psychological, and physical. Changes in sociodemographic factors included income, education, employment status, and marital status. Changes in lifestyle and psychological factors included smoking, alcohol consumption, happiness, and social support, and changes in physical status included body-mass-index (BMI), health status, body pain, long-term disability and chronic diseases.

"In public health, we look at a number of issues related to modifiable risk factors, and physical activity is always one of those," said Margaret de Groh, one of the supervisors of the study.

"I was surprised that men who experience the life change of getting married tend to get complacent and back off on physical activity within a two-year period," she said. "In public health, we can flag this for intervention in messaging to men—there was no such relationship for women, however."

De Groh also noted that women who were physically active and then gained weight or remained overweight tended to reduce physical activity. "That suggests some discouragement or maybe giving up, and that's another area we would like to investigate further."

The study underscores the lifelong challenges people face in maintaining leisure time physical activity, de Groh observed. "But we want people to remember that even if they're at an unhealthy weight, physical activity provides a protective effect and has so many benefits for reducing the risks of major chronic disease."

"Physical activity is a very important predictor of cardiovascular health," said Kristine Madsen, M.D., M.P.H., assistant professor in the Joint Medical Program & Public Health Nutrition at UC Berkeley School of Public Health. "It is concerning, though not surprising, that this study shows a decline in physical activity over time among adults."

One finding is particularly worrisome, Madsen noted, "that those with more education were less likely to decrease their LTPA. A major public health goal is to decrease health disparities, such as higher rates of obesity seen in low versus high-income neighborhoods. The fact that obtaining more education is associated with higher levels of physical activity only widens the health disparities gap."