The researchers surveyed 284 members of a nationwide running club and 156 healthy controls who were recruited from university faculty and staff. All participants were age 50 or older when the study began in 1984. They completed a mailed questionnaire annually through 2005, providing information on exercise frequency, body mass index and disability level.
At the beginning of the study, runners were younger, leaner and less likely to smoke than controls. After 19 years, 81 runners (15 percent) had died compared with 144 controls (34 percent). Disability levels were lower in runners at all time points and increased in both groups over time, but less so in runners. At the end of the 21-year follow-up, in terms of disability, "the higher levels among controls translate into important differences in overall daily functional limitations," the authors write. "Disability and survival curves continued to diverge between groups after the 21-year follow-up as participants approached their ninth decade of life."
Regular exercise could reduce disability and death risk by increasing cardiovascular fitness, improving aerobic capacity, increased bone mass, lower levels of inflammatory markers, improved response to vaccinations and improved thinking, learning and memory functions, the authors note.
"Our findings of decreased disability in addition to prolonged survival among middle-aged and older adults participating in routine physical activities further support recommendations to encourage moderate to vigorous physical activity at all ages," they conclude. "Increasing healthy lifestyle behaviors may not only improve length and quality of life but also hopefully lead to reduced health care expenditures associated with disability and chronic diseases."
