Current issues of ACP Journal Club are published in Annals of Internal Medicine


Etiology

Lower mortality and disability was found in older persons who run

ACP J Club. 1995 Jan-Feb;122:23. doi:10.7326/ACPJC-1995-122-1-023


Source Citation

Fries JF, Singh G, Morfeld D, et al. Running and the development of disability with age. Ann Intern Med. 1994 Oct 1;121:502-9.


Abstract

Objective

To determine whether regular vigorous running is associated with lower mortality and slower development of disability in older persons.

Design

Cohort analytic study with 8-year follow-up.

Setting

The 50+Runners Association and the Stanford University community.

Participants

451 members (mean age 58 y, 83% men) of a runners' club and 330 community controls (mean age 61 y, 56% men) who were 50 to 72 years old when enrolled in the study. Participants were also classified as ever-runners (n = 534) and never-runners (n = 247).

Assessment of risk factors

Running behavior was measured in 3 ways: 1) membership in a running club; 2) running mileage; and 3) lifetime history of vigorous running for ≥ 1 month. Age, sex, body mass index, comorbid conditions, educational level, mean blood pressure, initial disability level, and family history of arthritis were collected by questionnaire at yearly intervals. Radiologic evidence of osteoarthritis of the knee was assessed in a subsample.

Main outcome measures

Mortality and disability were assessed by the Health Assessment Questionnaire.

Main results

At baseline, runners were younger, had lower body mass indices, reported joint symptoms less frequently, took fewer medications, had fewer medical problems, and had fewer instances of and less severe disability. The 8-year mortality was 1.5% in the runners group compared with 7% in the control group. The conditional risk ratio for community controls compared with runners was 4.27 (95% CI 1.78 to 10.26) after adjusting for age, sex, body mass, smoking behavior, alcohol intake, comorbid conditions, educational level, and mean blood pressure. After 8 years, the mean disability level at baseline (0.026 compared with 0.079, P< 0.001) increased to 0.071 for runners compared with 0.242 for the controls (P < 0.001). The rate of development of disability was several times slower among runners than among controls, even after adjustment for baseline differences in the groups. Slower development of disability was seen for both men and women who ran. Similar results occurred when running was classified according to running mileage and lifetime running history. The postponed development in disability among runners was not explained by postponed development of osteoarthritis.

Conclusion

Older persons who engage in vigorous running had lower mortality and slower development of disability than did members of the general population.

Source of funding: National Institutes of Health.

For article reprint: Dr. J.F. Fries, 1000 Welch Road, Suite 203, Palo Alto, CA 94304-1808, USA. FAX 415-723-9656.


Commentary

The study by Fries and colleagues is an important addition to the limited amount of epidemiologic research on physical activity and disability. The observation that physical activity slows the development of disability is consistent with previous research (1). An important finding in the study by Fries is that the benefits of exercise occurred in both men and women and in all age groups studied. Unlike most previous studies that measured overall activity levels, this study measured a single type of physical activity: running exercise. It is important to know that doing a specific activity may protect against disability.

It was not the aim of the study, however, to compare running exercise with other types of activity and, as noted in this article, adults who run also tend to do other types of exercise. Therefore, the most likely interpretation of these findings is that running is only 1 of many activities that may prevent disability. Although running is a relatively vigorous pursuit, it is likely that moderately intensive activities also protect against disability. Vigorous activities have some risk for injury, and, indeed, in this study, runners had more sports-related and fall-related fractures than did nonrunners.

The clinical wisdom of the past was that exercise causes "wear and tear" that makes arthritis worse. The radiographic and questionnaire data from this study provide additional evidence for the present view that reasonable amounts of exercise do not necessarily exacerbate arthritis.

David M. Buchner, MD
University of WashingtonSeattle, Washington, USA


Reference

1. Wagner EH, LaCroix AZ, Buchner DM, Larson EB. Effects of physical activity on health status in older adults. I: Observational studies. Annu Rev Public Health. 1992; 13:451-68.