The Complete Book of Running

Book cover

By: Jim Fixx

Date: 1977

Source: Jim Fixx. The Complete Book of Running. New York: Random House, 1977.

About the Author: James F. Fixx (1932–1984) wrote the best-selling book, The Complete Book of Running. His book helped to launch the running and jogging boom in the United States and worldwide. In an ironic twist of fate, Fixx died at the age of fifty-two while jogging, only seven years after his famous book was published. The cause of death was a heart attack brought on by extensive coronary artery disease, a disease that also had killed Fixx's father at age forty-three.

INTRODUCTION

At the age of thirty-five Jim Fixx transformed his lifestyle by quitting smoking and starting to run for long distances. In an increasingly sedentary society, he became an articulate advocate for a healthy way of life focused on an improved diet coupled with intensive and prolonged aerobic exercise. His untimely death at fifty-two while pursuing his favorite activity had virtually no negative impact on the growing popularity of running and other aerobic activity. Many people saw his death while jogging as a coincidence that did not undermine the validity of Fixx's advocacy of this and other aerobic activities.

In 2005, 75,000 runners applied to enter the New York City Marathon, which accepts half of the applicants using a lottery system. From 1984 to 2003, the number of runners completing marathons in the United States increased from 170,000 to 400,000 according to the U.S. Track and Field association. The many runners seen daily on paths in city parks and alongside suburban streets illustrates that Jim Fixx had a lasting impact on the way that Americans use their leisure time and maintain health and fitness. Yet, the nation is still beset with rising rates of chronic disease related to obesity and a sedentary lifestyle.

PRIMARY SOURCE

THE COMPLETE BOOK OF RUNNING

See primary source image.

SIGNIFICANCE

Jim Fixx's death while jogging demonstrates a paradox about the risk of sudden death and exercise. Running poses some risks. Studies from Seattle and Rhode Island calculated that the number of persons who die annually from heart attacks while exercising is one out of 15,000. The Rhode Island study used data on all deaths during jogging from 1975 through 1980 in that state. Data analysis revealed that one death occurred annually for every 7,620 male joggers between the ages of thirty and sixty-five. When patients with known coronary artery disease were eliminated from the analysis, the annual incidence of sudden death was one death per year for every 15,240 previously healthy joggers. In spite of survey bias and other methodological limitations, the sudden death rate for healthy subjects was similar to a later estimate from Seattle of one death for every 18,000 physically active males.

The Seattle study also examined the sudden death rate based on accustomed activity levels. The authors observed that regular exercise both reduces the probability of sudden death during exercise and temporarily raises the risk of myocardial infarction (MI) even among individuals who regularly exercise, but men who spent more time during the week exercising had a lower risk of sudden death. Using these data and taking into account that active men exercise more hours and therefore have a lower risk per hour of exercise than sedentary men, the annual risk of sudden death during exertion is one death per 17,000 in men who spend 1-19 minutes per week in vigorous activities, one death in 23,000 for men who expend 20-139 minutes per week, and one death per 13,000 men who expend more than 140 minutes per week.

Both of these studies use old data and found very low total numbers of deaths: ten deaths in Rhode Island and nine in Seattle, indicating that statistical inference from these studies might not be highly reliable. A more recent study of runners in the Marine Corps and Twin Cities Marathons between 1976 and 1994 suggests one death per 50,000 participants.

While runners and others who engage in strenuous exercise appear to be more at risk during their training time, especially if they run marathons, they appear to have a much lower risk of death than the general population for the remainder of the day. Many studies suggest that rigorous aerobic training can actually extend peoples' lives and improve their overall health. A prospective study of Harvard University alumni concluded that people can live an extra two years or more by engaging in light exercise regularly. In this study, men who burned 2,000 kilocalories per week performing cardiovascular exercises had a 25 to 33 percent lower death rate. Notably, the rate of coronary artery disease was decreased by 41 percent in the group that regularly exercised, compared to those who did not participate in cardiovascular exercise. Other studies indicate that regular exercise and a healthful diet may extend life spans by six to nine years.

The risk of MI also is related to an individual's usual fitness level. A study examined the relative risk of suffering MI during or within one hour of exercise. In this study the relative risk of MI during or just after exercise was at least 5.6 times greater than the risk during less vigorous activity. Common activities associated with MI included lifting or pushing (18 percent), isotonic activities such as jogging (30 percent) and yard work such as gardening and chopping wood (52 percent). In patients who were usually sedentary, the relative risk of MI was 107 times higher during exercise than it was at rest. Among those who regularly exercised at least five times a week, the relative risk was only 2.7 times higher than it was at rest. Patients with diabetes had a relative risk of exercise-related MI that was 18.9 times higher than their risk at rest.

The best conclusion based on current information is that the additional risk of sudden death during exercise is proportional to the difference between a person's usual activity level and the transient activity level while exercising. Furthermore, there is a temporary period during and immediately after strenuous exercise in which an individual is at a significantly increased risk of sudden death. This risk is reduced by more regular exercise and a higher level of physical fitness. Jim Fixx's death while running could have been used to demonstrate the risks of exercise and its inability to reverse inexorable cardiovascular decline. Instead, his death seemed to spur an ongoing increase in research into the specific risks and health benefits of exercise.

Fixx was an evangelist for the beneficial effects and enjoyment of exercise, running, and a healthful diet. His message of improving personal fitness helped bring about significant changes in the average level of exercise in the U.S. population. However, it would be wrong to conclude that the running and fitness movement energized by Jim Fixx has converted America into a nation of physical fitness enthusiasts. The National Institute on Aging reports that only 58 percent of the U.S. population pursues a regimen of cardiovascular exercise as leisure time activity, and of those people, only 26 percent do so three or more times a week as part of a long-term fitness program.

It is tempting to blame Americans for sedentary habits and not heeding the scientific evidence that supports the benefits of healthier activity levels and diet. Yet, as prosperity and labor-saving technology spreads throughout the world and sedentary work replaces physical labor, it is increasingly difficult for people to carve out time for exercise in their busy lives. To do so places a premium on health risk awareness and discipline. The "running revolution" that Jim Fixx helped to start may not have eliminated the risk of chronic illness fostered by contemporary society, but it has promoted an "exercise ethic" that now helps keep cardiovascular and other lifestyle-related diseases at bay for millions of people.

FURTHER RESOURCES

Periodicals

Maron, B. J., L. C. Poliac, and W. O. Roberts. "Risk for Sudden Cardiac Death Associated With Marathon Running." Journal of the American College of Cardiology 28 (1996): 428-431.

Mittleman, M. A., et al. "Triggering of Acute Myocardial Infarction by Heavy Exertion: Protection Against Triggering by Regular Exercise." New England Journal of Medicine 329 (1993): 1677-1683.

Thompson, P. D. "Cardiovascular Risks of Exercise: Avoiding Sudden Death and Myocardial Infarction." The Physician and Sports Medicine 29 (April 2001).

Thompson, P. D., et al. "Incidence of Death During Jogging in Rhode Island from 1975 through 1980." Journal of the American Medical Association 247 (1982): 2535-2538.