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This column has never been an opinion piece since I try to present some of the science behind physiological adaptation. On the surface this particular column may appear to be opinion, but notably it is still based on scientific evidence. The impetus for this column is the discussion about how safe Fort Collins roads are for cyclists. I could talk about how safe I think Fort Collins roads are compared to the other cities, and often cycling friendly cities, I have lived. It is not Copenhagen (where I spent two years) but it is the most cycling friendly US city I have lived in. If I wrote a column about my perceived safety of Fort Collins roads, it would just be an opinion. Instead, the column will talk about riding versus being sedentary. Admittedly, there is a lot between these two extremes, but it is my favorite way to stay active and I write the column.

The Table shows the top 10 causes of death in the United States. Number four on the list is accidents, of which bike accidents would be a very small fraction of total accidents (I don’t have the exact number). Looking at the remainder of the list, 89.4% are chronic diseases, which means they are in part preventable. The CDC estimates that 40% of these deaths (actually including accidents) are preventable. What is the one thing that is known to prevent all of these chronic diseases? Exercise. Therefore, if I was a gambling person, the chance of being killed by an accident is far less than being killed by a chronic disease. The one well established way to avoid chronic disease is exercise. To me, the chance of being hurt on my bike is far less a concern to me then living the last 20-40 years of my life battling a single or multiple chronic diseases.

I study aging. Aging is the biggest risk factor for the majority of chronic diseases. Therefore, by slowing the aging process, you simultaneously decrease the chances of cancer, stroke, dementia, arthritis, heart disease, diabetes, Alzheimer’s, Parkinson’s, osteoporosis, and other chronic conditions. The best way to slow the aging process is with lifelong physical activity. The data are expansive, but I will reference two studies that are think are particularly effective. A group at Stanford followed a group from a local running club and age matched controls over 20 years. By the end of the study, those in the running group had a mean disability score that was equal to the control group 14 years younger. Said another way, the runners were essentially 14 years younger than the controls.
The second study I would like to talk about was a recent study examining a group of lifelong exercisers from Sweden. This group that was studied was unique in that many of them were elite athletes, even Olympic champions, and continued to exercise the remainder of their lives. At the time these athletes were examined, they have a VO2max comparable to non-endurance trained men 40 years their junior. Although many may know that VO2max is a variable associated with endurance exercise potential, it is also a powerful predictor (actually one of he most powerful predictors) of morbidity and mortality. Think of this as having the physiology of someone 40 years younger than you.

The next time you watch your favorite hospital show (ER, Grey’s Anatomy, House, etc.) think about what these shows would be like if they really featured what killed people in the United States. Think about a television program that showed a bunch of people with heart disease, cancer and diabetes. No one would watch, right? I could go on and on about the power of exercise to prevent chronic disease. How it does so is the basis of many scientific studies. It is actually generally recognized that exercise is a panacea. The trick is getting people to do it. For those of your reading this column, exercise is a part of your life. If cycling is how you do it, you should continue to do so. Exercise prevents chronic disease, and chronic disease is what kills those in the United States. Accidents are a small part of what kills people. By no stretch of the imagination am I saying that there are not dangers involved with what we do, and the chance of injuries and sever injuries are there. However, I will continue to play the odds and prevent a life of chronic disease and the decreased quality of life and early death versus an accident.


Table. Number of deaths for leading causes of death in the US:
Heart disease: 611,105
Cancer: 584,881
Chronic lower respiratory diseases: 149,205
Accidents (unintentional injuries): 130,557
Stroke (cerebrovascular diseases): 128,978
Alzheimer’s disease: 84,767
Diabetes: 75,578
Influenza and Pneumonia: 56,979
Nephritis, nephrotic syndrome, and nephrosis: 47,112
Intentional self-harm (suicide): 41,149

Reduced disability and mortality among aging runners: a 21-year longitudinal study.
Chakravarty EF1, Hubert HB, Lingala VB, Fries JF. Arch Intern Med. 2008 Aug 11;168(15):1638-46.

New records in aerobic power among octogenarian lifelong endurance athletes.
Trappe S, Hayes E, Galpin A, Kaminsky L, Jemiolo B, Fink W, Trappe T, Jansson A, Gustafsson T, Tesch P. J Appl Physiol. 2013 Jan 1;114(1):3-10.