I am fascinated by death. As an exercise physiologist and sports medicine specialist, much of my work focuses on why otherwise healthy people die — and particularly while they’re taking valuable steps like exercising and drinking lots of water. 

At this point, the benefits of exercising are well-known, and studies continue to shed light on exactly how it helps our bodies. For instance, exercise reduces the risk of cancer as well as cardiovascular disease. With coronavirus making us more and more conscious of preventing illnesses, research also suggests that mild to moderate exercise may protect people from dying from flu.

One group of researchers examining the Hong Kong influenza outbreak of 1998 found that those who exercised once per month to three times a week had a decreased risk of dying from the flu compared to those who did not exercise at all. This is because regular exercise has been shown to enhance immunity by getting rid of viruses faster once people become infected.

However, the start of a new year and the upcoming promise of warmer weather could lead some to overexercise and be underprepared in the outdoors. For instance, my research focuses on how healthy people die from drinking too much fluid during exercise. Water intoxication (called “hyponatremia” or low blood sodium levels) causes the brain to swell, which in turn pushes the brainstem out of the skull. As such, I also recently learned at a wilderness medical conference how healthy people can die from avalanches, drowning, high altitude sickness, carbon monoxide poisoning, rock climbing and disease.  Although morbid, the main reason this small group of physicians descended upon Sun Valley was to share stories and strategies on how to save lives while exploring the great outdoors.

Even exercising too much, too soon can take its toll if you're not careful. In the same study looking at patients during the Hong Kong influenza outbreak, researchers found that individuals who exercised “frequently” (i.e. more than four times a week), were at an increased risk of dying from the flu. This is perhaps from longer environmental exposure to the circulating virus, as gyms with poor ventilation can increase risk of infection.

All this is to say, it’s still important to exercise — but to do so safely.

We health professionals are often greedy with recommendations to exercise 30 minutes a day, five days a week, at moderate intensity. But, let’s get real. A more tangible goal is to find something — anything — that motivates people to interrupt sitting for 30 minutes per day. Even 10 minutes of exercise can yield health benefits, some studies suggest. And with the arrival of spring, now is the perfect opportunity to invigorate our senses and explore the great outdoors with a few “do’s and don’ts” to jumpstart our exercise routines:


- Find an activity that you can enjoy, and set a realistic goal.

- Let how your body feels act as a guide — if it hurts, stop.

- Find a buddy for support and camaraderie.

- Enlist in a reputable coach or exercise group, if unsure on how to start.

- If you have a history of medical problems, get checked out by a doctor.

- ANY physical activity is better than no physical activity.


- Do not exercise too much too soon (you cannot “cram” exercise after a layoff). It takes two weeks of a gradual build-up for muscle cells to adapt to exercise.

- Do not drink too much during exercise (we are not camels).

- If something hurts (10/10 on a pain rating from 0=no pain to 10=maximum pain) stop that activity until the pain subsides.

- Any sharp or stabbing pain in a specific location which lasts more than a few days (or a few minutes if it is your heart) is a warning sign to see a doctor.

- Do not exercise if you are sick, especially with fever or flu.

Mild to moderate (regular) exercise keeps us healthy and may prevent illness, such as flu. Exercise-associated deaths in otherwise healthy people are highly publicized and exceedingly rare (<1 percent). Most tragedies in otherwise healthy people are preventable. And according to the experts at the wilderness conference: heed the warning signs for avalanches (cracks in snow, whomping sounds), learn how to swim (or take a floaty), take the time to acclimatize to high altitude, don’t cook in your tent, discard climbing ropes if they are frayed (i.e. you see the core), use safety equipment as instructed, and water (of course) to drink when you are thirsty.

Most healthy people die from a lack of exercise (chronic diseases of inactivity). Healthy people die when they are ill-prepared or make bad decisions. Thus, this is not meant to scare people away from enjoying the great outdoors, but to rather encourage regular physical activity while being safe.

Tamara Hew-Butler DPM, PhD, FACSM is an Associate Professor of Exercise and Sport Science at Wayne State University.

Published on Mar 12, 2020