Over the past few years I’ve had the pleasure of meeting with a number healthcare providers to discuss the role and importance of exercise for their patients.  In those interactions, I’ve noted 2 common themes pop up on a pretty regular basis.

1. They believe that exercise is important for their patients
2. They are not comfortable prescribing exercise themselves, often because they worry that they may harm their patients

It’s not hard to understand why healthcare providers would feel that way.  They may have little or no training related to physical activity, and may not be physically active themselves.  And like many people, they greatly over-estimate the risks of serious adverse events as a result of physical activity.  As a result, they avoid prescribing exercise to their patients, for fear of putting them in harm’s way.

In these interactions, my main focus is typically on the safety of exercise, and why the benefits of prescribing activity programs for patients typically carries far more benefits than risk.

But what do the stats say?

Here are some stats of the risk among healthy adults from an excellent 2007 American Heart Association Position Statement on Exercise and Acute Cardiovascular Events (emphasis mine):

Malinow and colleagues²⁶ reported only 1 acute cardiovascular event per 2 897 057 person-hours of physical activity among participants at YMCA sports centers. Vander and associates²⁷ reported only 1 nonfatal and 1 fatal event per 1 124 200 and 887 526 hours, respectively, of recreational physical activity. Gibbons and colleagues²⁸ reported only 1 nonfatal event during 187 399 hours of exercise, which corresponds to maximal risk estimates of 0.3 to 2.7 and 0.6 to 6.0 events per 10 000 person-hours for men and women, respectively. Thompson and collaborators²⁹ estimated only 1 death per 396 000 person-hours of jogging or 1 death per year for every 7620 joggers. Because half of the victims had known or readily diagnosed CHD, the estimated hourly and annual rates for previously healthy individuals were 1 death per 792 000 hours and 15 260 subjects, respectively. Siscovick and colleagues⁵ estimated a similar annual rate of exercise-related cardiac arrest among previously healthy persons of 1 per 18 000 men. Both studies have wide confidence limits because the rates were calculated with only 10 (Thompson et al²⁹) and 9 (Siscovick et al⁵) exercise-related deaths.

Think about that – one death per year for every 7620 joggers per year.  That’s a 0.000013% chance of dying during your evening jog.  That’s about as safe as it can get. As I’ve highlighted above, one limitation of these studies is that it’s hard to get a precise estimate of the risk because there are so few exercise-related deaths.

From the same paper, here is the risk among those who already have some form of cardiovascular disease (emphasis mine):

The incidence of exercise-related cardiovascular complications among persons with documented CHD has been estimated by at least 5 reports with data derived from exercise-based cardiac rehabilitation programs.^34–38 Haskell³⁴ surveyed 30 cardiac rehabilitation programs in North America and reported 1 nonfatal and 1 fatal cardiovascular complication per 34 673 and 116 402 hours, respectively. The rate appears lower in contemporary exercise-based cardiac rehabilitation programs (Table 2) because an analysis of 4 reports estimates 1 cardiac arrest per 116 906 patient-hours, 1 myocardial infarction per 219 970 patient-hours, 1 fatality per 752 365 patient-hours, and 1 major complication per 81 670 patient-hours of participation.^35–38 This low fatality rate applies only to medically supervised programs that are equipped to handle emergencies because the death rate would be 6-fold higher without the successful management of cardiac arrest.^35–38 Furthermore, patients typically are medically evaluated before participation, which could decrease event rates, as could the serial surveillance provided by rehabilitation staff. Such considerations support the use of supervised exercise-based cardiac rehabilitation programs for patients after acute cardiac events.

That is also extremely low, and this is people who have already been diagnosed with heart disease.

So what about the news reports about recreational hockey players or marathoners having a heart attack?  They are the unlucky 1/7600.  When that happens it is a tragedy.  But it happens much less often than you might think.  It’s also crucial to remember that even though a bout of exercise does slightly increase your risk of a cardiac event during and immediately after exercise, it also dramatically lowers your risk of a cardiac event for the rest of the day.  So on the whole, that bout of exercise does reduce your overall risk of a cardiac event.

Also, keep in mind that those individuals may have had that cardiac event sooner, had they not been physically active.

Again, from the AHA Position Stand:

Vigorous exercise increases the risk of a cardiovascular event during or soon after exertion in both young subjects with inherited cardiovascular disease and adults with occult or diagnosed CHD. Nevertheless, no evidence suggests that the risks of physical activity outweigh the benefits for healthy subjects. Indeed, the converse appears to be true. In the Seattle study, the relative risk of cardiac arrest was greater during exercise than at rest for all levels of habitual physical activity, but the total incidence of cardiac arrest, both at rest and during exercise, decreased with increasing exercise levels.⁵

What does this mean for healthcare providers?  It means that failing to prescribe exercise is doing harm to many of their patients, because we know that the benefits of activity outweigh the risks for the vast majority of individuals.  And even for those individuals with very serious illness, low intensity exercise is still generally safe and beneficial to their health.  Going for a self-paced walk or stationary bike ride of a comfortable duration is going to be safe (and beneficial) for the VAST majority of people, irrespective of their age or health status.   Physical activity programming really needs to be seen as the standard of care for chronic disease prevention and management.

For an example of what exercise for patients with chronic conditions can look like, check out this amazing video from the Manitoba Renal Program. Believe it or not, cycling during hemodialysis is becoming the standard of care. It’s safe, and hugely beneficial for patients.

As exercise specialists continue to be integrated into the healthcare system, hopefully other healthcare providers will come to see that the benefits of exercise far outweigh the risks.