I have been an avid exerciser for most of my life. I love how a swim or a session at the UAMS Fitness Center makes me feel. Sometimes while exercising I get a bonus: an unexpected “ah ha” moment that provides clarity or a potential solution to some challenge that has come my way.
The science of exercise has also been a big part of my professional life. Long before I became a department chair at the University of New Mexico and then a dean here at UAMS, I began studying how exercise drives cellular adaptations. In an era of rising obesity and chronic disease, the more we know, the more we can help our patients. It has been gratifying to be involved in the pursuit of new knowledge that can vastly improve the quality of people’s lives.
Because of the work of researchers around the world, we now know many cellular mechanisms support the beneficial effects of fitness. We also know that exercise is a potent medicine. Fitness is important in its own right.
A number of scientific studies demonstrate an important benefit of fitness on mortality irrespective of body mass index (BMI). Indeed, striving for fitness appears to be more important in terms of reducing mortality than weight loss. Researchers reported in Nature Reviews Endocrinology a few years ago that this is particularly true for patients with overweight and class I obesity (BMI 30-35). Similarly, a meta-analysis reported in Progress in Cardiovascular Diseases concluded that “researchers, clinicians, and public health officials should focus on (physical activity) based interventions rather than weight loss driven approaches to reduce mortality risk.”
But what really defines “fitness?”
It’s true that fitness is generally associated with having a lower BMI and lower abdominal fat. Data clearly shows that being fit and lean is associated with improved markers for health such as having good cholesterol and glucose numbers, and the optimal health that comes with them.
Nonetheless, many studies on fitness point to the overriding importance of several key measures: your resting heart rate (RHR), your muscle mass and your muscle strength.
RHR is the number of beats your heart makes per minute while not exercising or exerting yourself. RHR varies from person to person and can be affected by many factors. You can learn more about RHR and how to determine yours on the American Heart Association (AHA) website.
RHR has been found to be an independent risk factor for mortality. It’s a good window on your heart health and can signal current or emerging health problems. We can improve our RHR through – no surprise here – exercise. Exercise really is “good medicine.”
If you would like to read more about the importance of muscle mass in reducing mortality, I recommend these articles in Underground Health Reporter, Science Daily, and the American Journal of Cardiology.