Thoughts about “Fitness”
What do we mean when we talk about fitness? It seems that the word “fitness” has come to be synonymous with thinness in our culture, and that is not accurate. The definition of cardiorespiratory fitness (CRF) is basically: how good are your heart and lungs at getting oxygen to your muscles when you are using them? This used to be measured by having a person walk on a treadmill at a comfortable pace, then the treadmill increased in incline by a degree each minute until the person was too out of breath to continue. Other, more detailed tests are used now, but the idea is the same. CRF is a much more accurate predictor of overall health than body size.
Just because someone is thin does not mean they are fit, nor does being heavier mean a person is not fit. A thin person might get out of breath climbing one flight of stairs and a heavy person might be able to hike in rugged terrain comfortably for an hour. Yet, when we see the word “fitness” used in general media, it is often used incorrectly, to mean thinness. Contrary to general opinion, we cannot determine a person’s level of fitness simply by looking at them.
As an example, I recently read an article in a local publication about several people who were starting a “fitness journey.” When they were asked about what it meant to “get fit,” the answers were mostly about appearance, such as fitting into clothes that were purchased several years ago, or feeling good about what they saw in the mirror. The article made a point of saying that the outcome measures were “not only the number on the scale” but also BMI (which is totally about the number on the scale) skeletal muscle mass, percentage of body fat and photos (which are totally about appearance.) Nothing in the article referred to actual cardiorespiratory fitness.
Diet culture teaches us that the best way to improve ourselves, our health and our well-being is to lose weight, yet we know that weight loss attempts are doomed to failure and contribute to poorer physical and mental health. At the same time, even a modest increase in physical activity in someone who is sedentary can improve CRF. If we truly are interested in improved health, we need to change the focus from appearance to actual fitness.*
You can find more on diet culture and how it damages us in my book, Thrive at Any Weight.
*understanding that health is not a measure of worth, is not entirely in our control, and means different things to different people.