As much as I might try to fight it, fitness has a pretty big mathematical component. Athletes will often use formulas to predict their progress and calculate what weight they should be working with or how many miles they should be clocking on a given week. More frequently, though, health-minded individuals will use any number of calculators and tools to gain a deeper understanding of their “ideal” diet and metabolism.
When taking on this particular task, you’re going to come up against all sorts of jargon–most of which is pretty self-explanatory. Some of these terms, however, are commonly misused and misunderstood. As result, you may deal with feelings of confusion and frustration when trying to calculate your caloric needs. Perhaps the most problematic of these terms is “resting metabolic rate.” What, exactly does this refer to? Why does it matter? Can you change your resting metabolic rate?
What It Is
As its name suggests, resting metabolic rate (RMR) is that amount of calories that you burn when you’re at rest. These calories produce the energy you need to simply stay alive, supporting your heart, lungs, and other more subtle bodily systems while you’re sitting on the couch doing nothing.
Although the term RMR is often used interchangeable with basal metabolic rate (BMR), there are some slight differences. Specifically, BMR measurements are taken while an individual is sleeping while RMR is not. Practically speaking, then, BMR will provide you with a more accurate understanding of your metabolic health but does require specialized equipment, and it’s not as accessible as RMR.
Why It Matters
But why should you care about your RMR? What possible use could this number have? Because it gives you an estimate of how many calories you need to support your basic biological functions, RMR is the starting point for figuring our how many calories you need to eat to reach your fitness goals.
Once you have this number, you can account for the amount calories that you need to support your activity. From there, you can add or subtract depending on whether you hope to gain or lose weight.
Your RMR, then, is the basis for all other metabolic calculations you might be tackling.
Since RMR represents the number of calories that you burn during inactivity, it would make sense to try to increase it. After all, burning more calories while doing nothing is sort of the fitness dream. And, to that end, there are lots of theories about how to accomplish this goal.
Unfortunately, none of them really hold up to scientific scrutiny. While things like EPOC and strength training can both have modest effects on your RMR, you would have to make enormous–and largely unrealistic–changes to your body composition in order for these shifts to be meaningful.
So while understanding your RMR will definitely help you to plan your diet more effectively, trying to change your metabolism to affect weight loss isn’t really the best use of your time.
by Jonathan Thompson
Jonathan Thompson is a Certified Personal Trainer and Nutrition Specialist whose health and fitness articles are scattered all over the internet. Jonathan has also written for several wellness periodicals, including IgNite magazine and has recently published his first fitness book – Weighted Vest Workouts