Your basal metabolic rate is a tool that trainers and nutritionists use as a starting point when developing a weight loss program. We all know what basal metabolism is – the dictionary defines it as “the amount of energy consumed by a resting organism simply in maintaining its basic functions.” The basal metabolic rate (BMR) is a measure of the energy needed to sustain the body at rest. It’s the calories you burn while doing nothing (other than presiding over your body’s basic functions such as digestion, circulation, respiration, etc., of course). It’s nature’s way of keeping you from growing infinitely larger. But how does the basal metabolic rate help us start a weight loss program?
The basal metabolic rate is a reference point used to determine our minimum daily caloric needs. We can calculate the BMR using simple arithmetic according to this formula:
Male: 66 + (6.3 x weight in pounds) + (12.9 x height in inches) – (6.8 x age in years) Female: 655 + (4.3 x weight in pounds) + (4.7 x height in inches) – (4.7 x age in years)
To illustrate, let’s figure the basal metabolic rate for a 40 year old woman who is 5’6 tall and weighs 150 pounds:
655 + (4.3 x 150) + (4.7 x 66) – (4.7 x 40) = 655 + 645 + 310 – 188 = 1,422 calories
Her basal metabolic rate is 1,422. That means this woman burns 1,422 calories just keeping her body functioning. So what does a trainer (or you) do with this information? This number represents the minimum calories you need to consume daily to sustain yourself. But what if you want to lose weight? You should just cut down on your calories, right? Wrong.
When you cut back on calories, your body reacts naturally by slowing down its calorie burning to protect itself from starvation. Even though you’re eating less, your weight stays the same. If you eat the same calories but exercise more, that should work, right? If your body works harder and doesn’t get more energy, again, it will slow down your calorie burning and your results will be negligible. So does that mean you have to eat more calories? Doesn’t that defeat the purpose? Not according to Josh Bezoni, fitness expert and co-founder of BioTrust Nutrition. He says, “Exercise increases metabolism. Eating increases metabolism. The trick is learning to balance the two so that you still create a negative calorie balance.”
Let’s say you calculate your basal metabolic rate and it allows you to burn 2000 calories a day. Knowing this, you go on a diet and begin eating 1500 calories a day which creates a 500 deficit. That would appear to be a good thing, but under-eating only decreases your metabolism.
Now let’s change a few things. Your basal metabolic rate still allows you to burn 2000 calories a day. But, instead of cutting back your calories to 1500, you start eating 300 more calories each day but you also burn 800 extra calories through exercise. The result? You get the same 500 calorie deficit (2800 calories burned – 2300 calories consumed) but you do so while increasing your metabolism through eating and exercising more. This process is especially helpful for one who has a low basal metabolic rate due to calorie restriction and a sedentary lifestyle. (By the way, a 500 calorie deficit per day yields a 1 pound weight loss per week.)
The basal metabolic rate provides a good baseline for minimum calories. Obviously, the right foods and exercise are crucial to your success. A diet of sugary foods and/or an exercise program consisting of endless walking on a treadmill will make weight loss difficult. But if you use your BMR as a starting point, you will know not to go below that level and add food and exercise accordingly to create a calorie deficit.
The basal metabolic rate gets you started. The next step is lifestyle changes. A diet high in vegetables, fruits, lean protein sources, seeds and nuts (sparingly) combined with strength training which involves both aerobic and anaerobic exercise is a good formula to follow for weight loss and good health in general. Certain sports can give you a great full body workout, as well. The best starting point in developing a weight loss plan is a calculation of your basal metabolic rate.