While it would be nice to have the sort of metabolism that lets you eat whatever you want, whenever you want, without gaining a single ounce, most of us aren't that genetically lucky. Your basal metabolic rate, or BMR, is a measure of how many calories you'd burn if you just laid in bed all day, and it's determined in part by your genetics, which can't be changed. Some other factors influencing metabolic rate are somewhat in your control, so you can boost your BMR slightly. However, you'll get more results by just increasing your overall calorie burn by getting more activity.
Factors Affecting Basal Metabolic Rate
Genetics plays a large role in your basal metabolic rate. Some people are "energy-efficient"; they burn fewer calories at rest, which was beneficial when humans had to hunt and gather every calorie they needed to survive. But in today's society, in which most people have no trouble getting the calories they need, that slow, "efficient" metabolism just makes you more likely to gain weight. Gender also plays a role in metabolism, and men tend to have a higher BMR than women.
Build Muscle Mass
One of the most effective ways to raise your BMR is to increase your muscle mass. Muscle tissue is the most metabolically active tissue in your body, and the breakdown of old protein and synthesis of new protein in your muscles accounts for roughly one-fifth of your resting metabolic rate, writes Len Kravitz, Ph.D. for the University of New Mexico. That's significantly more than the metabolic rate of fat, which contributes an average of only 5 percent to your daily resting metabolism.
As a result, gaining muscle tissue helps you pack more metabolically active lean mass onto your frame, which will increase your calorie burn, even when you're resting. To do that, you'll need to get active with strength training. Include two or three strength training workouts that work every major muscle group in your body. As a bonus, strength training helps prevent or offset muscle loss as you age, so you'll keep you basal metabolism higher for longer.
Eat Enough Calories
While severely restricting your calorie intake might seem like a good way to shed pounds fast, it can negatively affect your metabolism. You naturally reduce your metabolism when you reduce your calorie intake to resist losing weight. This was a plus to our ancient ancestors -- when food was scarce, their metabolisms would slow down to avoid starvation -- but it also means that when you cut calories too much, you'll find it harder to lose weight due to a lower metabolism.
Avoid this semi-starvation state -- and the low basal metabolic rate that comes with it -- by keeping your calorie intake to at least 1,800 calories for men and at least 1,200 calories for women.
You'll also get a slight metabolic boost by making certain food choices. Protein, for example, takes more energy to digest than carbohydrates or fat. As a result, higher-protein meals make you burn slightly more calories during digestion, which contributes to your overall calorie burn for the day. And opt for sources of carbohydrates that are high in fiber -- like beans, vegetables, fruits and whole grains. These fiber-rich carbs are harder to break down than refined cabs, like rice, so you'll burn slightly more calories during digestion.
A Better Way to Boost Calorie Burn
While basal metabolic rate does affect how easily you lose weight, it's more important to measure your active metabolic rate -- how many calories you actually burn during the day, taking into account your activity levels. When you're trying to lose weight, you'll want to eat 500 calories less than your active metabolic rate every day to lose one pound weekly; your basal metabolic rate doesn't directly factor into the equation.
The easiest way to increase your overall calorie burn is to get more activity. In addition to your strength training workouts, incorporate cardiovascular exercise -- like running, brisk walking or swimming -- into your routine. If you're already practicing cardio, improve your overall calorie burn by upping the intensity of your workouts or adding high-intensity interval training, short bursts of high intensity followed by low-intensity recovery. Not only do these training methods help you burn more calories during your workout, but you'll also increase post-exercise oxygen consumption, or EPOC, which increases your calorie burn for up to two days after your workout.