Another great lecture that I attended at the American College of Sports Medicine conferene was on your metabolism. Liz Applegate, Ph.D., FACSM, director of sports nutrition at the University of California at Davis, says resting metabolic rate – the amount of calories the body burns in a resting state to keep internal organs operating – can be improved through lifestyle changes.
The easiest way, she says, to calculate metabolic rate is to figure 10 calories burned for every pound of body weight for women, and 11 calories for every pound of body weight for men. For instance, a 130-pound woman has an approximate resting metabolic rate of 1,300 calories per day.
However, Applegate says certain key factors affect the exact metabolic rate for individuals. These factors can be altered in your favor to stimulate more calorie burn – and, in turn, weight loss.
Body composition
How it affects metabolism: Muscles, the workhorses of the body, use more calories to operate than fat. So, the more fat you have, the fewer calories your body will naturally burn.
How you can change it: Replace that fat with muscle. Strength training creates lean muscle mass.
Age
How it affects metabolism: Resting metabolic rate generally drops 2 to 3 percent every decade after age 20, typically due to a loss of lean mass.
How you can change it: Stop the loss of lean mass through strength training.
Hormones
How they affect metabolism: Thyroid hormones have the biggest impact on resting metabolic rate because they tell cells how much oxygen to use, or how many calories to burn. Thyroid activity typically slows after age 40 in women, accounting for some women’s mid-life weight gain.
How you can change it: In general, you can’t. Applegate says not to buy the hype about supplements that claim to increase thyroid activity. Focus your efforts on other factors that impact metabolic rate.
Calorie restriction
How it affects metabolism: Although cutting an extreme amount of calories from your daily diet seems like the pathway to quick weight loss, self-starvation actually slows metabolic rate down significantly.
How you can change it: Don’t send signals to the body to conserve calories by detoxing or fasting. According to ACSM guidelines, women should eat at least 1,200 calories per day, and men should eat at least 1,800. Small, sensible deficits lead to healthy, long-term weight loss.
Diet
How it affects metabolism: Certain dietary components – and the right combination of them – increase metabolic rate.
How you can change it: Make sure your diet has the right balance. Proteins take more effort – i.e., calories – for the body to process. Applegate recommends eating 18 to 20 percent of the day’s total calories in lean proteins. Also, consume more fiber, which may slightly block caloric absorption and keep you feeling full.
Applegate cautions that while implementing no single factor listed above will make a noticeable change in resting metabolic rate, practicing several can. "Doing just one of these things might only lead to 60 or so more calories burned per day,” she said. “But when you start factoring in several of these modifications, they can really add up and make a difference.”