Can You Speed Up Metabolism By Running?

Running lore has it that, if you run frequently and long, your body will adjust its metabolism so that you actually burn more calories when not exercising than you did before you took up running. While not exactly true, there is useful fact in the tale. Learn the rest of the story, and you can capitalize on the weight loss facets of your training schedule or rethink your training to meet your body mass goals.

Metabolism

By speeding up the metabolism, most people mean speeding up the metabolic rate. Organs and physical processes like breathing require energy. Remove all sympathetic nervous system stimulation, fast until the digestive system is inactive and place a body in a temperate environment, and the amount of energy it uses is called the basal metabolic rate (BMR). Add digestion, thinking and a few meals, but no activity, and you have the body at its resting metabolic rate (RMR).

Measuring

It isn't hard to figure out your RMR to an acceptable degree of accuracy without sophisticated equipment and the help of a researcher. Use one of the online RMR calculators or a reputable equation, such as this, based on the Mifflin (et al) study "A New Predictive Equation for Resting Energy Expenditure in Healthy Individuals:" RMR = {[50 X Weight (pounds)/11] + [15.875 x Height (inches)]} - [5 x Age (years)] + [+ 5 (male) or - 161 (female)].
For example, for a 30-year old woman,130 pounds and 5 feet, 4 inches: RMR = {[50 X 130/11] + [15.875 x 64]} - [5 x 30] + [- 161 (female)] = {[590.90 + 1016] - [300]} + [- 161] = 1145.9 kcal per day.

Factors

Large people burn more calories than small people. So do those with a higher muscle-to-fat tissue ratio. This is why a 130 lb. man expends more energy per day than a 130 lb. woman: on average, the female body carries more fat tissue than the male. The proportion of muscle tissue tends to decline with age. This suggests that working out to maintain a healthy proportion of fat to muscle in your body is an effective way to achieve a good metabolic rate.

Possibilities

It's easy to believe that fit people burn more calories, even while resting, than do sedentary people. This may be true, but research on the topic is ambivalent. C.E. Broeder and colleagues, in a study published in 1992 in "American Journal of Clinical Nutrition," conclude that RMR may increase for some hours after aerobic exercise. Other researchers disagree.

Unequivocal Accelerants

Strength training increases muscle mass, so this discipline is an excellent way to affect your metabolic rate. High-intensity interval training--going all out for short bursts of time--seems to improve the body's ability to burn fat. Perry et al state unequivocally in a 2008 paper, "This study demonstrated that [...] repeated high-intensity exercise [...] is a powerful method to increase [...] capacities to oxidize fat."