4 Ways Strength Training Can Improve Your Metabolism

Like all forms of exercise, strength training burns calories. The exact number of calories you burn depends on your bodyweight and how hard you train, but the American Council on Exercise (ACE) has estimates for different types of weight training.

A one-hour session of intense weight training burns 462 calories for a 77kg individual and 326 calories for someone who weighs 54kg. But as the intensity declines, so does the caloric burn. For example, those two people mentioned above only burn 231 and 163 calories respectively per hour of moderate-intensity weight training.

After your weight-training workout is finished, you may continue to burn extra calories throughout the day as a result of excess post-exercise oxygen consumption (EPOC). Though it's often associated with high-intensity interval training (HIIT), at least one study has suggested that resistance training can provide the benefit as well.

A February 2015 study in Research Quarterly for Exercise and Sport found that both resistance and interval training increased EPOC more than steady-state cardiovascular exercise did for moderately physically active men.

Strength training helps increase your resting metabolic rate (RMR) by increasing the amount of lean muscle on your body. Your RMR is the number of calories your body requires to perform basic functions, such as breathing, circulation and digestion.

Since lean muscle tissue is more metabolically active than fat, a body with more muscle mass will require more energy (calories) even at rest. The actual number of calories, however, is a matter of debate. Some claim that increasing muscle mass can help you to burn hundreds more calories per day, but those claims are probably exaggerated.

Studies that compare the exact caloric expenditure of fat versus muscle are rare because the measurements would be difficult to acquire with accuracy. But exercise physiologists at the University of New Mexico estimated that muscle is responsible for about 20 percent of the total number of calories you burn each day, while fat is responsible for only 5 percent.

Lastly, there's a possibility you'll burn more calories naturally with daily activity if you have a stronger, fitter body. You might do this by maintaining or increasing non-exercise activity thermogenesis (NEAT), all the movement you do throughout the day that isn't exercise.

Sometimes, when people start an exercise programme, their NEAT decreases. In fact, an October 2012 study in Obesity Reviews found that a decrease in non-exercise activity can be one of the reasons why people don't lose weight even though they exercise regularly.

But, a September 2015 study in Advances in Nutrition suggested that reduced NEAT is less likely to happen with weight training and more likely after aerobic exercise.

NEAT plays a very important role in metabolism, as it has a strong impact on the number of calories you burn each day. NEAT is also highly variable: It's responsible for 6–10 percent of your total daily calorie burn for sedentary people, and for 50 percent or more for highly active people.