Resistance training also helps with weight control. You’ve probably heard when you have more muscle you burn more calories even at rest because muscle is more metabolically active than fat tissue. In other words, if you replace 8 pounds of fat with 8 pounds of muscle, you burn more calories throughout the day even if you do the same activities. How much impact does muscle tissue have on your metabolism?
Does Having More Muscle Increase Your Metabolic Rate?
In one study carried out in men and women over the age of 55, participants took part in 3 months of resistance training. During the 12 week study, they gained an average of 3 pounds of muscle and lost an average of 4 pounds of body fat. When researchers compared their energy expenditure, before and after resistance training, their resting metabolic rate had increased by 15%. Not bad!
Not all studies show this degree of increase in resting metabolic rate as a result of building more muscle. According to one study, an additional pound of muscle gained through resistance training burns as little as 6 additional calories daily. Other research shows a pound of muscle could burn as much as 50 extra calories a day. A bit of a discrepancy! Although it’s not clear exactly how much having more muscle boosts energy expenditure, it does appear to make a difference. When you consider men have resting metabolic rates that are around 3% higher than women, differences in body composition (lean muscle versus fat) probably account for a substantial portion of this difference.
Resistance Training and EPOC
Resistance training has beneficial effects on energy consumption and fat-burning in another way. When you lift heavy weights or do high-intensity exercise, it creates an “afterburn” effect. For a variable period of time, at least several hours, your metabolic rate is increased due to the intensity of your training. That’s because your body needs to expend more energy to return your core body temperature to normal, remove lactate, repay the oxygen debt, etc.
So-called metabolic resistance training where you lift challenging weights with minimal rest periods between sets is a way to get the afterburn effect. This keeps your metabolism revved up for hours even after you’ve finished. Ever finished a workout, taken a shower and noticed you’re still sweating? You’re feeling the effects of the afterburn and are sweating as your body works to return your core body temperature to normal. You don’t get this benefit when you do moderate-intensity, steady-state exercise.
How can you maximize the afterburn when resistance training? You’ll get more of a metabolic effect if you focus on large muscle groups, compound exercises and minimal rest between sets. Isolation exercises that only work a single muscle group, especially those in the upper body, won’t have the same effect.
Resistance Training Helps Prevent Age-Related Sarcopenia
There’s another way resistance training benefits your metabolism. Even if you manage to maintain your weight without resistance training, it becomes more difficult to do this with age. If you’re 55, you may weigh the same as you did at 30, but some of the lean tissue (muscle) you had at 30 has decreased. You lose between 3 to 5% of your muscle mass each decade after 30. In addition, muscle loss speeds up after menopause. If you still weigh the same, some of that muscle has been replaced with fat. That impacts your daily energy expenditure and makes it easier to gain weight. Resistance training reduces the amount of muscle tissue you lose as you age. It helps to protect you to some degree against the metabolic slowdown that comes with age. This makes it easier to control your weight.
The Bottom Line?
Each pound of muscle you build increases the number of calories you burn on a daily basis. How much it does this is debatable since studies aren’t consistent. But resistance training benefits your metabolism in other ways as well. Metabolic resistance training increases energy expenditure for hours after you’ve completed a workout. Plus, resistance training to build muscle helps protect against the slowdown in metabolism that comes with age. That’s something we all want to avoid!
If you want the benefits, intensity counts. Isolation exercises using lighter weights that you can lift 15 or 20 times won’t give you a significant afterburn. Compound exercises with heavy weights and only enough rest so you can maintain intensity, will maximize energy expenditure after your workout is over.
References:
Am J Clin Nutr August 1994 vol. 60 no. 2 167-175.
Web MD. “Muscle Loss with Aging”
Chantal A. Vella, Ph.D. & Len Kravitz, Ph.D. “Exercise After-Burn: Research Update”
Journal of Strength and Conditioning Research 23 (2): 611-8. (2009)
ISRN Physiology. Volume 2013 (2013), Article ID 825026, 10 pages
Harvard School of Public Health. “Weight training associated with reduced risk of type 2 diabetes”
Related Articles By Cathe:
Does Strength-Training Really Boost Your Metabolism?
Is Muscle Loss the Only Reason Your Metabolism Slows with Age?
5 Most Important Factors That Affect Total Daily Energy Expenditure
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STS Strength 90 Day Workout Program
All of Cathe’s Strength & Toning Workout DVDs
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Great post. I kind of overlooked resistance training and focused more on aerobic exercises but after reading this I will definately include more resistance workouts in my program. Thanks.