Exercise Increases Metabolic Rateser and comment back the best I can.
â??Metabolic abnormalityâ?? has provided, for many decades, a catch-all explanation for peopleâ??s failure to achieve weight loss. The best of current-day scientific studies prove, however, that abnormalities in metabolism are more myth than reality and are without basis in scientific fact. Itâ??s now well known that very few people have genetic or metabolic abnormalities that prevent them from losing weight.
The belief that abnormal metabolism is a root cause of obesity is deeply ingrained in our collective consciousness. It will probably prove impossible to dislodge this powerful, core-grabbing belief from most peopleâ??s minds, but Iâ??ll try.
Today, the metabolism evangelists have upped the ante, proclaiming their triumphal new understandings of metabolism and its science! These new-age â??expertsâ?? shout to the media, indeed to anyone whoâ??ll listen, their latest scientific gleanings from the junior varsity dietary experts and gurus who blanket the landscape of pseudo- science.
The newest â??twistâ?? actually comes directly from the fitness experts (who should know better). This theory is fodder for the marketing machine that drives an explosion of new products and programs proposed to rev- up the metabolic fires.
This new twist proclaims that adding muscle and Lean Body Mass through exercise stokes the metabolic machinery, turning-on the engines of calorie burning even while the body is at rest!
Adding muscle through exercise doesnâ??t lead to a significant increase in calorie burning at rest.
Resting muscle is not active and muscle burns few calories unless itâ??s working. Thereâ??s no free lunch.
Weâ??ve all been conditioned to think that muscle burns more calories than fat. Everyone says it, even so- called scientists. The peopleâ??s â??collective wisdomâ?? about the stratospheric rise in calorie burning that accompanies increased muscle mass is an example of hearsay. Itâ??s myth having become dogma.
Muscle at rest burns few calories: itâ??s less active than organs, which burn about 15-40 times more calories than muscle. Indeed, any large increase in muscle mass actually dilutes the increase in calorie burn that occurs when all the lean parts have increased equally in weight. Thereâ??s almost no increase in organ mass from resistance exercise, including weight training. Therefore, resting metabolic rate doesnâ??t rise as people have been taught to believe when increases in muscle mass largely represent the majority of the increase in Lean Body Mass. Weight gain, therefore, occurring because of exercise, increases muscle mass while weight gain without exercise increases all components of the Lean Body Mass as well as increases in Fat Mass.
When untrained people gain weight without exercise, their muscles and their organs increase in proportion to body size. In this scenario, the organs and muscles represent the same percentage of a 250-pound manâ??s LBM as they do in a 150-pound manâ??s LBM. In athletes, however, most of their enhanced LBM is a function of muscle mass, which increases out of proportion with increases in organ mass.
Research shows that the metabolic activity of muscle is about 1/15th-1/40th that of organs. Therefore, I calculated the metabolic rate for the â??extraâ?? muscle in a bodybuilder based upon the research I had done on bodybuilders in my laboratory. I used the metabolic rate for muscle, not the metabolic rate for both muscle and organs, to make this calculation. The difference in total 24-hour metabolism came to only 20-50 calories for the â??extraâ?? muscle in females and 44-80 calories for males.
There has been a small amount of scientific evidence showing that activity increases a muscleâ??s RMR, but most evidence clearly shows that thereâ??s no increase. The RMR in aerobically trained muscle is, at most, only ever- so-slightly higher than in bodybuilderâ??s muscles. Both rates are only slightly higher than those of inactive peopleâ??s muscles. Moving away from these observations, itâ??s clear that the difference in metabolic rate, even in big males of different fat and muscle levels, is less than 100 calories a day. For a female, this metabolic rate difference is about 25 to 50 calories each day.
A change in activity, however, can increase your calorie burn by hundreds of calories daily. Likewise, if you cut calories by decreasing your food intake, you can cut hundreds of calories, up to as many as two thousand calories daily. These are the big changes: total activity, or decreasing calorie intake, that make a real impact on weight control, not more resting muscle.
What about the calorie burn during exercise? This is physics, plain and simple. The lean 200-pounder and the fat 200-pounder both move 200 pounds. The calorie burning required by that exercise is the burning of calories to move 200 pounds. That makes the calorie burning equal. Itâ??s no more complicated than that. Bodies are generally similar in their efficiency of movement. As an example, any laboratory scientist knows that, no matter what the personâ??s body composition is, the calorie burning of riding a stationary bike is similar, regardless of bodyweight or body composition: The calorie burning of turning the flywheel is the same for each person. Although the maximum rate of calorie burning is different for trained and untrained people, the calorie burning at similar workloads is equal. Itâ??s just that the trained person can perform at a higher level than the untrained one before each maxes-out at their respective workloads, the workload being higher for the trained person.
The Differences in Metabolism Between Fat and Muscle
As a result of detailed analyses of organ and tissue contributions to metabolic rate, research shows that fat tissue has a low metabolic rate. Each pound of body fat possessed by an individual burns about 2 calories a day. The total daily calorie burn of all the fat possessed by an individual, who is 20% body fat, represents about 5% of the bodyâ??s total daily calorie burn.
Although muscle is the largest tissue in the whole body, accounting for approximately 40% of an adultâ??s bodyweight, its estimated Resting Metabolic Rate (RMR) is also low, like that of fat, at about 4.6-6.8 calories for each pound during the whole day. Because muscle tissue comprises such a large percentage of the total bodyweight, even with its low metabolic rate, the total muscle massâ??s contribution to total daily calorie burn is about 20-25% compared with 5% for fat, that is, of course, in an individual who is not fat.
Many people believe and say that, â??Muscle burns many more calories than fat.â?? Obviously, from these numbers, above, muscle burns 2-3 times more calories than fat (2 calories burned for each pound of fat and 4.6- 6.8 calories burned for each pound of muscle during the day). Itâ??s important, at this juncture, to understand that both fat and muscle at rest are low calorie burners!
In comparing two different numbers, we must always be specific and, in this case, ask 2-3 times more than what? In this case, each pound of muscle burns about 5- 6 calories compared with 2 calories for each pound of fat during the day. Fatâ??s overall daily calorie consumption is, simply, low, not making that much contribution to the total daily calorie burn of the whole body. The calorie burn by muscle at rest is, like that of fat, also, low. Yet, by virtue of its larger contribution to total bodyweight, muscle does contribute to a more significant amount of calorie burning during the day than fat. But, the addition of several pounds of â??extraâ?? muscle through exercise, particularly weight training, will make little further contribution to total daily calorie burn because of its low resting metabolic rate. Do you see how it works, by-the- numbers?
So the apparent fat burning dynamo that resting muscle is supposed to be is just not true. At rest, muscle only burns about twice as many calories as does fat.
Letâ??s contrast the calorie burn of fat and muscle with some of the bodyâ??s organs. The liver burns 90 calories per pound of liver tissue during the day. The heart and kidneys each burn 200 calories for each pound of these two tissues during the day. Obviously, these organs donâ??t weigh much, but all of these little teeny organs burn 60% of the bodyâ??s total daily calories. Muscle, as weâ??ve seen, burns 20-25% of the bodyâ??s total daily calories, far less than all of the organs combined (and muscle represents 40% of oneâ??s bodyweight).
Using a 200-pound male as an example, shows that his body has 80 pounds of muscle (40% times 200 pounds). Now, its not only â??extraâ?? muscle that burns calories, but every pound of muscle in the body as well. 40 calories per pound times 80 pounds equals 3,200 calories a day, about 1,300 more than his predicted RMR. And this is for muscle only which represents about 20-25% of the bodyâ??s total daily Resting Metabolic Rate. His body fat contributes another 60 calories to this amount, so muscle and fat burn 3,260 calories a day according to the preposterous claim. Fat calorie burning is about 5% of the total calories burned per day in the body, so that muscle and fat account, then, for 30% of the total calories burned by the body each day.
The organs (brain, liver, kidneys, lungs, spleen, etc.) account for between 60-80% of the total calories burned. Letâ??s use 70% for our calculations. The organs, therefore, would burn 10,866 calories a day. Adding this amount to those burned by muscles and fat yields an astonishingly ridiculous, unrealistic figure of total daily calorie burning of 14,126! And this is only the Resting Metabolic Rate.
Do you see how thoughtless these absurd claims are when you just take a few minutes to actually put-the- numbers-to-it? The sad tale is that every personal trainer in the country is chanting the same story.
Drop the myth that building muscle revs-up calorie burning!
Thereâ??s another myth about metabolism, as Iâ??ve said above, that circulates freely among those who think themselves knowledgeable about exercise and diet and this one is all about how exercise leads to a miraculous increase in post-exercise calorie burning thatâ??s purported to significantly contribute to bodyweight regulation. Itâ??s not true and after-exercise calorie burn makes little contribution to total daily calorie burning.
Again, I reiterate, itâ??s muscle in motion that burns calories, not muscle sitting around doing nothing. Muscle contraction uses energy and burns calories. Muscle at rest is at rest, and burns about 5 calories per pound per day.
Thanks for taking the time to read this !
Dr.Greg Elli