Does lean mass preserve resting metabolic rate? By Jerry Brainum

One of the major hazards of dieting, or more specifically,greatly reducing caloric intake, is a loss of lean mass.Since lean mass, mainly muscle, is the primary arbiter of resting metabolic rate, losing muscle from too stringent a diet can result in a lowered resting metabolic rate (RMR). Having a lower RMR, in turn, makes it more likley that the lost weight, and body fat will return when the diet ends. It's no wonder then, that figures show a 97% recidivism rate of people who have lost weight through dieting. In simple terms, the majority of people who lose weight from dieting alone usually regain all the lost weight, and often gain more fat than they had at the start of the diet because of the lowered resting metabolic rate that results from dieting alone.
   The obvious answer to this dilemma is to do something that will help you to retain muscle while dieting. The simple solution is to exercise while on a diet. Since weight-training is the best way to develop lean mass, lifting weights would appear to be a mandatory part of any weight-loss program. Yet, a new study suggests that even rigorous exercise will not offset the effect of dieting on the RMR. But there are a few caveats that need to be explained about this finding.
     The subjects of the study, seven men and nine women, ages 20 to 56, were all contestants on the popular TV show, The Biggest Loser. This show revolves around a competition to lose weight over a  30-week period, with those who lose the most weight being the victors in the competition. Contestants on the program are trained by professional trainers, and they workout an average of 90 minutes a day, 6 days a week. The exercise programs consist of combinations of weight-training and aerobics, with the weight-training usually being a form of circuit training, or doing several exercises in a sequence with minimal rest.  The contestants on the show, however, are encouraged to exercise an additional three hours each day. While their diets are not monitored, they are advised to consume a calorie-restricted diet containing 70% of their estimated baseline daily caloric requirements.
    In the new study, most of the weight loss in the contestants consisted of fat, with 17% coming from lean mass stores.But that lean mass also includes water and bone, so it's unclear just how much muscle the contestants lost on this regime. The contestants, despite the exercise, still showed metabolic adaptations that showed up by the sixth week, and this effect doubled by the end of the competition.Those who lost the most weight also showed the greatest level of metabolic adaptation.
     Specifically, levels of thyroid-stimulating hormone (TSH) increased by 67%, while levels of the active form of thyroid hormone, T3, dropped by 49%. T4 levels, which function as a storage form of thyroid hormone, weren't affected.These changes in active thyroid hormone accounted for the significant drop in RMR shown by the contestants. While it was previously believed that exercise would prevent this effect, it apparently did not in this group of people. The ramifications of this are that with the resultant lower RMR., the contestants, despite a large loss of bodyweight and fat, are far more likely to regain all the lost weight, and then some. In fact, this is precisely what has happened to most of the past contestants on The Biggest Loser. The salient question that arises here is: why didn't the extensive exercise prevent the drop in RMR, especially since the contestants didn't seem to lose much muscle?
    This aspect wasn't discussed by the study authors. However, I suspect that it was the speed of body composition changes that led to the significant drop in RMR shown by these people. Although they appeared to maintain lean mass through exercise, the body still may have construed the rapid loss of weight as a stress effect. This could have led to a resultant body response of lowering metabolism via the thyroid axis as means of dealing with the perceived rapid weight loss. Consider that the contestants were all obese at the start, and lost nearly half or more of their bodyfat stores. Doing so too rapidly is not a natural effect, so the body responds by turning on mechanisms to slow the weight loss.I suspect that if these people had taken longer to lose the weight, the RMR drop would not have occurred. Also, if the 17% loss of lean mass were mostly muscle, this would also account for the drop in RMR. Circuit weight-training is a good way to change body composition, but not the best way to maintain or build muscle mass.So the style of training may also have affected the outcome. The contestants may have been doing too much exercise, which is construed by the body as a stressor, leading to reduced metabolism as a way of dealing with the stress.The final aspect to consider is that rates of weight-loss on the Biggest Loser do not reflect a modest reduction in daily caloric intake. Some contestants, in their zeal to win, are probably starving themselves. This alone could result in a significant drop in RMR, and in fact, is the likley cause of what happened here, since the diets are not closely monitored.

Johannsen DL, et al. Metabolic slowing with massive weight loss despite preservation of fat-free mass.J Clin Endocrin Metab 2012: in press.

©,2012, Jerry Brainum.Any reprinting in any type of media, including electronic and foreign is expressly prohibited.

See Jerry's book at     http://www.jerrybrainum.com

Where does sucked out fat go?

Liposuction is a surgical procedure that involves the local removal of relatively small volumes of fat.When the procedure was first initiated, overenthusiastic surgeons tended to remove too much fat, resulting in a few severe side effects, including death.But over the years, liposuction, also known as "lipoplasty," has been perfected so that in the hands of a competent surgeon, it's a safe procedure.The most common areas worked on are the thighs, abdomen, and buttocks.Removing too much fat is not only dangerous, but can often lead to an unsightly dimpled look that makes you appear to have developed a new case of cellulite.In the past, some people have had as much as 50 pounds of fat removed. One of the early pioneers of liposuction, a French surgeon, screwed up the procedure on a French model, resulting in the model getting gangrene.The modern version of liposuction was also developed by a French surgeon in 1982.Today, liposuction is the most common plastic surgery procedure.
     Contrary to popular belief,liposuction is not a substitute for exercise and diet.In fact, it's suggested that obese people are not candidates for liposuction.Instead, it's more of a contouring procedure to help get rid of stubborn  fat  deposits that are said to be resistant to diet and exercise. In fact, it's still an easy way out, since exercise and diet is capable of reducing all excess fat if patience is part of the equation.
      People who are considering liposuction are often told by doctors that fat removed will not return, at least not in the area "sucked." But a recent study of women who had the procedure found that upper body fat returned within six months of the surgery. Some speculate that the sudden removal of fat triggers a compensatory effect in the body, triggering feedback mechanisms that result in a regain of lost fat. Indeed, in animals, fat that is surgically removed does return within a short time.What happens here is that fat stores in other areas of the body enlarge to compensate for the fat removed in another area.
     A recent study examined what happens to women who have had abdominal liposuction. The subjects consisted of 36 women, who two months after the surgery were randomly assigned to either an exercise group or a group that did not exercise. Those in the exercise group worked out for four months on a program that included three times a week of weight-training, followed by 30-40 minutes of aerobics done on a treadmill at an intensity level of 75% of maximum oxygen intake.The food intake didn't differ between the two groups.The study lasted six months. During that time, genes in the thighs that are related to fat regain decreased 50% only in the exercise group.Those who didn't exercise showed a compensatory gain of fat in the visceral or deep-lying fat stores in the abdomen. The subcutaneous or just under the skin fat stores, which were removed during the liposuction, didn't change. Visceral fat is considered the most dangerous of all bodyfat stores because it's linked to the onset of diabetes and cardiovascular disease.Those in the non-exercise group didn't show any compensatory fat gains in their thighs or pelvis. Note that this occurred  six months after the liposuction. Since the study authors didn't measure upper body fat, whether the women gained fat in their upper bodies wasn't known.
    The study authors think that the increase in bodyfat that happens after liposuction may be the result of a decreased energy expenditure triggered by the loss of fat. They base this on the findings of no changes in the amount of food consumed, lean mass, or leptin levels in the untrained women. The story was different in the women who exercised. The exercise totally prevented any apparent fat regain, including in the visceral fat area. Other studies have illustrated that exercise is particularly effective in reducing visceral fat stores. The exercise clearly eliminated the decreased energy expenditure that normally occurs after liposuction.The lean mass gain alone from lifting weights is enough to counter this problem.Those in the exercise group also showed beneficial changes in insulin sensitivity, as well as strength and aerobic conditioning.
     This study involved women who were not  obese, so the findings are not applicable to obese women.But obesity is considered a contraindication of liposuction, anyway. Based on these findings, it would seem to be e prudent idea for women--and men--to ensure that they engage in regular exercise that features both strength and aerobic components following liposuction procedures.

  

Want more evidence-based information on exercise science, nutrition and food supplements, ergogenic aids, and anti-aging research? Check out Applied Metabolics Newsletter at www.appliedmetabolics.com.

Benatti, F,et al. Liposuction induces a compensatory increase of visceral fat which is effectively counteracted by physical activity: A randomized trial.J Clin Endocrin Metab 2012: in press.

©,2012, Jerry Brainum.Any reprinting in any type of media, including electronic and foreign is expressly prohibited.

See Jerry's book at     http://www.jerrybrainum.com

All Men—and Women—Are Not Created Equal by Jerry Brainum

You see it all the time: Two people begin training at the same time, yet one of them seems to make gains in size and strength far more rapidly than the other. There are various explanations for the differences between hard and easy gainers. Men make faster initial muscle gains than women because men are usually larger and stronger than women. In addition, men secrete more of the anabolic hormones known to favor gains in muscular size and strength, such as testosterone. Age plays a role in how rapidly gains occur. Younger people make faster gains than older people for various reasons, especially a higher anabolic hormone level and greater recovery ability.

Back in 1954 physiologist Herbert Sheldon attempted to document the various human body-type variations. He came up with three basic types: 1) ectomorph, or thin; 2) endomorph, or fat; and 3) mesomorph, or muscular. Sheldon pointed out that humans are rarely any one exclusive type but usually are mixed, such as endo-mesomorph, or fat-muscular. The majority of bodybuilding champions are ecto-meso, or thin-muscular. Such people often start out thin, then gain muscle with training experience. When they stop training for an extended time, they revert to their dominant form. With age and metabolism changes, however, many formerly thin athletes get fat if they don’t maintain a strict diet and training schedule.

A recent study examined whether variations in gains occur in a large sample.1 The subjects included 585 people, 243 men and 342 women, ages 18 to 40. The cutoff age of 40 was set because the researchers felt that after that age the anabolic hormones needed to support muscular gains drop precipitously. In addition, none of the subjects took any drugs that might influence gains in size and strength, such as corticosteroids, which are catabolic and tend to produce losses in muscle size and strength. The subjects weren’t allowed any type of food supplement touted to boost gains, such as protein powders, creatine or pro-hormones.

The exercise consisted of one-arm preacher curls, done with the nondominant arm, for 12 weeks. Muscle gains were determined by magnetic resonance imaging, an expensive but accurate method. Strength gains were determined by baseline tests that used both isometric and dynamic exercise.
After 12 weeks individual variations in gains in muscular size and strength proved significant. Of the 585 subjects, 232 showed a 15-to-25-percent increase in cross-sectional area of muscle. Another 10 showed a gain of 40 percent, while 36 subjects gained only 5 percent muscle size. While the expected finding was that men would make greater size gains than women because of higher levels of testosterone, when relative size differences were taken into account, the women proved just as liable to gain muscle size as the men.

Nor did age affect the rate of muscle gains, since the older subjects made gains similar to those of their younger counterparts. The authors attributed that to a fairly stable level of testosterone secretion in the older subjects, noting that the hormone doesn’t drop enough to blunt muscle gains until about age 60; some would disagree.

As for strength, 232 subjects increased their one-rep maximum by 40 to 60 percent. That means their ability to lift a weight for one rep improved by 40 to 60 percent. Another 36 subjects made gains of 100 percent in one-rep max, while 12 subjects gained less than 5 percent. Similar figures held for gains in isometric strength, although one subject made gains of 150 percent in that area.
Women showed greater variability in dynamic strength, or the type of lifting most often done in bodybuilding workouts—eccentric and concentric muscle contractions. The greater variability could be explained by women’s naturally greater joint flexibility. In addition, the women were less skilled on average than the men in performing preacher curls at the start of the study, and with continued skill acquisition some might have made better gains than others. In total, the women made better strength gains than the men. Thus, the men made better gains in muscle size, while the women proved superior in strength gains, likely because they were much weaker at the start of the study.

The study shows that most people make significant gains in muscle size and strength when they begin regular training. Men show faster muscle size gains on average, while women may get stronger faster than men. The unanswered question of the study is why the variations in the gains occurred. Why did one trainee show a 40 percent muscle-size gain after 12 weeks of training, while another had only a 5 percent gain?

Factors not discussed in the study could explain the wide variations: diet, how intensely you train, how much rest you get, and so on. Also, genetic factors certainly play a dominant role in who makes the fastest gains. Perhaps some people have genes that favor muscle gains that are activated when they begin training. Somebody else may not produce as much myostatin, a protein that inhibits muscular growth, or may produce other proteins that block the activity of myostatin, which would favor rapid gains in size and strength. Although the study suggested that testosterone didn’t play a major role in the gains made by the male subjects, other studies show that higher initial levels of testosterone and other anabolic hormones favor more rapid muscle gains.

1 Hubal, M.J., et al. (2005). Variability in muscle size and strength gain after unilateral resistance training. Med Sci Sports Exer. 37:964-72.

©,2012, Jerry Brainum.Any reprinting in any type of media, including electronic and foreign is expressly prohibited.


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Age-related Changes In muscle protein synthesis by Jerry Brainum

Several studies have shown that older people experience a decreased rate of muscle protein synthesis. A study presented at the ’06 ACSM meeting compared the changes in plasma amino acid concentrations and muscle protein synthesis rates in healthy young and older subjects following a meal that included four ounces of lean beef.¹

The younger subjects’ average age was 28; the older subjects, 69. The authors calculated the rate of muscle protein synthesis immediately following and for five hours after the beef meal. Eating beef increased MPS rates in both the young (27.9 percent) and older (29.1 percent) subjects. The plasma amino acid levels peaked about 100 minutes after the meal in both groups. The magnitude of increase in blood amino acid levels was higher in the older group because of smaller blood volume and lower lean mass.

The study shows the fate of ingested food protein in both young and older people, which proved to be similar. Another useful observation involved the peak amino acid level, which occurred about 1 1/2 hours after subjects in both groups ate the meal.

Another study presented at the meeting involved providing carbohydrate with or without protein and free leucine (a branched-chain amino acid) to young and older groups, again to compare rates of protein balance and muscle protein synthesis.² As expected, insulin levels rose higher in both groups when they got a carb-protein-and-leucine supplement. Carbs alone provided no increases in MPS. The researchers’ conclusion was that combining carbs, protein and leucine brought about similar rates of upgraded MPS in both the young and old.

References

¹ Paddon-Jones, D., et al. (2006). Age specific changes in protein synthesis and plasma amino acid profiles following intact protein ingestion. Med Sci Sports Exerc. 38:S113.

² Koopman, R.,et al. (2006). Co-ingestion of protein and leucine stimulates muscle protein synthesis in young and elderly men. Med Sci Sports Exer. 38:S113.

©,2012, Jerry Brainum.Any reprinting in any type of media, including electronic and foreign is expressly prohibited

Lose Muscle With Aerobics? by Jerry Brainum

In bodybuilding, it’s axiomatic that doing aerobics promotes loss of muscle. The theory is that aerobic exercise depresses muscle protein synthesis—or maybe it lowers anabolic hormones, such as testosterone. Like a lot of bodybuilding axioms, however, it ain’t necessarily so.

In fact, one study found that subjects who did strenuous aerobics for an hour over the course of three days had levels of muscle protein synthesis similar to those that occur after weight training. Based on that unexpected finding, a new study was designed to measure skeletal muscle breakdown in the thighs after an hour of strenuous one-legged aerobic exercise.

The study, which featured five healthy young men, was reported at the 2006 ACSM meeting. The muscle protein breakdown was measured at rest, and at six, 24, 48 and 72 hours after the exercise. Muscle protein breakdown was determined by the excretion of 3-methylhistidine, a substance produced only in contractile muscle proteins.

      The results revealed no difference in muscle protein breakdown at any point after the exercise. On the other hand, as in past studies, muscle protein synthesis increased, just as it does after weight training. The authors think that happened to offset the breakdown that would normally occur after strenuous exercise.
    A practical application of those findings is that doing higher intensity aerobics, such as interval training, characterized by alternating periods of high and low intensity, may not only produce greater cardiovascular benefits than the usual steady-state aerobics but also blunt muscle protein loss.

¹ Haus, J.M., et al. (2006). The effect of strenuous aerobic exercise on skeletal muscle myofibrillar proteolysis in humans. Med Sci Sports Exerc. 38:S549

©,2012, Jerry Brainum.Any reprinting in any type of media, including electronic and foreign is expressly prohibited.