Study: Can physical exercise help change metabolism?

New York – Many of us remember The biggest loser, the regular regular reality show that ran for more than a decade starting in 2004, in which contestants competed hard to lose a lot of weight in a short time. One of the biggest lessons of the broadcast seemed to be that intense exercise, combined with strict calorie restriction, resulted in significant weight loss..

However, the media coverage of the contestants after years It seems to tell a different story, about gaining weight back, a slower metabolism, and the futility of trying to lose weight in the long term.

Now a new scientific analysis of the program and its effects, It was published last month in the Journal of Obesity, indicates that So many beliefs The biggest loser They could be wrong. The analysis is trying to collapse What actually happened to the participants’ metabolism and why some held out better than others. It also examines the complex role of exercise and whether staying physically active has helped runners keep their weight in check for years.

For those who may have forgotten or tried to do so, The biggest loser It aired on NBC and garnered high reviews overall for over 12 seasons. Participants competed to lose the most kilograms by using severe calorie restrictions and hours of strenuous exercise each day. In general, the “winners” get rid of tens of kilograms in a few months.

Rapid and intense weight loss has caught the attention of researcher Kevin Hall first At the National Institute of Diabetes and Digestive and Kidney Diseases, part of the US National Institutes of Health. As a Metabolic Expert, Hall knew that when people lose a lot of weight in a short time, they often send their resting metabolic rate up (Basic calories we burn every day just from being alive) in free fall. Low resting metabolic rate It may mean that we burn fewer calories overall.

It was previously thought that this effect was due in part to muscle loss during the diet.. Being a relatively active tissue, Muscle burns more calories than fat, and more muscle generally means a higher metabolic rate. So Hall wondered: Are rampant levels of exercise during The biggest loser Help dieters To maintain and maintain muscle tissue Metabolism at rest is at a high level, even when they are cutting calories?

For more than a decade, Hall and his colleagues began the first series of experiments to find out. In a 2012 study, they compared 16 men and women who lost a lot of weight by cutting calories, thanks to gastric bypass surgery, and 16 contestants from The biggest loser, who lost excessive weight exercise and diet. As expected, The shunt group lost muscle and fat, while the shunt participants lost The biggest loser She retained most of her muscle tissue and lost fat, Basically. However, their resting metabolic rate decreased by roughly the same amount, regardless of whether or not they were maintaining good muscle.

Hall said he and his colleagues were surprised by the results. Furthermore, their confusion was exacerbated when, in a 2016 study, they re-analyzed 14 of the same contestants after six years of competition and They were hoping to see that their metabolisms had recovered by then. The resting metabolic rate of most dieters rises slightly after they stop losing weight, especially if they regain a few pounds. Larger people burn more essential calories than skinny people. By that date, most runners have gained weight. However, their resting metabolism remained stubbornly slow, and they burned an average of 500 fewer calories per day than they did before they appeared on the show..

The following year, a follow-up study concluded that Physical activity has helped some runners avoid gaining weight. If they moved or exercised for about eighty minutes almost every day, they regained fewer kilos than if they exercised on a few occasions. However, his physical activity did not stimulate his metabolism at rest. Those who exercised, in fact, showed the greatest reduction in terms of resting metabolic rate.

Perplexed, Hall recently began to reconsider the studies of The biggest loser In light of a new concept about the way human metabolism works. This idea came from an influential 2012 study showing just that Very active hunters in Tanzania burn the same relative amount of calories per day as the rest of us, even though they move around a lot..

Scientists involved in this research hypothesized that tribal peoples’ bodies should automatically compensate for some of the calories they burned while foraging by reducing other physiological activities, such as growth. (Tribesians tended to be short.) from that way, Researchers believe that hunters’ bodies can maintain the total number of calories they burn each day, no matter how many miles they search for tubers and prey.. Scientists have called this idea the theory of total finite expenditure on energy.

Recognizing this research, Hall began to see potential similarities in the findings The biggest loser. So for the new analysis, he went back to reviewing his group’s data for clues about whether the runners’ metabolism behaved, in practice, like that of hunting and gathering. He’s found clues in resting metabolic rates. The figure fell early in the filming The biggest loserHall noted that when they cut back on how much they ate, their bodies understandably reduced the calories they burned to avoid starvation.

However, in later years, when the contestants went back to eating as they had done before, their metabolism remained depressed, because, as Hall concluded (and that was the key), most of them were still exercising. Paradoxically, he wrote in the new analysis, Repetitive physical activity appears to instruct your body to keep your resting metabolic rate low, so that your total daily energy expenditure can be reduced..

“It’s still just a hypothesis, but it seems to be what we’re observing” in the incoming data The biggest loser It’s an “example of the finite energy model,” Hall said.

So what can he rethink in history The biggest loser For the rest of us, if we hope to keep our weight in check? Hall said that the first and most important thing is that he indicates it Sudden and massive weight loss will generally rebound, as this strategy appears to send your resting metabolic rate more than expected, given people’s smaller body sizes. He noted that when people lose weight gradually in weight-loss experiences, their metabolic changes tend to be less severe.

The second and most puzzling thing, if you’ve lost a significant amount of weight, is in style The biggest loserExercise is likely to be an ally and something that sabotages your efforts to avoid gaining those pounds back. In Hall’s new interpretation of long-term runners’ weight management, Repetitive exercise kept their resting metabolic rate low, but also helped them avoid fat recovery. Basically, the competitors who exercised more ended up gaining less weight, although their relative metabolism was also slower.

It’s not clear exactly how and when the exercise helped them keep off the extra weight, Hall said. It is suspected that exercise affects people’s appetite in ways that possibly make them less likely to overeat, while also burning a few extra calories. He said he hopes to develop future trials to find out how exercise affects metabolism, through thick and thin.

For now, the most frequented lesson in The biggest loser it might be Losing weight in the long term, although daunting, is not useless. Yes, most of the contestants are from The biggest loser Hall said they did gain the weight back, but not necessarily every pound they lost. After six years, most of them weighed about 12 percent less than they had before participating in the program, and there was a significant difference, the most successful previous participants were those who still exercised.

Bur Gretchen Reynolds