The Unexpected Exercise That Reduces Body Fat And That You
Nutrition

The unexpected exercise that reduces body fat and that you often avoid

Lifting weights not only serves to show off bigger muscles, recent research claims that it also helps burn fat.

A woman stopping to drink water and a man lifting a dumbbell.

Weight loss in general, and fat loss in particular, is one of the goals most pursued by gym customers in Spain. However, most of them continue to attach great importance to aerobic-type sports —such as running, swimming or cycling— and ignore the need to perform step lifting exercises, or anaerobics.

This last type of training is crucial for fat loss, and now a new study published in FASEB Journal clarify why. According to this study, conducted by the University of Kentucky College of Medicine and Health Sciences, weight-bearing exercises regulate fat cell metabolism at the molecular level.

It has always been thought that weight training only seeks to strengthen and develop muscles, but this is not entirely true. The weight training also renews body fat: this is due to the fact that muscle tissue has a more active metabolism than others —such as adipocytes or fat cells—, that is, it has a higher energy expenditure both during activity and at rest. Therefore, the more proportion of muscle we have, the easier it will be for us to burn calories.

Muscle-Fat Conversation

However, fat burning cannot be fully explained by this theory. For years, various investigations have suggested that muscle cells and fat cells communicate in some way after training. And, in fact, for the last decade this idea that cells and tissues communicate with each other has become widely accepted, although it is a complex communication. The release of hormones and other proteins after exercise, traveling through the bloodstream and various organs, would give rise to a process known as cellular crosstalk.

Cells and tissues can also pump out tiny bubbles, or vesicles, during this crosstalk, or communication. Previously these vesicles were seen as cellular bits of useless “garbage”. However, it is now known that they are also a medium of communication between cells, since they contain genetic material and healthy molecules, among other substances.

In previous studies it would have been seen that the aerobic exercise, like running for example, enhances the release of this type of vesicles from muscle tissue. But there is little evidence whether this process also occurs after a weightlifting training.

burn fat with weights

In this case, the researchers responsible for the study decided examine mouse cells: First, they artificially disabled several of the leg muscles of healthy rodents, leaving only one muscle to support exercise. Said muscle hypertrophied, increasing in size rapidly, more rapidly than usual.

Before and after the process, the researchers analyzed blood and tissues of mice and searched for the aforementioned vesicles and other communication molecules in the tissues. According to their findings, prior to training, the mice’s leg muscles contained a large amount of miR-1, a piece of genetic material that regulates muscle growth. In untrained muscles, miR-1 slows muscle growth.

However, after the mice exercised, the mice’s leg muscles appeared to have depleted miR-1. At the same time, vesicles packed with this genetic material were detected in the rodents’ blood, and the same material was also detected in nearby fat tissue: the muscle cells had packaged these bits of genetic material, which slows muscle growth, and they had sent it to the fat cells, allowing accelerated muscle hypertrophy.

For its part, in fat cells, miR-1 appears to accelerate the breakdown of fat into fatty acids, which can then be used as fuel by other cells, thus reducing total body fat stores.

muscle mass

Essentially, the weight training would have a double function at the molecular level: increase the size of muscle cells, which in turn would send genetic material to fat cells, ordering them to break down fat that in turn will be used as fuel, thus closing the cycle.

Since studying mice is not the same as studying people, the researchers added one more experiment to your research: blood and muscle tissue samples were taken from men and women healthy subjects who had done a single intense lower-body workout.

Again, it was confirmed that miR-1 levels in the volunteers’ muscles were reduced after weight training, and the number of miR-1-packed vesicles in the bloodstream spiked. Just like in mice.

Even so, It should be noted that this study involved mainly mice and not humans.; only this last final comparison was made in our species, but not the whole experiment. Thus, it is not possible to know how often or how intensely a human should train to maximize vesicle production and subsequent fat burning. But the results are a good reminder, say the authors, that muscle mass is vitally important when it comes to metabolic health.