Why does exercise make you stress-resistant?
Researchers at Princeton University recently made a remarkable discovery about the brain. They examined the brains of rats, and found that rats who constantly exercise, tolerate stress much more easily than lazy rats. Scientists already know that exercise stimulates the creation of new brain cells (neurons, nerve cells), but only now it is becoming clear that new cells are functionally different from other brain cells.
In an experiment, preliminary results of which were presented last month at the annual meeting of the Society for Brain Research in Chicago, scientists allowed one group of rats to exercise. Another group was deprived of this opportunity. After a while, all the rats were expected to swim in cold water, which they do not like very much. After that, scientists began to study the brain of animals. They found that the stress of bathing activates nerve cells in all areas of the brain. (Researchers can even tell which neurons were fired because the cells release a special protein in response to stress.) But in trained rats, young brain cells that (according to scientists) appeared and grew as a result of increased training, “stress protein” isolated in a smaller amount. The trained rats looked calmer than the rats in the “lazy” group. “Training-born cells,” the researchers think, “are already being built with a margin of safety .” Apparently, the rats, through exercise, have created a biochemically calm brain.
For many years, both in everyday life and in academia, it has been believed that exercise and exercise improves mood. But it was unclear exactly how exercise might affect mood and anxiety . Now, thanks to new research methods, and thanks to the latest advances in biochemistry and genetics, scientists have yet to understand how exercise restructures our brains, making it stress-resistant. For example, a group of researchers that sought to debunk the myth of serotonin as the “hormone of happiness” put rats in a state of helplessness and anxiety. All of these rats had elevated serotonin levels. But here’s what’s interesting: rats that had been running for several weeks before showed a lower degree of anxiety, and their serotonin levels were not as strong as in the rest of the experimental subjects. Another group of researchers studied the effect of moderate exercise on oxidative stress in cells. Anxiety in rodents and humans is accompanied by excessive oxygen starvation of cells, as a result of which cells (including brain cells) can die. Moderate exercise reduces the effects of oxygen deprivation. In an experiment conducted by researchers at the University of Houston, rats were injected with drugs that chemically caused oxygen deprivation in all cells of the body. After that, the rats were transferred to a new, unknown to them, environment. Those rats that did physical exercise, unlike their lazy counterparts, did not hide in panic in dark corners, but began to explore new territory, although they were also scared. “An interesting picture emerges – exercise and stress prepares and trains brain cells, and they are experienced in real stress and they are already experienced and can better cope with critical situations,” says Michael Hopkins, a graduate student at the Laboratory for the Neurobiology of Memory and Learning in Dartmouth. “It’s really amazing that you can now link exercise and stress tolerance for good reason.” Resistance to stress does not appear overnight. But it will appear, and all scientists agree with this. For example, in an experiment by the University of Colorado, rats that were involved in sports for only three weeks did not show themselves to be stress-resistant. But those rats that ran for six weeks – showed. “Something happened in those three weeks,” says Dr. Benjamin Greenwood, a research fellow at the University of Colorado. He also added that “it is not yet clear how to translate” this rate of six weeks from rat time to human time . Maybe we need more time, maybe less. In addition, no one has yet said what loads are optimal for the rapid development of stress resistance. But one thing remains absolutely clear – we must continue training. Continue running, pedaling, swimming (so far in the studies, animals have only done aerobic exercise). You may not feel the reduction in stress after your first run. But according to Dr. Greenwood, biochemical processes will already start, and changes in the cellular structure of the body will be profound.