Practice It has become a rage in many gyms across the country, as it promises to “burn” more calories in a short period of time
High-intensity interval training (HIIT) High Intensity Interval Training) has become a rage in many gyms across the country, as it promises to “burn” more calories in a short period of time, surpassing the benefits of moderate, long-term training. It is undeniable that physical exercise can promote health and improve quality of life, but to do so, it needs to be practiced well – otherwise, the harm may be greater than the benefits. An animal study showed that even for active individuals there can be bone damage. The research was carried out in Laboratory of Physiology Applied to Sport (LAFAE), from the Faculty of Applied Sciences (FCA), coordinated by professors Claudio Gobatto and Fúlvia Gobatto, and was the subject of researcher Emanuel Elias Camolese Polisel's dissertation.
LAFAE researches physiological, metabolic and molecular adaptations in different individualized training methods, both in animals and humans. In this study, two groups of mice – one more and one less active – were subjected to the same individualized high-intensity training. “We identified that high stress was generated for the bone tissue and, at least for this tissue, negative results were seen for the most active group of mice”, reveals Fúlvia. According to the researcher, sedentary people have been subjected to HIIT. “We believe that these cases require more care. Caution is needed with high-intensity efforts, even if the individual is physically active,” she pointed out.
To compare exercise levels in the two groups of animals, the Laboratory team developed larger cages than usual. “We observed that animals that live in boxes commonly used in laboratories are quieter, move little, that is, they exhibit more sedentary behavior. Those who live in larger boxes explore the environment, are more active and are able to enhance the benefits of physical exercise compared to those who are sedentary, when subjected to the same effort. There is evidence that the individual’s initial condition affects the results obtained through physical training”, explained Fúlvia.
The cages were placed on a platform with sensors. This made it possible to record all the animals' movements, day and night. “We monitored daily physical activity, carried out metabolic measurements and molecular analyzes with the animals. We observed that the most active animals showed improvements in many parameters related to quality of life, such as increased levels of calcium in the bones”, explained Fúlvia. However, according to her, the bone tissue of the most active group of mice was harmed when subjected to HIIT-type activity performed many times a week and over the long term.
Published in the magazine Scientific Reports, the study was carried out within the scope of the Postgraduate Program in Nutrition and Sports and Metabolism Sciences, in partnership with the Laboratory of Endocrine Physiology and Physical Exercise, at the Federal University of São Carlos (UFSCar), coordinated by professor Wladimir Beck. The research was supported by the São Paulo State Research Support Foundation (Fapesp).
Original article published on the Unicamp Faculty of Applied Sciences website.
