Physical activity puts molecules into circulation which preside, with their regulatory function, over vital mechanisms, from immunity to inflammation, to be exploited in a preventive and therapeutic key. Meanwhile, research reveals surprising powers of tissue regeneration. That’s why sport goes far beyond physical efficiency: it’s a fun way, available to everyone, cheap but above all powerful to protect our health. It’s up to us to fight the evolutionary ballast that drives us to overeat and sedentary lifestyle
VITA magazine of July is dedicated to sport and its social function, presented here and which you can download Who. But why is sport good for you? Training the body means improving physical efficiency, therefore muscle strength, cardiorespiratory efficiency and body composition. Yet, this is only part of the story. In fact, initially all aimed at obtaining knowledge useful for improving the performance of professional athletes, sport physiology has revealed the complex biochemical mechanisms through which physical activity promotes the health of the whole organism, brain included, regulating some vital processes. Knowing them in depth would allow us to identify molecules capable of reproducing the almost pharmacological effect of sport, thus giving all the benefits of physical activity to those who, not out of laziness, but due to illness or old age, are no longer able to move. Their name is exercise-mimetic drugs.
“In the last fifteen years, we have discovered a great deal, including that physical activity not only guarantees the correct functioning of the body but promotes tissue regeneration,” he explains Antonio Paoli, professor of Exercise and Sport Sciences at the Department of Biomedical Sciences of the University of Padua, where he directs the Laboratory of Nutrition and Exercise Physiology. Paoli, who is past president of the Italian society of motor and sports sciences Sismes and of the European sport nutrition society Esns, is back from the European congress of the European college of sport Ecss 2023.
A forge of precious molecules
«Skeletal muscle contraction and the mechanical stress produced by physical activity promote the secretion of molecules and proteins that come pourthe in the circulatory stream blood» Paoli explains. These start a cascade of very complex signals, thus regulating functions of various organs, including neurogenesis, angiogenesis, synthesis of new mitochondria, oxidation of fatty acids, regulation of inflammation. Furthermore, «physical activity increases the levels of brain neurotrophic factor (Bdnf), neuroprotective protein that stimulates neuroplasticity and neurogenesis, mediator of the positive effects of sport on memory and cognition; gets better the glucose transport capacity and the use of triglycerides and at the liver level it helps to keep fat accumulation under control» explains Paoli. “In the end, reduces inflammationdespite its initial growth in acute functional adaptation to the training stimulus».
“Let’s go take a walk”
These physiological responses are triggered by both anaerobic power training and aerobic resistance training: «National and international guidelines, which did not provide for work with overloads, today indicate that should be entered two sessions per week of strength training» says Paoli, admonishing that, in any case, it is not a question of limiting oneself to taking a stroll: «Moving is not enough! We need to overcome that critical threshold beyond which exercise can perform its crucial functions. To establish the minimum level appropriate to each, e consequently modulate the frequency, intensity, time and type of activity without risk of injury, even in the case of advanced age and pathologiescontact your kinesiologist».
Regenerative medicine
Physical exercise, not only in the context of rehabilitation but precisely as a lifestyle, is now being talked about in every medical congress. It has been studied, and validated, as a useful approach to alleviate a wide range of diseases, such as metabolic, neurodegenerative disorders, tumors and cardiovascular diseases. But even more excitement is arousing researchers about the ability of exercise to promote tissue regeneration. In fact, most adult human organs have a weak regenerative capacity, as confirmed by the often disabling outcomes of strokes, heart attacks and spinal injuries. A recent one has returned to talk about how exercise induces regenerative mechanisms studio appeared in a journal of the Nature group, reviewing the musculoskeletal system, cardiovascular system and nervous system (image below). In which it is clear that lo sport goes far beyond muscle and cardiovascular training andeffect on body composition.
After an accident that forces immobility or in the case of atrophy due to disease, the training exercise allows the regeneration of the muscle, its innervation and vascularization. The action of the training muscle contraction is also exerted on the osteoarticular system, therefore on theosso: «There is a relationship between muscle strength and bone mineral density» confirms Paoli. «The stimulus, made up of compressions and tractions, exerted by the muscle contraction on the bone shapes it. Physical activity is essential: it facilitates the accumulation of bone mass in youth and promotes its maintenance over the years. Analogous regenerative capacities are exercised on jointswhere the production of chondrocytes, the only cartilage cells, is promoted» and this is confirmed by numerous studies on physical activity in subjects with knee and hip osteoarthritis.
Heart. Unlike many other tissues, the non-heart is unable to regenerate and self-replenish heart muscle cells after a heart attack. However, studies have shown that myocardial cells respond to exercise by increasing in size and accelerating their proliferation. Sport is a nice protection against ischemic damage.
Central and peripheral nervous system. Exercise aids recovery after stroke or central nervous system damage by improving synaptic plasticity, promoting myelin regeneration and neuron survival, and facilitating brain angiogenesis. In patients with spinal cord injuries, exercise induces synaptic plasticity and restores sensory and motor function. The peripheral nervous system has a certain capacity for regeneration, which is enhanced by sport, proposed as a real therapy for those with peripheral neuropathy.
Other fabrics. The regenerative capacity of the liver is known, which is what allows us to donate a part of it without consequences for the donor’s health, but exercise promotes the production of hepatocytes, favoring recovery after transplantation. Numerous pieces of evidence also concern the skin, where it is even emerging that different physical activities favor the repair and regeneration of skin wounds of various kinds.
Finally, the production of new cells also affects the hematopoietic systemthat is, all those organs that deal with the production of red blood cells, white blood cells and platelets.
Naturally save money
We were born to move now takes on a much more radical meaning. Sport is a powerful, fun, economic strategy available to all for the protection of health. «We are a machine that must necessarily move not only to train the muscles, but to work in every sense» concludes the sports scientist. “Unfortunately, we have to deal with ancient evolutionary mechanisms that predispose to excessive and harmful energy accumulation in our modern environments, and curb any effort not directly related to survival such as escape or foraging.”
Photo by Alessio Soggetti (Pian delle Betulle, top) and Alora Griffiths (weightlifting) on Unsplash