Muscles are increasingly being evaluated as a measure to promote health. Some hormones (myokines) secreted by muscles have been shown to be effective in preventing dementia and cancer. Until now, it has been said empirically that exercise is good for preventing dementia or delaying its onset. This is now being proven. It has become clear that myokines also have the effect of suppressing diseases other than dementia. After being secreted from muscles, a myokine called irisin travels through the bloodstream to the brain. When irisin reaches the brain, a substance called BDNF is secreted in large amounts in the brain. BDNF stands for Brain Derived Neurotrophic Factor. When a large amount of this substance called BDNF is secreted, nerve cells that are useful for information transmission are created. As a result, it has been found that when a large amount of this substance is secreted, brain function is enhanced.
On the other hand, it has also been found that when muscles atrophy, brain function is reduced. Atrophied muscles are less likely to secrete myokine hormones that have a positive effect on the brain. Furthermore, atrophied muscles begin to secrete hormones that act in the direction of declining cognitive function. Atrophied muscles begin to secrete a hormone (hemopexin) that acts in the direction of declining cognitive function. This hemopexin acts on the hippocampus and even promotes the onset of dementia.
So, what can we do to increase the muscles that promote health? It is by exercising. When we exercise and use our muscles, the muscle tissue is damaged and blood comes out. Muscles have the property of increasing by being “damaged”. The mechanism by which muscles increase by being “damaged” is called “supercompensation”. Exercising to the point of feeling muscle pain is effective for this supercompensation to a certain extent. The injury and blood coming out act as a switch, causing muscle hypertrophy. In muscles damaged by bleeding, stem cells, which are the source of muscle growth, become activated and proliferate. When stem cells become activated and proliferate, and attach to muscle fibers, the muscle fibers become thicker and new thick muscle fibers are created. Exercises that increase muscle fiber to a certain extent is believed to be useful even at low intensity. Increasing muscle mass increases metabolism and improves fat burning efficiency. Furthermore, an increase in myokines helps prevent lifestyle-related diseases and dementia.
