Muscle training is also an important exercise, just like aerobic exercise. When we think of muscle training, we tend to think of high-intensity exercises like weight training. However, muscle training does not only mean doing advanced muscle training at a sports gym. It is said that low-intensity muscle training is also useful. This muscle training is sufficient three days a week. In a sense, it may be an exercise that makes you feel better if you think that you can take a break four days out of seven. The increase in skeletal muscle through muscle training is effective in preventing and improving lifestyle-related diseases. Increasing muscle mass increases metabolism and improves fat burning efficiency. It prevents obesity and lifestyle-related diseases.
In recent years, it has been discovered that these muscles secrete hormones. Organs that secrete hormones were known to be the pituitary gland, pancreas, thyroid gland, and adrenal glands in the brain. It was only in the 2000s that it was discovered that muscles also have a similar function to organs that secrete hormones. Hormones secreted by muscles are collectively called "myokines." More than 30 types have been identified so far. Myokines are secreted from muscles when they are moved. It is now said that "muscles are the largest endocrine organ in the human body." Furthermore, it was previously said that commands were sent unilaterally from the brain to the muscles to move them. Now, it has changed and it is said that the muscles also send commands to the brain. Furthermore, the value of muscles is increasing. Some of the hormones secreted by muscles are expected to have the effect of preventing dementia and cancer.
Until now, it has been said empirically that exercise is good for preventing dementia. This is now being proven. After being secreted from muscles, the myokine irisin travels through the bloodstream to reach 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 the substance BDNF is secreted, nerve cells that are useful for information transmission are created. As a result, it has been found that when this substance is secreted in large amounts, brain function is enhanced. This increased brain function seems to prevent dementia.