Muscle strength comes from muscle growth and regular physical exercise. Adolescence is the fastest period of muscle growth and development, and about half of teenagers' weight gain is due to muscle growth. The synergistic effect of sex hormones and auxin contributed to the peak of growth and development.
1, growth period
The peak period for girls begins at 10~ 1 1 year. Although boys are two years late, the growth rate is obviously higher than that of girls. 1 1~ 16-year-old boys have doubled the total number of muscle fibers (that is, muscle cells), which is 30% more than that of girls, and the volume of muscle fibers has also exceeded.
2. The number of red blood cells in women is less than that in men.
Red blood cells carry oxygen, and the organic matter absorbed by the human body reacts with oxygen to generate energy in the body, just as we need to get more oxygen through breathing when we consume a lot of physical strength.
3. It is related to less androgen.
Estrogen allows women to store a certain amount of fat in some parts, such as the chest, buttocks and subcutaneous. Androgen, testosterone and male testosterone have a strong role in promoting the synthesis of protein, which makes male muscle fibers increase and thicken, bones thicken and hair grow, so boys' muscles are particularly strong due to the rapid increase of protein. ?
To sum up, arm thickness is not a measure of strength. Compared with women, men have more fat and muscles than women. Boys' muscle advantage is so obvious that their strength is naturally much greater than that of girls.