Flexibility training improves stretch

The answer is actually very clear. The core function of flexibility training is to improve the stretchability of skeletal muscles, tendons, ligaments, joint capsules and the connective tissues that wrap these tissues. Incidentally, it can also increase the flexibility of joints within their normal range of motion. In the five or six years I have been running cross-country, I have seen too many newbies who cannot even stretch the quadriceps muscles on the front of their thighs at first. They have to stand on tiptoe when squatting to pick up something. Their knees hurt after running for three to five kilometers. In fact, the muscles have stiffened from sitting for a long time and have become "hard rubber bands" with poor stretchability. They cannot stretch or close when exerting force, which is of course prone to problems. A full marathoner I once coached was even more exaggerated. At first, the iliotibial band was so tight that it hurt even when I lay on my side and raised my leg. The outside of my knee kept getting stuck when running. I thought it was a bone problem. Later, I relaxed with a foam roller and static stretched three times a week. After two months of training, my hip abduction range of motion increased by 15 degrees, and the problem of running stuck was basically eliminated.

But when it comes to this, I have to mention that there are actually different views in the sports circle on "which kind of stretch should be given priority to improve." The old-school training system places more emphasis on passive stretch, which is the range of motion achieved by someone else pressing it for you or pulling it out by your own weight. For example, the passive shoulder and hip opening in traditional yoga pursues the maximum range that soft tissue can stretch under static conditions. However, in recent years, more and more physical coaches prefer to practice active stretching, which is the ability to stretch your muscles and maintain stability when you actively exert force. After all, our daily walking, running, jumping, and moving things are all scenes of active stretching. It can be stretched only passively. When actively exerting force, the soft tissue is still stiff, and it is still difficult to use when actually using it. There was a girl in my previous team who had practiced Hatha Yoga for three years. She could reach her ankles by passively lowering her waist. Last time she went hiking with us on a wild trail and she still fell when going down a steep slope. This was because her ankles were not stretched enough by active dorsiflexion when going down the mountain. When she stepped on the uneven road, her ankles had no time to pull away to relieve the force, and they buckled instantly.

In fact, there is no need to worry about which view is more correct, it just depends on your own needs. If you want to practice gymnastics, rhythmic gymnastics and other sports that require extreme ranges, the passive stretch must be fully stretched. If it is ordinary fitness and daily exercise, it is more practical to give priority to stretching in the active state. For example, do more dynamic lunges and the greatest stretch, which is much more useful than sitting and pressing your legs for a long time.