1. Increase the risk of injury: Without proper stretching, the flexibility of muscles and joints may be reduced, which may easily lead to sports injuries such as sprains and strains.

2. Affect muscle recovery: Stretching can help muscles relax, promote blood circulation and help muscle recovery. If you don't stretch, the muscle recovery time may be prolonged, which will affect the exercise effect.

3. Increase muscle tension: After maintaining the same posture for a long time or carrying out high-intensity exercise, the muscles will become tense. Stretching can help relieve muscle tension and improve sports performance.

4. Aggravate muscle stiffness: If you don't stretch for a long time, your muscles will become stiff and your joint range of motion will be limited, which will affect your daily life and sports performance.

5. Affect the flexibility of the body: Stretching can increase the range of joint activity and improve the flexibility of the body. Without stretching for a long time, the range of joint motion may gradually decrease, affecting daily activities and sports performance.

6. Delaying fatigue elimination: Stretching helps to relieve muscle fatigue and promote blood circulation. If you don't stretch, fatigue may not be completely eliminated, which will affect the exercise effect.

In order to protect health and improve sports performance, it is suggested that proper stretching exercise should be carried out after fitness.