Use a slower speed, just like slow-motion playback. When the abdominal muscles pull you up, you have to exhale, so as to ensure that all the muscles deeper in the abdomen participate in the work at the same time.
After the body is off the ground 10 to 20 cm, tighten the abdominal muscles, pause for a while, and then slowly lower the body back to its original position. When your back touches the ground, you can start the next cycle. In the process of sit-ups, the abdominal muscles actually only participate in the work at the initial stage, and then the hip flexors will replace the task.
National students' physical health standards:
1. The National Standards for Students' Physical Health (hereinafter referred to as the Standards) is the basic guiding document of national school education, the basic standard of education quality, and an important basis for evaluating students' comprehensive quality, evaluating school work and measuring the development of education in various places.
It is the concrete implementation of "National Physical Training Standards" in schools, and is suitable for students in full-time ordinary primary schools, junior high schools, ordinary high schools, secondary vocational schools and ordinary colleges and universities.
2. The revision of this standard adheres to the principle of health first, and implements the Outline of the National Medium-and Long-term Education Reform and Development Plan (20 10-2020), the Notice of the General Office of the State Council on Forwarding Some Opinions of the Ministry of Education and Other Departments on Further Strengthening School Physical Education (Guo Ban Fa [2012] No.53) and the Ministry of Education on Printing and Distributing Students' Physical Health Monitoring and Evaluation.
Refer to the above contents: Baidu Encyclopedia-National Student Physical Health Standard (revised on 20 14)