The standard of one-minute sit-ups is 30 for girls and 40 for boys, with an average of 35 minutes.
The correct way to do sit-ups is as follows:
Lie on your back on the mat with your knees bent about 90 degrees and your feet flat on the ground. Don't fix your feet on the flat ground, or the flexors of thighs and buttocks will join the work, thus reducing the workload of abdominal muscles.
Furthermore, straight leg sit-ups will increase the burden on the back and easily cause damage to the back. Determine the position of your hands according to the strength of your abdominal muscles, because the closer your hands are to your head, the more difficult it will be to do sit-ups. Novices can put their hands on their sides, and when they get used to it or improve their physical fitness, they can cross their hands on their chests.
Finally, try to cross your hands behind your head, but put your hands on the shoulders on the other side of your body.
Note: Never put your fingers crossed behind your head, so as not to strain the neck muscles when exerting force, and this will also reduce the workload of abdominal muscles.
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.
Extended data:
Many women under the age of 30 practice for the purpose of preventing gynecological diseases. At this time, the frequency should be controlled at 60 ~ 70 beats per minute, which decreases with age. It is enough for people over 50 to do 25 per minute. For people who have a certain fitness foundation, they want to strengthen their abdominal strength through practice and ensure that they do it about 60 times a minute.
Sit-ups are an important part of physical exercise, and their main function is to strengthen abdominal muscles. If done correctly, sit-ups can not only improve the elasticity of abdominal muscles, but also protect the back and improve the posture. On the other hand, if not done well, sit-ups are not only a waste of time, but even harmful.