How about doing sit ups all the time in a row?

The main effect of sit-ups is to strengthen the abdominal muscles. When done correctly, sit-ups can improve the elasticity of your abdominal muscles, while also protecting your back and improving your posture. On the other hand, if done incorrectly, sit-ups are not only a waste of time, but even harmful.

According to Stamford (1997), the correct practice of sit-ups is as follows: Lie on your back on the mat with your knees flexed at about 90 degrees and your feet flat on the ground. Do not immobilize your feet on flat ground (e.g. by a partner pressing your ankles with your hands), otherwise the flexors of the thighs and hips will join the work, reducing the workload of the abdominal muscles.

In addition, straight-legged sit-ups will increase the burden on the back and easily cause damage to the back. Decide where to place your hands based on 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. Beginners can rest their hands on their sides, and when they have adapted or improved, they can cross their hands over their chest.

Finally, try to cross your hands behind your head, but each hand should rest on the shoulder on the other side of your body. Do not cross the fingers of your hands behind your head to avoid straining the neck muscles when you exert force, and this will also reduce the workload of the abdominal muscles.

It is advisable to proceed at a slower tempo, as is the case with slow-motion playback. Exhale as your abs pull your body up to ensure that all the muscles in the deeper layers of your abdomen are working at the same time.

After raising your body 10 to 20 cm off the ground, tighten your abdominal muscles and pause for a moment, then slowly lower your body back into position. When your back hits the ground, you can start the next cycle. During sit-ups, the abdominal muscles are only involved in the initial phase, after which the hip flexors perform the task.

In the same way, turning the body in the final stages of sit-ups (right elbow touching left knee, left elbow touching right knee, etc.) not only does not do much to strengthen the abdominal muscles, but can even cause trauma to the lower back due to the pressure of the rotation.

Beginners should avoid doing too many sit-ups at once, try to do 5 reps at first, then add one more time to each exercise until you reach about 15 reps, and then try to do one more set until you reach 3 sets.

If you pull the ligament and keep doing it, you will have pain on both sides of the kidney, so you can say kidney.

It's better not to do too much at once, sometimes the muscles can't stand it.

Oh to tell you the truth, there's no trick, just take it step by step.

And if you're not going to take exams when you're in school, don't control your time, the number of times is the most important.

If you want to cope with the exam, you can only practice more.

Adjust your breathing and choose the distance between the focus point and your feet.