Quick straight-leg sit-ups. It will only exercise the buttock muscles, and the abdomen will be exercised very little, and the effect will not be very significant. Because most of the time, you're borrowing momentum, especially if your arms are straight behind your head or you're using your arms to push your head up. The correct posture should be to bend your legs or place them on a stool, place your hands gently behind your back, and contract your abdominal muscles to slowly get up.
How to build strong abdominal muscles
The abdomen is at the center of the body and is a particularly eye-catching part. From the perspective of human body building, a truly toned abdomen should consist of a thin and powerful waist and well-defined abdominal muscles. Therefore, please don’t neglect abdominal toning exercises.
1. Bending sideways and upright. Separate your legs, raise your arms to the left and right, bend your upper body forward, use your left hand to reach your right foot, raise your right arm naturally, do not bend both legs and arms, inhale, then restore, and exhale. Change direction and repeat again, 8 times in a row.
2. Leg bending exercise: Supine position. Place your arms flat on the ground left and right, straighten your legs and lift your knees at the same time. Inhale to bring your thighs close to your abdomen, then exhale and slowly return to the position. Repeat 8 times.
3. Leg raises and abdominal contractions mainly exercise the lower abdominal muscles. Lie on your back with your upper body straight, lift your legs as high as possible, and then slowly lower them. After completing this exercise, bend your knees and continue doing the same movement. Repeat 8 times.
4. Sitting and flexing: The supine position mainly exercises the upper and lower abdominal muscles. Straighten your legs, lean your upper body back to maintain body balance, and then bend your knees and tuck your abdomen in to make the abdominal muscles extremely flexed. During the exercise, your feet should never touch the ground or bed.
5. "Cycling" exercise: Supine position. Take turns to flex and extend your legs, imitating the motion of riding a bicycle. The movements should be fast and flexible, and the range of flexion and extension should be as wide as possible. It lasts 20~30 seconds.
6. Twist: Hold the handle with one hand or pull a heavy object of a certain weight, and perform twisting and turning exercises in various postures to exercise the oblique and waist muscles.
Everyone can choose the above exercises according to their own situation, and according to their physical condition, the amount of exercise each time should be from small to large, gradually increasing, and done twice a day..