Rectus abdominis is a long, flat muscle, which begins in the pelvis and ends in the ribs. Its contraction range is very short, and its main function is to bring the pelvis and ribs closer together, bend the spine forward and stabilize the trunk. A slender tendon separates it from it.
The external oblique muscle of abdomen starts from rectus abdominis and ends in latissimus dorsi, covering the front of abdomen. Its muscle fibers move obliquely into a V-shape. Below is the internal oblique muscle.
2 Action choice
Sit-ups and sit-ups have always been considered as methods to develop abdominal muscles. Actually, it's not. They just train gluteal flexors, while abdominal muscles just keep the trunk stable.
Effective action
Leg rest sit-ups: Lie on the ground, put your feet on the bench, contract your abdominal muscles and roll your upper body up to your waist, keeping your lower back close to the mat during the action. Mainly concentrated in the upper abdomen.
Reverse leg-rest sit-ups: the load comes from the weight of the legs.
Starting posture: lying face up on the mat with arms at your sides. Bend your knees and lift your thighs so that they are perpendicular to the ground.
Action process: Inhale and contract the abdominal muscles to move the buttocks to the chest.
Note: Keep your knees bent. Squeeze the muscles at the apex to reduce control. A master can roll up his hips and move his head and shoulders to his waist.
Hang your legs and lift your knees: Straightening your legs can increase strength. Your feet shouldn't touch the ground during exercise.
Starting posture: the arms and lower limbs are fully extended, the spine is slightly bent, and the breath is held until the legs are slightly backward.
Action process: lift your legs up, straighten your legs but don't lock them. Bend the hip joint as much as possible to reach the peak of contraction.
Beginners can bend their legs or lift their knees.
Oblique muscle
Overdevelopment of oblique muscles will make your waist thicker. In strength training, for example; Squats and other events will develop oblique muscles. So I suggest you don't do weight-bearing training for oblique muscles. Just add a twist when doing sit-ups
According to my personal experience, the training of abdominal muscles is quick and simple, and there will be obvious changes in a week.
As for being strong, do more exercise. Simple bodybuilding training is not healthy, or aerobic exercise is the main thing.
To be strong, you need muscles. I think the best indoor exercise is push-ups, which can exercise pectoralis major and arm muscles, and it is best to do push-ups in several groups (it is estimated that it is almost enough to start doing 2-3 groups of physical strength). The number of push-ups in a group is at most 70% of the best you can do. Only in this way can it be effective, so we must stick to it. After practicing pectoralis major, even if I lose weight, I look strong and masculine. Secondly, it is also very important to practice abdominal muscles, and the methods are the same, but it is necessary to persist in practicing abdominal muscles, and it is best to persist every day to be effective. I just didn't stick to it, so I didn't practice abdominal muscles, only chest muscles. I feel very sorry. I think it's almost enough to practice these two items indoors. Doing pull-ups outdoors and practicing on parallel bars are also very effective for exercising arm muscles and strength. Personally, I think it is a good choice to exercise the upper body, waist and abdomen, and also exercise the strength of lower limbs (running, mountaineering and cycling).
For food, I don't think it is necessary, because we are not professionals, just eat enough. If you really want to pay attention to your diet, you should eat more protein. Besides lean meat, eating steamed bread in the morning is also very effective.