Exercising abdominal muscles requires persistent exercise. It is impossible for muscles in all parts of the body to exercise every day, which will affect muscle growth. In addition to abdominal muscles, if you want to exercise beautiful abdominal muscles, you must persist. You can watch more videos on the internet and choose a few that suit you.
Like me, I simply tried for half an hour, and there was no numbness or burning sensation in my abdomen. It's too difficult for you to make a few, and it doesn't work. In my experience, just choose a few moves, preferably 20-30 moves, you can't stick to it.
It is best to include comprehensive movements, including end-abdomen, twisting the body left and right when sitting up, so that the abdominal muscles are smooth and beautiful. I can't say anything professional, but I still have to see more and do more to know what suits me.
Also, abdominal fat is mostly thick, even if there are abdominal muscles, it will be covered by fat. It is best to do it with itchy sports, such as running, cycling and swimming, about 3 times a week! Every half an hour ago, itchy exercise can consume whole body fat, which refers to body fat.
In addition, the parts of one-handed pull-ups and two-handed pull-ups that need to exert force are roughly the same, basically the same. If the muscle inside the big arm is called biceps brachii, then the pull-ups with both hands are adducted by biceps brachii and deltoid.
If one-handed pull-ups, it is difficult to keep the body facing straight ahead, so the main force of one-handed pull-ups should be biceps brachii and deltoid muscle.
Pull-ups are a comprehensive action, involving many muscles or muscle groups, including forearm muscles, biceps, deltoid muscles, back muscles (including latissimus dorsi you want) and pectoralis major muscles. If you use pull-ups to exercise latissimus dorsi, such as the horizontal bar, you need to put your head forward, put your arms behind your head, and exert strength on your back, that is, pull your body up with the strength of your shoulder blades.
That's all I'll tell you!
Wish you success and happiness!