First of all, I recommend push-ups. There are many ways to do push-ups, such as lifting your hands, lifting your legs and so on, but for your waist, the most popular and common one suits you best. The most common push-ups do not need strong waist and abdomen strength, and there are many exercise parts for push-ups, and both the muscles on the arm and the abdominal muscles can be exercised to a certain extent. Of course, after all, you have a little problem with your waist, so you don't need to do too many push-ups. You can do 20 push-ups at a time and do three groups. Each group can rest for about 30 seconds to a minute. You don't need to do many push-ups. The key is to persist. Long-term persistence will naturally strengthen upper limb strength and abdominal muscles.
Secondly, what I want to say is pull-ups. In fact, this is similar to push-ups, except that one hand holds up half of the body and the other hand holds up the whole body, so in terms of exercise intensity, the effect of pull-ups will be better. After all, the whole body is about 100 kg. Of course, there are also some things to pay attention to in pull-ups. When you do it, hold the palm of the sling outward. When you go up, your neck should exceed the sling, your arms should be fully relaxed, and your head should not go up and down near the sling. This kind of exercise will have a poor effect and make your neck ache. Only when your hands are fully relaxed can you achieve the best effect of exercise. Of course, the amount you do depends on your physical condition. Don't force yourself to get hurt.
The last exercise I want to recommend is the exercise that you can do while lying in bed, that is, lying on your back, then lifting your feet and imitating walking for a few minutes. In the long run, you can strengthen your abdominal muscles and strengthen your abdominal muscles, but it is not helpful to exercise your arm strength, so I suggest standing upside down for a few minutes before doing the above exercise, and the effect will be better.