For example, the main way to exercise the thigh is squat, so you need to pay great attention to the details. Generally beginners do this action, and the whole body's center of gravity is on the position of the knee. On the contrary, there is no load on the thigh, which not only can't exercise the muscles on the thigh, but also will soon damage the knee. This is the first difficulty I encountered in sports, because it is more difficult for people who have made mistakes to correct them, so I must continue to do it under the condition that my thighs and abdominal muscles are exerted and my knees are not.
Here's how to do squats correctly: for people who often make mistakes, you should tilt your ass back first. At this time, your thighs will stay tight, and then squat down, and your thighs will not relax. This is naturally the strength of the thigh. In fact, it is divided into two actions. Many novices squat down directly with their hips on their backs. It is very likely that two actions cannot be done at the same time.
Another example is push-ups. As a very effective action to exercise the pectoral muscles, we should pay attention to its force characteristics: when your arms are relatively open, more of your external pectoral muscles are exerting force, deltoid muscles assist in exerting force, and your internal pectoral muscles hardly participate; When your arm is shoulder-width or even narrower than your shoulder, it is mainly the inside of pectoralis major that exerts force. Although the latter is more difficult to do, we still have to combine the two movements and do only one movement, which will easily lead to strong external muscles and relatively weak internal muscles.
There are many details to pay attention to when exercising, so when you want to start a new movement, ask the coach or other people who have exercised with this movement, so that you won't make some small and key mistakes again.