Let me answer you. I was born in 1982. I am also 3 1 year old, 173CM, and weigh about 64KG. At present, I am working out. Is it similar to your situation? As for the fitness effect, it has little to do with age and physique. The key is a good fitness plan, which you can find in major fitness forums. I won't write it. One is a reasonable diet. As the saying goes, fitness means practicing three points and eating seven points. The most important thing is protein's supplement. First, get enough rest. Because muscles need a process of reorganization and recovery after training every day, you can't stay up late. It is best to stay up late every night 10. I'm practicing at home now, mainly one chest muscle, one abdominal muscle and one biceps (because these three pieces are the most intuitive haha). For chest muscles, you can use dumbbells at home, and push+birds+push-ups can also get good results. Dumbbells are also used for biceps. There are videos on the internet, and there are also video exercises on the internet. Remember, you can't grow muscles without protein. Eggs (up to two or three yolk a day, which is harmful to health), chickens, ducks, fish, shrimps and bean products are all good sources of protein. If you have no time to prepare food, you can buy whey protein powder, but you can't eat too much. As long as you persist, you will definitely reach a good figure. Come on!