If you have perseverance, you don't need to change for the time being. Just add a few more times. Besides, you must think the heavier the exercise, the better, right? You can get 100 when you are physically strong. But can you get 100 at any time? For example, I just got up in the morning. Although I am a second-class disabled person (due to a car accident), I still insist on doing exercise before taking a bath every day. And how many dumbbells should I buy to suit myself? Too heavy is not recommended. It is enough to practice the same number of times. It is recommended to buy two ordinary weights. (ten Jin is recommended. How many days are you sick in a year? If you use ten pounds, it won't hinder your exercise. In addition, if you want muscles, you have to practice more, because the formation of muscles is endurance. Just like I exercise every day now, although I am a second-class disabled person. (If you say strength now, you may not be like me. It's hard to say if I compare explosive power with you. But compared with endurance, you lose. )