The standard weight of 1.7 meters is about 120 kg, but considering that you are still a developing teenager, if you think about losing weight, entering adolescence will affect endocrine, and what diseases will you get? If you exercise from a healthy point of view, you can continue to jump rope. At night, 4 pm to 6 pm is the best exercise time for the human body, and it is easier to consume excess fat. However, dumbbells used to strengthen the body and exercise muscles have enhanced the vital capacity of pectoralis major. What, do you want to lose weight? It doesn't seem appropriate.