It has nothing to do with sports. You can take some of the simplest exercise methods. 1) Jump rope twice a day, with each jump above 100; 2) Insist on doing supine support twice a day, and do it for more than 20 times at a time; 3) Run 500 meters every day. Stick to it, and you will find yourself thin and strong, thin and healthy after half a year. These exercises are free.