Dear ~ I tell you, I am thin, but I went without any physical exercise. What matters is determination! However, physical training, if any, will be slightly adapted. The Sichuan-Tibet line cannot ride 40KM every day. The trick is: you must try to break your limits. Try to ride above 100KM, which is more useful than riding 40 every day, and slowly increase it until you can ride 200KM. The most uncomfortable thing about going to Sichuan-Tibet line is egg pain. My inner thigh is really rotten. Later, I slowly run in! I suggest you buy cycling underwear and cushions, then go for a long ride and get used to it! I went in the summer vacation in July, 20 1 1. Well done! Come on! Then give me the gold coin, I need it urgently!