First of all, there is something wrong with the bike. There are not only the quality of the bicycle itself (the riding angle of some inferior bicycles is not ergonomic), but also the choice and adjustment of the bicycle itself, such as the size of the frame, the height of the seat, the elevation angle of the seat, the height of the handlebar and so on.
Second, riding is unscientific. There is a lot of knowledge in it, such as pedaling with the forefoot, not using internal and external characters, using the speed change system reasonably and adjusting the rest regularly.
Third, there are patients who are not suitable for cycling, such as waist injury, sciatic nerve, leg injury and foot injury.