Cycling is a dangerous sport, and it is very easy to get injured if you are not careful. For example, in track cycling, athletes have to race at a speed of seventy kilometers per hour on a sloping track. Under such high-speed conditions, even slight contact between athletes can lead to serious consequences. In particular, if several athletes fall together, the impact on them could be as severe as a car collision accident. Therefore, we should respect those brave "knight-riders" on the field even more!