Running is an aerobic exercise.
Answer:
Answer pta h par dunga nhi smjha!!
Well because this is health I am assuming they are referring to the health side of the sport. The concussion rate in the sport is super high, higher than most sports even with the padding and helmet protection. It is also a high contact sport so injuries are bound to happen.
Alternating between running and walking can help lessen the damaging effects that running has on the body.