Researchers identified 15 published studies including 899 subjects that compared pain perception between athletes and non-athletes.

Athletes had higher pain tolerance than non-athletes, but no consistent difference in pain threshold (the minimum intensity at which a stimulus is perceived as painful) was found.

Response to pain was somewhat sport-dependent. Does regular exercise help increase pain tolerance or are people who can tolerate pain more likely to be regular exercisers?

Further studies will be needed to clarify the issue.

In the meantime check out what happens to an athletes body as he tackles 89km of tarmac