I don't know why, they took up a sport, when young with a dream to participate in the olympics, they, their families and friends make huge personal sacrifices to make them international class competitors.
Every minute they spend in pain they are motivated by the Olympics, the early mornings, late nights training. The none existant social life, the absent partners that leave because they put their sport first.
Finaly after all those years of pain, sacrifice and self denial they achieve their dream. Nope no idea why they cry.