They are tears of joy. Athletes work SO hard and they love their sport so much, so when they win it just shows them that their hard work has finally payed off. Also all of the pressure that is put on them during the competition is so intense that when they win it is like a weight lifted off your shoulders.
They cry after the win because they feel like some pressure was released from them and because they are simply happy that they achieved something in their career.
They get the successful feeling..they feel like a champion..and they cry for it because they are so happy getting their dream come true
They are happy that they worked hard and finally accomplished something.
haven't you heard of tears of joy?
jw