Today at Mass the priest used this saying in his homily. He said how in sports, enduring temporary pain often leads to victory. Basking in victory, the pain is forgotten.
It's like that in the spiritual life too. It's hard to practice virtue, to deny ourselves things, to put others' needs before our own. Jesus said it too in the Gospel, "How rough the road that leads to life!" But to keep the goal in mind makes it all worthwhile.