Winning a race requires a lot of hard work, discipline, and self-denial. Your training and preparation for the race requires you to give up a lot of the pleasures that you would normally like to enjoy. You have to set goals in order to push yourself toward the prize, because without them, self-discipline is just self-punishment. Everyone runs but only one person gets the prize.
Christians run toward a heavenly reward. It takes hard work and self-denial, but the prize is much greater than an earthly reward that will fade away. The heavenly reward for Christians is eternal. Sometimes we have to give up something that we think is good in order to do what God wants. If our goal is to please God, then our denial pales in comparison to the reward that awaits us. In this race, everyone that runs is offered the prize. All you have to do is ask and you will receive it. But you do have to enter the race... don't be a bystander!
1 Corinthians 9:25 (NLT) - "All athletes practice strict self-control. They do it to win a prize that will fade away, but we do it for an eternal prize."