During Disc 3 as Vivi in Alexandria you can participate in a mini-game with Hippaul. He's with his mom on the second screen in town. His mother has decided that he's too fat and needs to excercise so she asks Vivi if he will race Hippaul. You race by alternating pushing the Circle and Square buttons. As you increase your speed Vivi's strides will increase in length. But if you hit Circle or Square twice in a row he will slow down.

Hippaul does increase in level as you progress through the game. After each ten levels Hippaul's mother will give Vivi a reward:

After Vivi receives the Athlete Queen award at level 80 he won't receive any more rewards but you can continue to play up to level 100. Also, if you've gotten the Athlete Queen when you read the letter in Treno about a sprinter it will be Vivi instead of Hippaul.

Note that this is the only time during the game you can pursue this quest. Also, if you agree to see Ruby's play you won't be able to play the mini game any more.