Roger Federer remains an elite competitor at the highest echelons of world tennis.

But to stay on top of his game at 38 years old, he has to eat right.

For Federer, that means cheese.

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Roger Federer remains a fierce competitor at the highest echelons of world tennis.

He has 20 Grand Slam titles on his record, and he shows no real signs of slowing down.

Read more: One moment in Roger Federer's first clay match in 3 years shows how wrong he was to fear his return to the soft surface

As he turns 38 on Thursday, Federer continues to marvel on the courts. But to maintain his sporting dominance, he has to eat right. So what sort of food does the face of tennis eat?

Here's everything Federer likes to have for breakfast, lunch, and dinner.