[Sakibomb25]

Not only was she wearing one, but two Gators caps in the process. 

All pro swimmers wear two caps. The first one is used to cover their hair, as latex clings to the head better. The second silicone one doesn't crinkle as much as latex, so it smooths any lingering bumpiness on the head. Without the second cap, there is more drag in the water because the first one could wrinkle.

If she were still swimming at Stanford, she'd be wearing two Stanford caps.

[Sakibomb25]

Not only was she wearing one, but two Gators caps in the process. 

All pro swimmers wear two caps. The first one is used to cover their hair, as latex clings to the head better. The second silicone one doesn't crinkle as much as latex, so it smooths any lingering bumpiness on the head. Without the second cap, there is more drag in the water because the first one could wrinkle.

If she were still swimming at Stanford, she'd be wearing two Stanford caps.