Here is why football players apply black stripes underneath their eyes in a game.

It's a phenomenon called "eye black."

Natural skin absorbs some light, but reflects the rest. This reflection can cause glare and impair vision. Black stripes are supposed to prevent this by absorbing all of the light. This makes it easier to track the ball in midair.

Eye black is also common in baseball and lacrosse. In fact, one of the first people to wear it was Babe Ruth.

Babe Ruth began the trend back in the '30s but the first scientific analysis didn't turn up until 2003. Since then, a few small studies have tackled the topic.

The MythBusters even did their own test.

The verdict? While eye black does not appear to reduce glare, it does improve the ability to differentiate between light and dark.

The results have raised another question. Does this ability actually enhance athletic performance? That's a mystery still waiting to be solved.

In the meantime, athletes can don their black stripes proudly.