Here comes the next frontier in training.

It’s the brain. Evidence suggests that an athlete’s gray matter is fundamentally different from another person’s. And if this is the case, then the brain — more than ever — controls all three aspects of performance: physical, mental and emotional.

In the April issue of Discover magazine, author Carl Zimmer cites a number of studies on athletic performance and the brain. In one, scientists at the University of Regensburg in Germany scanned subjects as they were learning to juggle. Not only did certain areas of the brain grow, but they continued to change for months.

In another, a researcher at Sapienza University in Rome scanned the brains of many people, some of them professional basketball players, as they watched movies of other people shooting free throws. The pros, it turns out, mentally re-enacted free throws.

Then comes this sentence: “These studies are beginning to answer the question of what makes some people great athletes: They are just able to rewire their brains according to certain rules.”

Knowing what these rules are, and then knowing how to proceed, is the next frontier.

But for now, no mater what the event — March Madness, Stanley Cup playoffs, NBA playoffs, or Opening Day of baseball season — there will be a lot of brains at work.