When Carson Palmer, a professional American football player, hurt his arm a few years ago, he took a week off to stop throwing the football. But in his head, Palmer practiced every day. The following weekend, Palmer had the best game of his life.
For more than a century, scientists have been trying to understand how this mental training works. In the 1930s, researchers proved by experiment that when you're imagining an action, your brain sends signals to your muscles which are too weak to tighten the muscles but might help train the body to perform. In other words, mental practice might create a plan in your head, like a how-to guide for a special skill.
Sports researchers have done hundreds of studies comparing imagined and physical practice for actions. In short, the studies show that mental training works. A 2012 study compared 32 nonprofessional golfers with another 32 who only imagined their action. Under the same training program, both groups improved their skills.
Imagination has advantages over the real thing: You can do it anywhere and any time. It is safe—a main advantage for people such as gymnasts and doctors. And you can practice for longer periods of time because you're not controlled by physical tiredness. That's not to say it's easy. "we've had Olympic-level sportsmen sitting in our laboratory, imagining for two hours," says Tadhg Macintyre, a sports researcher in Ireland. "When we're done, they're completely tired."
It doesn't work for everyone, though. "If you're a beginner, the influence can be harmful," warns Macintyre. If you're trying to imagine a free throw, and you don't even know the proper movement, then you're probably going to mentally practice the wrong skill, and your skill is going to be impaired."
