We all know that good old Nike slogan: Just do it. You might also know that, for all its simplicity, this piece of advice is often hard to follow. Why? Negative thinking stops us from reaching top performance.

It’s funny how our thoughts seem to impact us precisely the way we don’t want them to. If, while playing golf, you tell yourself not to hit the water, you’re likely to hit it anyway. Why? Your thoughts were so focused on the water that your body began aiming for it, too. Avoid outcomes like this by keeping it simple and focusing on what you want, not all the things you’re afraid might happen.

Of course, the power of thought alone can’t carry us toward success. It’s the combination of physical and mental training that allows us to perform to our full potential. One study of three groups of basketball players demonstrated just this.

The first group took free throws for one hour, the second sat and visualized their free throws for an hour, and the third did both for 30 minutes each. When it came to the free throws afterward, the third group outperformed the others by far.

While most of us know more or less how to train our bodies, few really know what to do when it comes to training our brains. Like our bodies, our minds have their own strengths and weaknesses. Pinpointing these will give us both confidence in our abilities and a clear idea of where we need improvement.

Get started on your brain training journey by learning simply for the sake of improving yourself one step at a time without stressing too much about the final outcome. If you think like this, you’ll have an open mind ready to take in anything that can make you a stronger, better person.