Whether it’s interviewing for a job, sitting for a big exam or playing for the tournament trophy, worries about screwing up can prevent us from performing at our best. But what if there was a simple technique you could adopt that would help ensure that you sail, rather than fail, when the pressure is on? And, what if this technique requires neither a lot of time, resources, nor effort to accomplish?

Some striking new psychology research shows that spending just 10 minutes writing about your thoughts and feelings before a high-stress event can boost performance when it matters most. You might think that writing about your worries and self-doubt would make the negativity more salient rather than less, but that’s not what scientists have found. Rather, putting negative thoughts down on paper downloads them from mind, making them less likely to pop up and derail you in an important moment, such as the final of a tournament.  
For many years scientists have known that expressive writing, in which people repeatedly write about a traumatic or emotional experience over several weeks or months, can effectively decrease rumination about events that have happened in the past. Scientists also recently discovered that people facing an upcoming pressure-filled situation can benefit from getting their worries on paper in the few hours immediately before they perform.  
When we find ourselves in high-stakes situations, whether it’s a final, another match against a rival, or a contest that will have meaning not just for you, but your tennis team, we worry about the situation and its consequences. These worries are problematic because they can deplete a part of the brain’s processing power known as working memory. Although working memory isn’t necessary to guide such habitual or automatic actions as a forehand or serve we’ve practiced to perfection, it does come into play when planning game strategy or trying to predict what shot an opponent will attempt next. When worries creep up, we are robbed of the brain power necessary to be smart on the court. Writing down these worries ahead of time helps get that power back.  
But, how can such a simple writing exercise have such a big impact? And, why doesn’t chatting with a friend, teammate, or coach have the same effect? The answer has to do with the content of the writing itself. Writing reduces the tendency to ruminate because it not only provides us with an opportunity to express our concerns, but to re-read them and gain insight into the source of our stress. Perhaps you realize that the situation isn’t as pressure-filled as you initially thought or that you have the tools—you’ve practiced and done your homework on your opponent—necessary to excel. When you gain this type of insight, your tendency to worry during the actual pressure-filled situation decreases.  
So, next time you’re stressed about going onto the court, do all the things you normally would do to get ready for the big day. But, also do your worry writing a few hours ahead of time. It just might be what puts you over the top and helps you outsmart your opponent on the court.

Sian Beilock, Ph.D., is a psychology professor at The University of Chicago and the author of Choke: What the Secrets of the Brain Reveal About Getting It Right When You Have To.