The finding: When people imagine practicing a skill or sport during “lucid dreaming,” the state in which a sleeping person recognizes he’s in a dream and takes control of it, their performance in that activity improves in real life.

The research: In field experiments that required people to toss coins into a coffee cup from a distance of two meters, participants who dreamed they practiced the task significantly outperformed those who didn’t—though not quite as well as the participants who actually practiced the coin toss while awake.

The challenge: Can people really use dreams as a training regimen? Dr. Erlacher, defend your research.

Dream Practice Versus Real Practice Erlacher tested 40 subjects twice on their ability to toss coins into a cup from a distance of two meters. Between tests, subjects were asked to practice the toss, dream they practiced it, or do nothing. Here’s how they fared:

Erlacher: This is definitely not mainstream research. There are some people who say that dreams are nonsense and aren’t worth investigating. Critics say that you can’t really be sure people are dreaming, and some of the field studies we’ve done—including the coin toss study—haven’t yet been replicated in a sleep lab. But there is substantive research here. It has been well established that athletes who mentally rehearse an activity can improve their performance, and it makes sense that dreams can achieve the same effect.

In one experiment we asked participants to dream about doing deep knee bends. Even though their bodies weren’t moving, their heart and respiration rates increased slightly as if they were exercising. So your brain is responding to the dream movements in similar ways, and that allows you to use dreams as a simulation. You can learn from that.

HBR: Some of this research sounds absurd, like the man who claimed he taught himself in his dreams to ride a unicycle.

That was a German researcher who didn’t do experiments in a sleep lab—he wrote about what he believed should be possible and demonstrated some of these activities himself. Much of his work involved balance-related tasks. He started out dreaming about skateboarding, and he became really good at skateboarding during wakefulness. He claimed that by practicing in his dreams, he’d learned to snowboard so well that he could do it without bindings, which is almost impossible. I’ve spoken with people who went snowboarding with him, and they watched him do it. So there has been some validation.

How do you find people who have lucid dreams for your experiments?

That’s the most complicated part. In Germany, where we do our research, about half the population is familiar with lucid dreaming and reports having experienced it. But only 1% of people have lucid dreams every night. You want to find that 1% so you can avoid unproductive nights in a sleep lab. To locate these people, we put ads in newspapers. We use a recruiting website. We rely on word of mouth. But it’s still very difficult.

Can people learn to lucid dream?

Yes. There are several techniques. One involves waking a sleeping person up after six hours, keeping her awake for an hour, having her rehearse the dream, and then sending her back to sleep for three hours. In one study 50% of people who tried that had a lucid dream during the second sleep period. I used a different method, called the reflection technique, to learn to do it. It involves stopping what you’re doing 10 times a day and asking: “Am I dreaming, or am I awake?” That helps improve your critical facility so you become better at recognizing a dream in progress. After two months I had my first lucid dream: I was in my parents’ kitchen, and I decided to fly out the window and around the neighborhood. Today when I lucid dream, sometimes I do fun things like walk through walls. Unfortunately, I don’t have lucid dreams very often—only about five or 10 times a year.

Does lucid dreaming have potential applications beyond physical activities?

Yes. Many people have successfully used lucid dreams to help stop nightmares. People whose work requires creativity or problem solving can benefit from practicing those skills in dreams. Companies have hired me to do workshops on how to become more creative through dreams. One lucid dreamer I studied works as a video game programmer. Before he creates a game, he dreams about it. He’ll dream about monsters and play with them in the dream to see how they respond. He uses his dreams as a simulator for his day job.

Are there pharmaceuticals that can help people lucid dream?

If we had a pill that allowed people to have lucid dreams, everyone would want to take it, because lucid dreaming is fun. There’s no pill at present, but researchers are looking at several substances that might encourage lucid dreams. Stephen LaBerge, who’s the most prominent lucid-dream researcher, did a study using a substance called donepezil, and it seemed to increase the frequency of lucid dreams.

If I dream about doing crunches, will I develop killer abs?

Yes and no: You won’t really get a six-pack just by dreaming, but research shows that envisioning yourself doing exercises can make specific muscles stronger, so you should get a stronger belly than if you didn’t dream about crunches. In general, if you want to improve in waking life, dreams are the perfect place to do it.

Does that apply to tasks like delivering a speech?

You can rehearse any skill in a lucid dream. There’s no empirical evidence that dream rehearsals improve speeches, but anecdotally I know of people who prepared for important presentations with them.

How to Lucid Dream Taking control of what’s happening in a dream can be challenging, and few people can do it predictably. But there are ways to increase your ability to lucid dream: 1. Keep a dream journal. When you awaken each morning, write down what you remember of your dreams. 2. Go on a dream diet. Consuming vitamin B complex, peppermint tea, nutmeg, and mustard may encourage lucid dreaming. Meditation may promote it as well. 3. Target the early morning. This is the most fertile time for dreams. Go to bed early and set an alarm for six hours later. When you awaken before dawn, try to stay awake for an hour and plan out a dream. As you go back to sleep, imagine yourself spinning, which may help initiate a dream. 4. Use cues to confirm you’re dreaming. Flip a light switch and notice if the light changes. Touch objects and see if they feel solid. Try flying. Once you’re sure you’re in a dream, take control of the action.Sources: www.lucidity.com and www.luciddreaminghowto.org