Running may be hard on your smile, but it turns out that the feeling is not mutual. In fact, smiling while running has been a common trick that runners use to try to improve their performance. This has long been considered just a piece of runners’ lore, almost superstition. But now science confirms that it’s true: smiling makes you significantly more efficient at running. In fact the benefit is comparable to months of difficult conditioning techniques.

A young couple running and smiling together in Burke, Virginia

Measuring the Smile Effect for Runners

In this new study, published in the journal Psychology of Sport and Exercise, researchers tried to measure the impact of smiling, frowning, and relaxation during running. They wanted to see how these different states affected running economy, perceived effort, and emotional state.

To test the effects, they had 24 trained runners complete four 6-minute running blocks at 70% of max running speed and with their breath straining at maximum capacity. Runners rested for two minutes between blocks. During each block, they were told to do one of the tested running states or just focus on running (the control condition). The order of blocks was randomized for each runner.

Smiling made runners significantly more efficient than frowning or focusing. Although the difference wasn’t statistically significant between smiling and relaxing, 14 of the runners were most efficient when smiling, but only one was most efficient when consciously relaxing. Perceived effort was highest when frowning. Muscle activation was also highest when frowning.

How Big Is the Effect?

Getting a measurable improvement in running efficiency is huge. Any improvement in efficiency can be a big deal, but the actual size of the effect is impressive: 2%. That’s right, runners were able to reduce their oxygen consumption by 2% doing nothing more than smiling.

We can compare that to other attempts to improve running efficiency. In one study six weeks of plyometric training (“jump training) failed to produce noticeable improvement in runners. Similarly, heavy weight training had an uncertain effect on runners, although women achieved an improvement in efficiency of 1.2%. Given the choice between weeks of doing weights, jumping, doing both, or just smiling, which would you choose?

Is Your Smile Ready for the Course?

In discussing the results of this study, runner/researcher Alex Hutchinson talks about the “bright” smile of Eliud Kipchoge during the Breaking2 marathon. The goal of this marathon project was to break the two hour marathon barrier, which would represent running 2.4% faster than the fastest marathoner ever. Smiling was a deliberate strategy he used, and it almost worked: he fell short of the goal by just 25 seconds.

But for some people, the effort of smiling is not as easy as it seems. It’s not as simple as just telling yourself to smile when you’re unhappy with the appearance of your smile. Then it becomes a complex negotiation of fear and uncertainty.

However, you don’t have to be trapped by an unattractive smile. You, too, can be free to have a smile that you are happy to share on command, whether you’re running, in a job interview, or just out with friends when someone pulls out their phone.

If you would like to learn how a smile makeover in Fairfax County could make  you more comfortable and confidence in your smile, please call 703-323-8200 today for an appointment with cosmetic dentist Dr. Pamela Marzban in Burke, VA.