Smiling can improve running economy and reduce perceived effort

Just saw this RunSmarter summary of research (full paper) about how smiling while running helps improve running economy and reduce perceived effort. Something to think about when doing workouts and racing.

Effects of Facial Expression During Running

Study Design:

The primary aim of this 2017 study by Noel Brick & colleagues was to determine the effect of brief alterations of facial expression on movement economy, physiological, and perceptual responses during running.

24 trained runners completed four 6-minute running blocks at 70% of velocity at VO2max with 2 min rest between blocks. Running blocks included:

  • 1.) Smiling
  • 2.) Frowning
  • 3.) Consciously relaxing hands & upper body
  • 4.) Normal attentional focus (Control)

The order of each block was randomised to each participant.

Cardiorespiratory responses were recorded continuously and participants reported perceived effort after each condition.


Running Economy:

Mean VO2 was lower during smiling than frowning and control. A small reduction in VO2 was noted during smiling in comparison with relaxing, but this did not reach statistical significance. Fourteen participants were most economical during smiling, five during frowning, and four during control. Only one participant was most economical when relaxing

Heart rate:

No differences in heart rate were noted between conditions.

Perceived effort:

Perceived effort was higher when frowning than both smiling and relaxing. There were no differences between any other pairs of conditions

These findings suggest that smiling may improve running economy and reduce effort perception during running. In contrast, frowning may increase effort perceived and activation during endurance activity.


During a recent 5k, I decided to try a combination of smiling, relaxation and gratitude as part of my mental approach. I found that these three things all helped reinforce one another and I ran a PR pace at a lower perceived effort. Thanks for sharing this, Adam!