- A study suggests that the effectiveness of sports drinks may depend in part on their color.
- Runners who rinsed with a pink liquid ran better than those who consumed the same but colorless drink.
- Improvement in their performance is likely due to a placebo effect.
The “placebo effect” is real. It’s the name for a strange phenomenon that most notably occurs during clinical trials. People who are given an inactive substance, like a sugar pill, often experience the same therapeutic benefit as those who are given actual medicine. It’s not their imagination — it really happens. (Even better, recent research suggests that therapeutic benefits occur even when the person knows that they were given a placebo.)
Now, a new study from the University of Westminster (UOW) Centre for Nutraceuticals in London and published in Frontiers in Nutrition suggests that the placebo effect may explain yet another phenomenon: Athletic performance.
The research showed that treadmill runners who rinsed their mouths with a pink liquid increased their performance over runners who swished with exactly the same liquid but without the coloring. Why pink? The color is generally linked to sweetness, and the researchers wondered if that association would subconsciously trick the runners into an expectation of more carbohydrates and thus energy.
Author Sanjoy Deb explains:
“The influence of color on athletic performance has received interest previously, from its effect on a sportsperson’s kit to its impact on testosterone and muscular power. Similarly, the role of color in gastronomy has received widespread interest, with research published on how visual cues or color can affect subsequent flavor perception when eating and drinking.”
Running for science
For the study, the researchers recruited ten healthy adults — six men, four women. All were regular exercisers, with an average age of 30. The participants were told that they would be testing the relative benefits of two commercial sports drinks after watching a brief video explaining the value of such beverages. Previous research found that mid-exercise rinsing with such drinks can reduce the perceived intensity of exercise.
The drinks consisted of 0.12 grams of sucralose dissolved in 500 mL of plain water — an artificially sweetened rinse low in calories. The liquids contained no other additives common to sports drinks such as caffeine. The pink version had non-caloric coloring added but was otherwise identical.
After a 12-minute warmup phase of jogging followed by running, the athletes ran at a difficult pace for 30 minutes, rinsing with their drinks as they ran. Following a brief cool-down, they were interviewed to capture their impressions of the exercise session. (Each runner tested both drinks.)
The researchers found that when the volunteers used the pink rinse, they ran an average of 212 meters farther and 4.4 percent faster. They also enjoyed the exercise more.
Deb said, “The findings from our study combine the art of gastronomy with performance nutrition, as adding a pink colorant to an artificially sweetened solution not only enhanced the perception of sweetness, but also enhanced feelings of pleasure, self-selected running speed, and distance covered during a run.”
The researchers also plan to dig deeper into the phenomenon by investigating the possibility that the pinkness of the beverage is somehow directly activating the brain’s reward areas.