- The authors of a recent, small-scale study concluded that pink-dyed beverages might help people exert greater effort and feel better during exercise.
- Their study is the first of its kind to measure how a drink’s color can affect exercise performance.
- They concluded that sweet, no-calorie pink drinks might help people work out faster and longer, as well as increasing feelings of pleasure during running, compared with clear drinks. However, confirmation in much larger studies is required.
A team of scientists from Loughborough College and the University of Westminster, both in the United Kingdom, reported the results of their study in the journal Frontiers in Nutrition.
One of the authors, Dr. Sanjoy Deb, a lecturer and practitioner in sport and exercise nutrition at the University of Westminster, says:
“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.”
Earlier research has indicated that rinsing the mouth with carbohydrates can reduce the perceived intensity of exercise.
This so-called ergogenic effect seems to occur because the mouth detects sweetness and, therefore, anticipates carbohydrate consumption.
The expectation appears to impede signals that drive feelings of fatigue. It also activates the brain’s reward and motor function area, elevating arousal and pleasure during exercise.
The current study’s authors wanted to investigate whether swishing a sweet, colored drink with no carbohydrates could induce a similar effect.
The scientists selected pink due to its association with perceived sweetness and expected carbohydrate consumption. This perception, the authors explain, “is consistent across European, Asian, and American cultures.”
In a pilot study, which preceded the experimental trials, the authors showed that participants preferred a pink solution over a clear one. They perceived the pink drink as sweeter and tastier than a clear drink.
Researchers held one preliminary and two experimental trials 1 week apart. They used a self-paced protocol based on previous research involving carbohydrate mouth rinses.
Ten healthy, active participants — six male adults and four female adults — voluntarily participated in the study. They were aged 27–33 years and ran weekly as part of their training.
Each began their trials at the same time of day, following a meal. During the trial, they only consumed water for hydration.
While the participants could see the color of the drinks in the experimental trial, they were unaware that the liquids had no carbohydrate or nutritive content. They exercised on a treadmill for 30 minutes during each trial.
While exercising, they rinsed their mouths with a clear or pink, noncaloric, sweetened drink. Each solution comprised 0.12 grams of pure sucralose in 500 milliliters of plain water. Sucralose is a noncaloric artificial sweetener.
The clear solution contained no added dye, whereas the pink solution included two drops of colorant. The scientists collected performance, perceptual, and physiological data on the participants throughout the trials.
Participants who drank the pink drink ran 213 meters (698.8 feet) farther and increased their mean speed by 4.4%.
They reported experiencing enhanced feelings of pleasure, an indication that they enjoyed running more. The pleasure ratings increased from 3.4 with the clear liquid to 3.8 with the pink drink.
In a post-trial interview, all participants reported that the pink solution was sweeter.
Although six participants thought that they ran farther after having the pink drink compared with the clear drink, only five did run farther.
Unlike many previous studies that investigated the effect of mouth rinses on performance, these findings highlight how the color of a mouth rinse might influence exercise performance.
The researchers believe that their work blends “the art of gastronomy with performance nutrition.” Adding a pink dye to a sweetened, nonnutritive beverage increased the perception of sweetness, “feel-good” emotions, speed, and distance.
The authors outline several limitations to the study. Most importantly, they only included a very small number of “habitually active” individuals in the trials. The participants were also within a limited age range of relatively young adults, so the findings might not apply to other age groups.
Another potential drawback is the lack of control over the menstrual cycle of the female participants in this study. Some researchers have
The study’s authors hope that future research will further examine correlations between a mouth rinse or drink’s color, perceived carbohydrate intake, and psychophysiological outcomes.
They explain that such investigations should seek to determine whether the color of a mouth rinse or drink can alter perceptions of fatigue during “ecologically valid performance time trial events.”