A little pink in your drink might just improve your running, new research from the UK suggests. The small study found that people ran faster and longer on a treadmill when they first rinsed their mouths with an artificially sweetened pink-coloured drink, compared to rinsing with the same beverage without colour. The findings reinforce the potential power of the placebo effect for athletic performance.
Dating back to the early 2000s, many studies have shown effects on athletic performance from something known as carb-rinsing. Put simply, when people swish around and then spit out a drink filled with carbohydrates before exercising (meaning they can’t get nourishment from it), they’re likely to perform slightly better and experience less fatigue than if they had drank nothing or just water. Not all studies looking into this effect have found a benefit from carb-rinsing, but a 2014 review found that the vast majority of studies did show a clear if small improvement in exercise performance.
One leading theory for why carb-rinsing works is that the carbs activate receptors in the mouth that send a signal to the brain, essentially tricking it into thinking that the body is getting extra fuel and allowing our muscles to work a bit harder. For really strenuous exercise or athletic competitions, people are probably just better off ingesting the carbs, but swishing has become a common practice among runners and athletes to help them gain a small edge.
Study author Sanjoy Deb, a sports and exercise nutritionist at the University of Westminster’s Centre for Nutraceuticals, and his team wondered if our expectations alone could also boost our ability to exercise. The findings were published Wednesday in Frontiers in Nutrition.
“As we know that the sweet taste of sugars is linked with an improvement in exercise performance, we wanted to see if this perception that a drink was sweet would have a similar response,” Deb told Gizmodo in a email.
The team recruited 10 healthy and relatively active volunteers for their experiment, which took place over several weeks. The volunteers learned about the possible benefits of carb-rinsing and then were asked to test out what they thought were two commercial sports drinks. In reality, both drinks were low-calorie and artificially sweetened, with the only difference being the pink colouring added to one. On two different occasions, the volunteers rinsed with the clear or pink drink then ran on the treadmill for 30 minutes, only being told to stay at a consistent level of effort.
Overall, the runners’ performance (measured by the speed they chose and how far they ran) improved by 4.4% when they drank the pink beverage, compared to the clear version. They also reported feeling more enjoyment during running. The findings are based on a very small sample size, of course, so shouldn’t be seen as definitive. But Deb and his team think their research shows the potential benefits of intentionally invoking the placebo effect — the phenomenon of experiencing positive health benefits from something with no physiological influence.
“The concept of the placebo effect is not new. Still, the challenge is: how can we capitalise on the placebo effect when formulating new products and appealing to our sensory perception?” he said. “Colour, taste, and smell all have potential, but it is an area of research largely unexplored.”
To that end, Deb and others at the Centre for Nutraceuticals plan to keep studying “how the colour of functional foods/beverages and supplements can have an impact in different situations.” It’s possible, for instance, that the research conducted by scientists like Deb could one day help create or improve drinks that help new runners get through their growing pains by making the effort more enjoyable.