What is it about Gatorade that has athletes so hooked? Is it the taste? The feel of an ice-cold beverage quenching their thirst? An increase in performance? Or could it possibly be the amount of sugar that makes up these drinks? Scientists at the University of Birmingham carried out a series of experiments1 that offer some insight as to how the sugary component of the drink may be linked to improvements in performance.
In one study, two groups of cyclists were timed for a 40 km bike ride. One group was given a drink filled with carbohydrates and electrolytes (much like Gatorade) and the other group got a regular drink with nothing added to it. The group that drank the Gatorade-like drink actually finished the time trial about a minute faster than the other group- a 2.3% improvement in performance.
The results of this study, along with previous work done on this topic, led many researchers to conclude that the best performance improvements occurred when athletes drank a Gatorade-like drink while involved in high-intensity exercise lasting about an hour. Due to the time frame that these results appeared, researchers also concluded that the improvements were most likely not related to the actual energy (carbohydrates) in the drink getting to the working muscles.
So, if the drink is not fueling the muscles within this time frame, what is causing the improvements in performance? One of the researchers from the initial study teamed up with three different researchers and came up with an interesting idea. The same basic setup would be used to test cyclists in a 40 km timed trial. Only this time around, the athletes would not actually drink anything. Instead, one group of cyclists would get to gargle a Gatorade-like drink while the other group would get to gargle a plain drink with nothing added. Guess what they found. The athletes in the Gatorade-like group performed better than the group who gargled the plain drink. In fact, the Gatorade-like group improved their performance by 2.8%, not far off from the 2.3% improvement gained by those who actually swallowed the drink.
It appears as though athletes can have the same boost in performance without actually drinking any of the sugary drink. All it takes is a quick mouth rinse. But how is this possible?
Another set of researchers located in Birmingham decided to see what exactly was going on in the brain that may explain the improved performance. These researchers took brain scans of people as they rinsed their mouth with either a real sugar drink or an artificially sweetened drink (think Coke versus Diet Coke, but not as tasty). There was no taste difference between the two drinks. Even though the athletes could not tell the difference between the two, their brains showed higher levels of activation in reward areas such as the nucleus accumbens and orbitofrontal cortex when they rinsed their mouths with the real sugar drink.
The explanation behind this is that there appears to be carbohydrate receptors in the human mouth that respond to foods regardless of how they taste. Although both drinks tasted sweet, the carbohydrate receptors only picked up on the presence of the real sugar drink. Once these receptors pick up on the presence of carbohydrates, a sensory signal is sent to the brain telling it that calories are coming its way. This type of signal creates a response in the reward areas in the brain. Even though the carbohydrates that initiated the reward response in the brain are spit out, the signals have already been sent and received, and the brain responds without the calories ever being consumed.
The theory is that the athletes who received the reward response from the brain improved their endurance because the reward areas were activated while exercising. Even though the athletes were not consciously aware of the response taking place in the brain, they were able to exercise harder than their counterparts.
The next time you find yourself reaching for a huge bottle of Gatorade, remind yourself you can do just fine with a quick rinse.