As far as performance-enhancing supplements go, the simplest and most common products are often the most effective. Whether it’s baking soda, carbohydrates, or caffeine, time and time again the old standards seem to outperform anything else on the market. So it’s no surprise at all that energy drinks are popular among athletes, since they combine both caffeine and carbohydrates.


In a study this month in the Journal of Strength and Conditioning Research, energy drink use was put to the test as an ergogenic aid for endurance exercise. Often, when a study is performed on ergogenic aids, it concerns only an individual substance. For example, a study may be done on just carbs or just caffeine, or it may compare the two, but energy drinks contain a number of ingredients that are beneficial when it comes to athletic performance.


One of the primary benefits of energy drinks is the stimulation provided by caffeine. Caffeine and exercise have similar effects on the body, and when you combine the two you can exercise longer and faster. Another factor in the purported effectiveness of energy drinks is carbohydrate availability and utilization. By consuming a beverage with carbohydrates before your workout, as you do when you drink an energy drink, you’re adding fuel for the body to burn. This approach seems to work particularly well for shorter duration endurance activities. Energy drinks are said to influence immune response and inflammation as well, and both of these effects would also benefit performance. The B vitamins in many energy drinks, particulary niacin, are also said to assist energy production. 


With all these beneficial ingredients in one beverage, it seems like energy drinks must be a slam dunk when it comes to improving performance. Indeed, in their preliminary research, the researchers in this study found that carbohydrate and caffeine ingested together were an even better ergogenic than either alone. It’s an air tight combination - or so it would seem.


However, beyond the preliminary work, the results of this study were the opposite of what the researchers expected. They compared Red Bull to cola (which only contains carbs and caffeine, without the other energy drink ingredients), and compared both beverages to a placebo. Neither of the drinks improved performance more than the placebo did. To make matters even worse, both cola and Red Bull increased stress response. This effect was worse with the energy drink than it was with cola. Finally, the rate of fat burning was highest in the placebo.


The researchers admitted it was difficult to explain these results, but there were some oddities in the study design that might have had something to do with it. For one thing, the athletes consumed the drinks nearly an hour before exercise, which caused low blood sugar in those who were consuming the cola and energy drinks. Also, the cyclists in the study had all been consuming caffeine daily, which probably had a significant effect on how they responded to the caffeine in the energy drinks and cola.


In the end, it seems if you already have a caffeine habit, more caffeine and an added sugar spike before a workout might not have much benefit. However, conclusive evidence would require a larger study group and more diverse circumstances.



1. Melody D. Phillips, et. al., “Pre-exercise energy drink consumption does not improve endurance cycling performance, but increases lactate, monocyte and IL-6 response,Journal of Strength and Conditioning Research, DOI: 10.1519/JSC.0000000000000275.


Photo courtesy of Shutterstock.

See more about: ,