Athletes who consume energy drinks to give them a competitive edge might in fact get a boost in energy, but could pay for it later.
Researchers at Camilo José Cela University (UCJC) say they found athletes who use energy beverages were more likely to report insomnia and nervousness in the hours after the competition.
In the 4-year study, athletes in a variety of vigorous sports consumed the equivalent of 3 cans of energy drink or an energy drink placebo before a sports competition. Sporting performance was measured with the use of GPS devices that determined the distance and the speed at which athletes moved.
The researchers also employed other sophisticated equipment to measure muscle performance. Published in the British Journal of Nutrition, the results show that athletes who used energy drinks increased their sporting performance by between 3% and 7%.
Juan Del Coso Garrigós, one of the study authors, says energy drinks do in fact make basketball players jump higher, increase muscle force and power for climbers and trained individuals, swimming speed for sprinter swimmers, hit force and accuracy for volleyball players and the number of points scored in tennis.
Insomnia and nervousness
That's the good news. But once the sport competition is over, it isn't exactly back to normal.
These studies asked athletes about their sensations after consuming the energy drink and measured the frequency of the side effects in comparison with the placebo drink.
"Athletes felt they had more strength, power and resistance with the energy drink than with the placebo drink," said Del Coso. "However, the energy drinks increased the frequency of insomnia, nervousness and the level of stimulation in the hours following the competition".
Maybe it shouldn't come as a surprise that the consumption of energy drinks produced an increase in the side effects typically found with other caffeinated drinks. The researchers said they found no significant differences between male and female athletes in the perception of positive sensations, nor in the apparition of side effects.
"Caffeinated energy drinks are a commercial product that can significantly increase sporting performance in many sports activities," said Del Coso. "The increase in their consumption is probably driven by the hard advertising campaigns of energy drink companies related to sports sponsorships."
Not that much energy
Energy drinks are made up of mostly carbohydrates, caffeine, taurine and B vitamins. From brand to brand, there is little difference in the quantities and ingredients.
Despite being labeled as energy drinks, the researchers say they don't really provide more energy than other soft drinks. Instead, they have an 'energizing' effect, due mainly to the caffeine they contain.
Del Coso maintains that none of the other ingredients in energy drinks actually produce a significant effect on physical or mental performance.
The average energy drink can contain from 75 to over 200 milligrams of caffeine per serving. Health experts at Brown University say this compares to 34 milligrams in Coke and 55 milligrams in Mountain Dew.
If the beverage is labeled “no caffeine,” the energy comes from guarana, which is the equivalent of caffeine. The Brown experts note that 5-hour energy advertises “no crash,” but says this claim is referring to no “sugar crash” because the drink has artificial sweetners.