Caffeine, Energy Drinks and their Ingredients

By Posted in - Training Info on August 20th, 2013 0 Comments [This post is written by Chris Hoina, CSCS – Athletic Development Coach at Athletic Lab]

If you’re like me, then you probably drink a lot of coffee. I require a morning cup in order to function as a human being should. And I’m not alone; the whole world is addicted to this stuff. But I’ve also noticed a marked increase in the consumption of certain ”˜energy drinks.’ While I don’t consume them all that often, I know others do, and I think that they are worth mentioning in this post along with coffee and caffeine beverages.

I’ve begun to question the efficacy of caffeine, energy drinks and their use during resistance training. During aerobic training, caffeine is thought to prolong endurance by promoting fat oxidation through the mobilization of free fatty acids from adipose tissue and intramuscular fat stores (McCormack & Hoffman, 2012). Translation: consume caffeine before aerobic exercise and you may end up utilizing extra fat during the training session, which may in turn reduce overall body fat percentage (over the course of continued bouts).

A word of caution though, some sugar-free energy drinks can actually have detrimental effects on your training session. Sillivent et al. (2012) found that consumption of a sugar-free energy drink impaired VO2 max during testing sessions, and in a similar study times to exhaustion were no different in sugar-free energy drink and placebo testing groups. Additionally, researchers believe that performance enhancements may only be realized when energy drinks contain a combination of caffeine and carbohydrates, most notably fructose, as it has been shown to increase VO2 maxes (Sillivent et al., 2012). The rationale is such that the carbohydrate and caffeine mix enhances metabolic function while concurrently providing the body with the added energy from carbohydrates.

While caffeine ingestion at moderate doses (3-6mg/kg of body weight) 1 hour before exercise has been shown to enhance performance in cycling, distance running, swimming, and rowing, that doesn’t really reveal much in terms of strength training (Eckerson et al., 2013). Despite this apparent lack of evidence, there is some research to show that caffeine alone enhances the quality of resistance training. In a study testing the effects of 160mg of caffeine ingestion on experienced lifters prior to bench press 1-repetition maximums, results were quite similar and in some cases caffeine ingestion, ”˜Red Bull’ ingestion, and placebo ingestions were nearly identical (Eckerson et al., 2013).

While the previous study appears to discount the efficacy of caffeine in resistance training there are other studies that refute this assertion. One study revealed increases in maximal bench-press strength in trained women, another study discovered increases in peak torque and power during knee extension and flexion, and another showed increases in overall training volumes as a result of caffeine ingestion (McCormack & Hoffman, 2012). You could argue both sides really, however, the mounting evidence is in favor of caffeine consumption. I do think that it’s worth mentioning that a lot of the current studies focus on sugar-free and full-sugar energy drinks and their effects on performance.

I’ve long since thought that energy drinks, pre-workout out supplements and the like are pointless and a waste. Despite my (and others) intuitive feelings on the matter, the supplement industry is booming and pre-workout supplement use does not appear to be waning. I would assume that people favor energy drinks (think: Red Bull, Monster, Redline, etc.) because of their proprietary ”˜energy matrixes’ which typically include a combination of caffeine, taurine, glucuronolactone, amino acids (like BCAA’s), creatine, and sometimes beta-alanine (responsible for that tingly, sometimes annoying histamine reaction) (McCormack & Hoffman, 2012). While these energy matrix-containing energy drinks was shown to improve subsequent training volume and power output during resistance training, the performance gains could be the result of factors other than their proprietary ingredients (McCormack & Hoffman, 2012). Actually, these energy drinks with the inclusion of carbohydrates were revealed in a recent study to improve total number of repetitions performed during the bench press exercise (and implications for other upper body movements) (McCormack & Hoffman, 2012). These findings are interesting and contradictory and they warrant further consideration.

In a study comparing bench press 1-repetition maximums; sugar-free Red Bull and a substitute which contained 160mg caffeine, 2000mg of taurine, and 1200mg of glucunorolactone both failed to show superiority to a substance of 160mg of caffeine alone. In the present study, three beverages resulted in near uniform performances, implying that caffeine, caffeine with an ”˜energy matrix’, and a caffeine-free placebo all have the same effect on 1-repetition maximum performance (at least in the bench press). At this point it is important to note that McCormack & Hoffman (2012) discuss that anaerobic power testing (all out intensity for ~30 seconds) remained unchanged with the inclusion of an energy drink that contained: caffeine, herbal and botanical compounds, yohimbe, evodiamine, hordenine, tyramine, and tyrosine.

While these energy drinks claim to boost metabolism, their claims remain unsubstantiated in many cases, and their ”˜energy matrixes’ have been shown to have little effect on aerobic metabolism during heavy exercise. (Pettitt et al., 2013) It would appear that energy drinks are effective because of their combination of caffeine and carbohydrates. Caffeine alone may not be as effective. Despite this, the ”˜energy matrixes’ contained in many energy drinks may not be contributing at all to performance increases. So the next time you’re considering purchasing an energy drink for its performance enhancing qualities, think again.

Reference:

Eckerson, J. M., Bull, A. J., Baechle, T. R., Fischer, C. A., O’Brien, D. C., Moore, G. A., Yee, J. C. & Pulverenti, T. S. (2013). Acute ingestion of sugar-free red bull energy drink has no effect on upper body strength and muscular endurance in resistance trained men. Journal of Strength and Conditioning Research, 27(8), 2248-2254.

McCormack, W. P. & Hoffman, J. R. (2012). Caffeine, energy drinks, and strength-power performance. Strength and Conditioning Journal,34(4), 11-16.

Pettitt, R. W., Niemeyer, J. D., Sexton, P. J., Lipetzky, A. & Murray, S. R. (2013). Do the noncaffeine ingredients of energy drinks affect metabolic responses to heavy exercise?. Journal of Strength and Conditioning Research, 27(7), 1994-1999.

Sillivent, J., Blevins, J. & Peak, K. (2012). Energy drinks: Ergolytic or ergogenic?. International Journal of Exercise Science, 5(3), 214-222.

Please leave a Comment