In one study, two groups of healthy volunteers signed up to perform some "damaging eccentric exercise" and have their level of pain intensity measured by researchers, who were presumably wearing scary clown masks. One group was given caffeine capsules equivalent to drinking two-and-a-half cups of coffee, while the other group was given placebo pills. At the end of the series of exercises, the researchers found a significant increase in the level of pain tolerance of those subjects who took the caffeine pills. The subjects also reported feeling more able to perform everyday activities like walking, sitting, climbing and descending stairs, otherwise known as all the shit you can't do the day after a suicidal workout without sobbing uncontrollably.
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"Working out is obviously bad for you."
Holy crap, the ads were right! Mountain Dew really can let you do extreme sports! Or, at least make you feel less like shit the next day.
And, in fact, if you're less the "damaging eccentric exercise" type and more the "sit your ass in front of a computer screen" type (hey, we know where you're coming from), there's still good news for you. In another study, scientists had volunteers perform 90 minutes of fake computer tasks similar to the everyday tasks you might perform at an office -- tasks meant to generate pain in the shoulders, neck, forearms and wrists of the volunteers. Before the start of the experiments, scientists allowed the volunteers to drink coffee ... not to study the effect of coffee on pain, but "to avoid unpleasant effects of caffeine deprivation, e.g. decreased vigor and alertness, sleepiness, and fatigue."
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