Java lovers everywhere joke that they run on coffee. But should you literally run – or lift or cycle or play football – on coffee, too?
Research on caffeine has shown that the stimulant increases exercise performance when taken all by itself, but exactly how caffeine boosts workout power and endurance isn’t definitive. And likely, various mechanisms are at play, says board-certified sports dietician Georgie Fear, with One by One Nutrition in Canada.
For example, caffeine is known to thwart adenosine’s effects on the body. A byproduct of your body breaking down food for energy, adenosine contributes to brain fog and fatigue when it binds to specialized receptors in your body, Fear says. Caffeine blocks those receptors, so, theoretically, caffeine could also block that “I can’t run any farther!” feeling.
Caffeine might also help dull pain since many of the adenosine receptors that caffeine blocks are found in areas of the brain and spinal cord that are also heavily involved in pain perception. In one University of Illinois study, taking a caffeine tablet before exercising significantly reduced how painful cyclists rated their workouts to be.
Caffeine also triggers the body’s release of the feel-good neurotransmitter dopamine as well as beta-endorphins, natural painkillers that can help you push harder with less discomfort, Fear says. In one Journal of Pain study, drinking coffee 24 to 48 hours after exercise cut symptoms of delayed onset muscle soreness – that tight, achy feeling you get a couple days after a super-tough workout – in half.
Speaking of post-workout brews, caffeine may also increase the body’s ability to refill its energy stores following exercise. In one small study, exercisers who consumed carbs and caffeine after a tough workout packed away 66 percent more glycogen – a form of carbohydrate that hangs out in your liver and muscles to fuel intense activity – than those who only ate carbs. Stockpiling your reserves allows you to work out that much harder the next time you hit the gym, but more research is needed to confirm caffeine’s potential effects on recovery.
All caffeine aside, however, coffee may promote exercise recovery through its wealth of antioxidant compounds, says sports dietitian Kelly Pritchett, assistant professor of nutrition and exercise science at Central Washington University and spokesperson for the Academy of Nutrition and Dietetics. While some level of inflammation post-exercise is required to cause your body to adapt and improve from your workouts, excess inflammation can hinder recovery and contribute to overtraining. The natural antioxidants in coffee help to keep those levels in check.
As wonderful as coffee is, however, you can’t drink as much you want whenever you want and expect to get results like those Popeye got from slamming spinach. Here’s what to do instead:
1. Drink in moderation.
Research suggests that you need to consume 4.5 to 6 milligrams of caffeine per kilogram of body weight to maximize your exercise benefits. For a 140-pound woman, that’s roughly 285 to 380 milligrams, or roughly one 20-ounce to two 16-ounce cups of coffee, Fear says. (Every brand, roast and shop offers slightly different amounts of caffeine.) And, in case you’re wondering, even if you’re a heavy coffee drinker and have a tolerance to caffeine, you don’t necessarily need extra coffee to get an exercise boost, according to University of Illinois findings.
If you have a sensitive stomach or aren’t used to drinking that much coffee, start with about half that and see how it goes, Pritchett says, noting that you will likely see a benefit from the smaller servings.
2. Time your order.
Power up one hour prior to hitting the gym, Pritchett says, noting that’s when the vast majority of studies time pre-workout caffeine. However, it’s possible that coffee can boost recovery when consumed following exercise, so go ahead and give it a shot – as long as that doesn’t mean drinking coffee too close to bedtime. Caffeine consumed within six hours of bedtime can significantly affect sleep quality in most people, Fear says.
3. Dress it up.
While it’s always best to minimize intake of added sugars and artificial sweeteners, you don’t have to order your coffee black. Milk doesn’t seem to blunt the athletic boost you’ll get from the coffee – and it may actually aid in performance and recovery through its combo of carbs and protein, Fear says. Pre-workout latte, anyone?
Written for USNews.com