Caffeine and Exercise

By Sarene Alsharif, MPH
Caffeine and Exercise

Caffeine is the No. 1 most socially acceptable and frequently used drug. Yes, caffeine is a drug. More specifically, it's an ergogenic aid, meaning caffeine helps the body perform better during physical activity. The 2014 Perceived Exertion Laboratory Manual reports the ergogenic effect of caffeine occurs because it changes a person's perception of how much effort an individual puts forth while exercising. In other words, caffeine gives exercisers a boost in energy so they push themselves harder.

What is Caffeine?

Caffeine occurs naturally in some seeds and plants, the most common being coffee beans and cacao beans. Historically, people have consumed caffeine mostly through coffee and tea, but manufacturers have started producing it chemically and adding it to numerous drinks and foods for its physical and psychological boost. Most people are familiar with energy drinks, which reduce fatigue and improve performance. And, many individuals now consume caffeine pre-workout, predominantly through energy drinks or gels, to reap the benefits of a more exerting workout.

How Does it Work?

Caffeine improves both endurance and resistance training. The Limits of Human Endurance, published in 2013, explains that caffeine increases dopamine in the brain, especially in the areas related to focus, vigilance and perception of fatigue. The Journal of Sports Sciences published a study in 2012 reporting inactive men bicycled harder when they had consumed caffeine than when they did not have any caffeine; but in both cases the men felt like they had exerted the same effort. And a 2005 study in the Scandinavian Journal of Medicine & Science in Sports found the same: Researchers concluded the effect of the caffeine in the participants' brain made them feel like they did less work when consuming caffeine, but, in reality, they actually exercised harder.

How Much Caffeine is Healthy?

A healthy adult can safely consume 300 to 400 milligrams of caffeine or about 3 to 4 cups of brewed coffee a day. A shot of espresso has about 75 milligrams of caffeine and energy drinks range from 47 to 163 milligrams of caffeine per 8 ounces.

Used properly and within the recommended amounts, caffeine can have positive outcomes. Enjoying a caffeinated beverage before hitting the gym does have its benefits, but it is important to make wise choices. For example, consider ordering a 12-ounce low-fat latte before a workout. At 120 calories with 10 grams of protein, 75 milligrams of caffeine and naturally occurring sugars, a latte can be a healthy pre-workout boost.


Reviewed by Sharon Denny, MS, RDN

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