Study: caffeine reduces pain perception and perceived exertion while running

While you know your morning java helps you jump-start your day; you may even know that it’s a legal performance enhancer. But you may not know what the science behind that boost is–and whether it can carry over to race day. A new study published in  Nutrients Journal evaluated the impact of caffeine on endurance running performance and prolonging time to exhaustion, and the results may have more of us reaching for an espresso before toeing the line.

The study

The athletic community all agree on the performance-enhancing benefits of caffeine, with World Athletics even recommending it as a performance enhancer. However, most of the evidence for this was established using laboratory-based studies on cyclists. Researchers set out to determine what impact caffeine had on endurance runners, conducting a meta-analysis of 21 separate randomized controlled studies.

The boost caffeine gives is called an ergogenic effect, meaning it elevates energy, performance and recovery. This review focused on time to exhaustion and time to complete a given distance, and researchers acknowledged that more research is needed on the impact of caffeine on women, since the available information heavily is based on male runners (only 7.5 per cent of participants were women). More than two-thirds of the athletes in the studies were recreational, with a third competing at a more advanced level.

The takeaway

Caffeine intake showed a meaningful ergogenic effect in increasing the time to exhaustion and improving performance in running time trials, leading researchers to conclude that caffeine has the potential to be used as an aid for endurance running events. Researchers observed that caffeine may “inhibit perceptual response during exercise” meaning participants had an increased ability to tolerate discomfort associated with fatigue while running.

While more evidence is needed to establish the best effective dose for runners, it’s safe to say caffeine as a performance-enhancing supplement for all running distances is here to stay.