Will Coffee Help Me Run Further And Faster?

Recently whilst out for a sunday run along the River Thames, I experienced that surge of endorphins familiar to most people who enjoy sport and exercise. I felt like I could have kept going for hours. I'm not a particularly strong runner by any stretch of the imagination, so I was interested in why today I felt like my body was custom built for it. After a little bit of research into this, it seems that it was quite likely to have been the double espresso I drank around an hour before I left.

My pre-run coffee definitely sparks more enjoyment, focus and performance. No real surprises there to any coffee drinkers, but is this just a placebo effect? And can a cup of coffee before a run do any harm?

Like all drugs, there are some negative effects, but many studies have shown that at low doses, caffeine is safe. At high doses you can experience irritability, increased heart rate, headaches, tremors and difficulty sleeping. It can act as a mild diuretic causing increased urine production, but contrary to popular belief, research has shown that it doesn't cause dehydration. 

It is also considered safe by the World Anti-Doping Agency (WADA) and therefore is not on the list of prohibited substances. Olympic athletes certainly seem to love it. A study in 2011 tested for caffeine in the urine of over 20,000 Olympic athletes that competed between 2004 and 2008. The researchers found that 3 out of 4 athletes had consumed caffeine just before or during competition, with endurance sports showing the highest levels of caffeine concentration. This begs the question, is this to enhance performance?

Quite probably. It's effect on athletes is overwhelmingly positive, as borne out by the wealth of research that looks at caffeine and performance gains. In runners, cyclists, rowers, swimmers, tennis players the studies keep demonstrating beneficial effects. A meta-analysis by Doherty and Smith in 2005 reported that when compared to placebo, caffeine improved performance by 11% in well-trained amateur endurance runners. That is a huge gain.

Why does caffeine have such a positive effect on performance? Well there are a number of different opinions on this. Firstly it's likely that caffeine makes calcium more readily available for use by the skeletal muscles. This makes muscles more powerful. Secondly, it increases levels of adrenaline in the blood which stimulates an increase of available fatty acids from fat and muscle. Muscles may use this as an energy source whilst sparing glycogen, which can then be used later on in exercise. Thirdly, and arguably most important of all, is the effect on the central nervous system. It seems that caffeine increases nerve transmission and blunts perceived exertion, which means you can run faster and for longer distances without feeling exhausted.

Okay so if you do decide to take caffeine before you run, how much do you need? It seems perfect for coffee lovers as you only need one cup of strong coffee around an hour before exercise. The research shows that 3mg of caffeine per every kg of body weight (3mg/kg) is enough. For example if you're a 60kg athlete then the optimal dose is 3mg/kg = 180mg caffeine = 1.8 shots of espresso. And if you're thinking more is better and maybe you should drink 2 or 3 of these before a race, well don't. It has no additional benefit on performance and may also bring on some of the negative effects of high doses as mentioned earlier.

In summary, the evidence shows that  a cup of coffee before a run does have a beneficial effect on exercise performance that is not from placebo. All of this being said, the health effects of coffee can differ from person to person, and high doses do have risks. Therefore it's worth consulting with your doctor to make sure it's a good choice for you. Lastly, please choose when you take your "coffee run" carefully. If you train in the evening, then think twice about the benefits, as sleep deprivation has such well-proven negative effects on performance and lifestyle that in the long run you may wish you chose a decaf.

Tom Lowes B.Ost MSc (Sports Med)
Registered Osteopath - Sports Injury Rehabilitation

Twitter @SportsMedOsteo