Monday, September 17, 2012
Pouring Water on Sports Drink Health Claims
The success of the energy drink industry is evident in runners clutching bright bottles but experts are questioning their use
There are many strange sights in the world of running but one of the daftest must be the beeline so many runners make for a Portaloo or the nearest back wall after just a few miles of the marathon.
Despite all the advice given about not over-imbibing in the hours before the start, it seems there are always runners who can’t resist downing fluids in unfeasible quantities. And since what goes in must come out, the answer to nature’s call ends up being a premature one.
Another odd sight is that of joggers, and walkers, in even short races trudging around the course with vials of lurid-coloured fluids held in their hands or stored in a belt. This in spite of the fact that nearly every race these days offers drinks of various hues to participants along the course.
Why would anyone carry more fluid than they had to, either in their bladder or in their hands, during a race unless they believed that hydration was paramount? I believe these phenomena demonstrate the now widely held belief that sports drinks significantly enhance performance and recovery.
Runners these days load up on fluids before, during and after their bursts of activity, treating the local 5km as though it were a trans-Saharan epic.
I always had my doubts about the fad for such drinks. It helped that a few sips of water suffices to take me 10 miles and more on the average temperate Irish day.
Yet even I started to feel inadequate as the drumbeat from the sports drinks industry grew louder and their scientific recommendations multiplied. All that talk about replacing electrolytes and boosting recovery started to seem convincing and it was hard to avoid the free samples so generously distributed at races.
Yet I also observed how the popularity of sports drinks spread from the elite athletic community to hack runners like myself.
Then I started noticing how many runners were consuming these high-sugar, high-salt concoctions regularly, and not just when exercising. Energy drinks had become a lifestyle choice, an overt signal by those consuming them that they were leading a healthy existence.
It was almost as if the consumption of sports drinks obviated the need for sport itself – a bit like wearing a tracksuit in the house. Except that tracksuits don’t contribute to the spread of obesity.
Doubting the propaganda about sports drinks was a lonely business, a bit like questioning the merits of the property boom during the Celtic Tiger years.
But then this summer, the British Medical Journal ran no fewer than seven articles attacking the industry.
In a brave and devastating critique, the BMJ questioned the claims made for sports drinks, cast doubt on the reliability of research put forward in support of these claims and investigated the financial ties between the makers of the drinks and sports associations, medical groups and academic researchers.
The industry has long relied on two central claims to drum up business. It tells us that thirst is an unreliable guide for deciding when to drink, and claims that boring old water is inferior to sports drinks for rehydration.
The companies claim that the sodium in sports drinks stimulates thirst, resulting in the consumption of a higher volume of fluid and better retention compared with drinking water.
Their case has been helped by the decision of the European Food Safety Authority to uphold claims that sports drinks hydrate better than water and that they help maintain performance in athletes doing endurance exercise.
However, the BMJ says the authority relied on industry-funded research in coming to these conclusions which, in any case, applies to elite athletes rather than the ordinary person going to the gym.
Its research looked at 431 performance-enhancing claims in adverts for sports products and found that only three of them were of high quality. It reviewed the evidence underpinning the products and found that many studies had small sample sizes, were poorly designed and manipulated conditions (by, for example, starving participants before testing) in a way that could affect the results.
The study also took issue with the claims that the colour of your urine is a good indicator of hydration levels, saying there was no evidence for this. Despite all the guidance about the dangers of dehydration during exercise there is no evidence that anyone doing a marathon has ever died from it, a Harvard medical professor is quoted as saying. In contrast, hyponatraemia – over-hydration – is a genuine disease associated with sport which has been responsible for 16 deaths during marathons.
Not surprisingly, the industry took issue with the BMJ’s findings. GlaxoSmithKline for example, which makes Lucozade Sport, said it disagreed with the conclusions.
“Over 40 years of research experience and 85 peer-reviewed studies have supported the development of Lucozade Sport and all our claims are based on scientific evidence that have been reviewed and substantiated by the European Food Safety Authority.” There, for now, the controversy rests. No doubt fans of sports drinks will continue to down the funny-coloured fluids while sceptics like me stick to H2O. Maybe what matters most is that we keep on running.
By PAUL CULLEN@irishtimes.com