I’m super excited to be invited to contribute to this blog. Nutrition for cycling (and more broadly endurance sports) has moved forward in leaps and bounds in the last ten years, on the back of some incredibly well conducted research in the UK, Canada, South Africa and Australia. It’s challenging the way sports scientists and dietitians think about nutrition, fatigue and performance. The Ironman triathlon scene is already starting to see the benefits, and pro cycling is starting to head in the same direction. Hopefully my contribution to CyclingTips can help translate that research into meaningful strategies for cyclists, from the weekend rider through to elite club racers.
One of the first things I always get asked is as a sports dietitian is “what supplements should I take?” But what really gets me is that everyone wants to know about supplements without even considering what they’re eating for breakfast, lunch and dinner. Fruit and yoghurt isn’t a sexy recovery snack compared to ionised whey protein isolate and a PowerBar.
Research shows us that at least two thirds of athletes use sports foods or supplements. One study of Australian Institute of Sport found 98% of swimmers took some form of sports food or supplement. The most commonly used are multivitamins, sports drinks and protein powders.
One of the most interesting things is that while most athletes use supplements, many don’t actually know what they’re taking or why. In one survey 40% of elite Australian athletes could not correctly identify the active ingredient in the supplements they were taking. 45% weren’t aware of the potential side effects, 47% didn’t know how the supplement was meant to work, and almost half didn’t even know what the recommended dose was!
As an example of this, in a survey of British athletes only 63% of those trying to increase strength took creatine monohydrate and only 56% took whey protein (both have been consistently shown to work). Yet 76% took Vitamin C believing it would enhance their training. Not only is there no evidence for this, there’s research to suggest that large doses of Vitamin C REDUCE performance.
These figures raise the question of where on earth are athletes getting their supplement advice, given that so many get it wrong? In my experience the cycling community get their info from coaches, soigneurs, fitness trainers, other cyclists, magazines and the internet. There’s plenty of people willing to give nutrition advice, but be aware that they’re not always qualified to do so, and may not be up to speed with the latest research (as it’s not their area of specialty).
But what concerns me more is when athletes get advice about supplements from the manufacturers themselves. Why? Because there’s a conflict of interest when the person selling you a product is also the one telling you what to use and how.
There are plenty of examples of sports food and supplement companies preaching to the public as the authority on sports science and nutrition. They don’t just provide information about their products, but give generalised nutrition advice to athletes with their products carefully incorporated. The information given can be a carefully selected sample of sports science, chosen to paint their products in the best possible light. The problem for consumers is knowing what they HAVEN’T told you. Often research showing theoretical benefits of ingredients doesn’t translate into actual performance gains.
A classic example is the marketing of magnesium for preventing cramps. So successful has this been that athletes commonly accept sweat magnesium losses as the cause of their cramps, gulping down copious amounts of magnesium tablets and sports drinks. However this is simply not supported by research. In fact almost all studies and review articles published in the last ten years show absolutely no relationship between sodium, potassium, magnesium or calcium and exercise-related cramping.
Even more concerning is when manufacturers promote the benefits of their products under the guise of a regular media article. One prominent outdoor/adventure sport magazine in Australia recently included nutrition articles as part of every issue. Sounds great, until you discover a sports food company is paying for exclusive rights to author them.
Why is this a problem? Well as an example one the articles included a glowing review on the benefits of D-ribose, an ingredient found almost exclusively in their products. But well designed research has failed to confirm the initial hype surrounding ribose, and I’m not aware of a single colleague who recommends it to clients.
Finally, there’s good science that’s been misinterpreted. In 2008 the University of Birmingham published the first study showing performance benefits of combining glucose and fructose in sports drinks during exercise. In this study cyclists drank 60 grams an hour of glucose and 30 of fructose (a 2:1 ratio). Several manufacturers latched onto this, reformulating and marketing their products and the 2:1 ratio as the key to unlocking endurance performance.
But the point of this study was that combining glucose and fructose is useful ONLY when you consume more than 60g an hour of total carbs. The same lab showed that the benefit is lost when consuming carbs at only 45g an hour. In other words it’s the total amount of glucose and fructose that’s important not the ratio, and this can be sourced from many combinations of products (even normal food).
As well as the sports foods there’s an ever-expanding array of pills, potions and powders claiming to boost performance or reduce body fat. However in Australia (and most other countries) dietary supplements are not regulated the same way as pharmaceuticals. Before it’s allowed into the marketplace drug companies have to prove not only that a medication is safe, but also that it works. Nutritional supplements only have to prove that they’re safe.
There was an excellent article on the sports supplement industry published in Sports Illustrated in 2009. They noted that “a drug company, like Pfizer or Merck, typically needs eight years to get a product from the lab to the consumer. In a mere two months, a VPX energy drink can go from…(concept) to machines that each churn out 230 bottles a minute—and then to store shelves.”
So where can cyclists get independent, up-to-date info on sports nutrition and supplements? For those on an sports institute scholarship you’ll have a dietitian at your disposal already. For the rest of us, look for an Accredited Sports Dietitian who specialises in endurance sports. The Sports Dietitians Australia website is a good place to start, where you can find one practicing in your area.
What sports supplements do you use and where do you get your nutrition and supplement advice from?
Alan is an Accredited Sports Dietitian who consults to several triathlon squads, the Tour de Cure cycling charity, writes for a trail running publication, and works in private practice. He’s lectured on nutrition for Cycling Australia’s Level 2 Coaching Course, and has worked with a variety of athletes from recreational to Olympians. He’s the founder of Next Level Nutrition, an online sports nutrition clinic where clients consult via the web, and occasionally finds the time to race his mountain bike.