Posted in Run and tagged nutrition, performance

by Zoe Wilson

I was having a race debrief with a friend of mine who competed in the Forster Long Course over the weekend. He was running me through his race - he felt good in the swim and came out feeling strong but had a disaster on the bike. He’d dropped his nutrition and had nothing but a bottle of sports drink and a bottle of water to get him through the 90km.

We all know the feeling of hitting the wall - that moment when you begin to feel like you’re running slow-motion through a pool of wet cement. The cause? Not enough fuel for your body to use when you’re putting it through it’s paces.

Nutrition and Performance

“So, why does nutrition play a part?”, I hear you ask. It’s pretty simple really: your body utilises the sugar (or glucose, from carbohydrates) in your blood to feed your muscles when they’re working. The harder and longer the muscles are working, the more glucose they need. If there’s not enough glucose floating around in your bloodstream, your body has to convert fat and protein to use for fuel instead. Using protein and fat is not as efficient as using glucose and when demand outstrips supply you come to a grinding halt. Just like a car when you’ve ignored the petrol light for too long.

Avoiding the wall

The best solution? Eat or drink some quickly digested carbohydrates (i.e sugar) during your session to boost your blood sugar supply. The general aim to take on board 30-60g of carbohydrate per hour, beginning  the refuelling process around 30 minutes from the start gun. Sports drinks, gels, lollies, sports bars or fruit are all great options but for shorter races like sprint or olympic distance triathlons. Sports drinks and gels are often the most convenient (long course and Ironman is a different kettle of fish and I’ll talk about this in one of my upcoming posts). With sports drinks, you’re address both hydration and fuel in one go, which is why there are often a great choice. Most importantly, whatever plan you decide on, make sure you practice in training too so you don’t end up in the Porta-loo when you should be out on course.

And my friend who lost his nutrition? He managed to get by with his bottle of sports drink on the bike and caught up by hammering his nutrition in transition and on the run. It wasn’t a PB but there wasn’t a wall in sight. 


Zoe is a triathlon-mad Accredited Practising Dietitian with a keen interest in sports nutrition. Most of all, she loves making nutrition concepts easy for any old person to follow. Find her at