How to fuel during an endurance race?

Welcome to the third installment in the nutrition for endurance athletes series! You should already know how to eat on the every day basis to fuel your training and how to prepare for the race ahead of time. Stage three: refueling during the race.

In which workouts/ races should I refuel?

Before you decide if you should plan on fueling during your run, you need to figure out if it’s long enough for that. For example, you can do a 5k without being weighed down by a bottle of water. How about a 10k? You’ll probably need water, but it still would be too early for eating while running. Cycling is probably even ‘worse’, since it’s not quite as intense as running. Your body can store up enough glycogen to fuel up between an hour and hour and a half of moderate effort race/ workout. So here is your first answer: if you’re planning to be on the road for over 90 minutes, plan on refueling.

When?

You’re tempted to say ‘I’ll just have some iso after an hour and a half’, aren’t you? That’s actually not the case though. Your body has limits to how much it can absorb at once, especially during running. It’s better while you’re cycling, which is part of the reason why triathletes focus on their refueling on the bike. I am pretty sure for like 99% of population saying ‘and it’s all downhill from here’ when you get to half or full marathon sounds ridiculous. I haven’t done a full ironman yet, so I can’t speak to that, but I definitely had that feeling when I was doing the 70.3. It may have helped that biking is my weakness, while I feel pretty confident at running. I was just grateful to be off the bike 😉.

Basic strategy is to consume your fuel every 10-15 minutes starting from the moment you start. You should be doing it as often as you can, but nobody can bike efficiently while sipping slowly though a straw in their aerobars 😜.

Start early, do it often.

During an Ironman, I sure will need to start my refueling immediately in T1! They say you have enough glycogen for no more than 90 minutes stored in your muscle. I will probably need about that much for the swim portion… Ugh! I will be starting from behind!

What? And HOW much?

So you’re supposed to consume your fuel pretty much continuously. But what is a good fuel for your endurance endeavors? Sugar. Carbs to be more accurate, but while you are working out, you want it as easy to absorb as possible, so basically sugar in liquid form (combined with electrolytes – but I already talked about that in the hydration post). If you’re planning on being done within 150 minutes, 30-60 grams of carbs per hour should suffice. If you’re going for longer than that, you’re going to need 60-70 grams per hour. As long as you can stomach it, try for 90 grams per hour for those really long distances – this may be easier done on a bike, when your metabolism is not cranked up as high as during a run.

So: carbs in form of sugar.

In what form?

This is definitely a hard question, especially since it involves personal preferences.

Sport drinks

Your first line of defense consists of sports drinks. You can buy them at any grocery or convenience store out there. They are ok, but I find their taste too intense when I’m on a long ride and need both water and sugar. A huge advantage of buying specialized powders to mix your own drinks? They are easy to pack and travel with. I also tend to mess with concentration (since sometimes I want to taste them, while sometimes – not even a bit). My biggest issue with sport drinks: they work for like a marathon, but during longer rides and races, I want something to bite into. I have always found food in liquid form to be deeply unsatisfying.

Gels

I feel like these are an acquired taste… I find that they engage my gag reflex. On the other hand, they are easy to carry and light. You buy them in small packs, so it’s easy to tell the amount you are consuming. My personal preference to the side, you will need to wash them down with water, but that’s easier to find during a long workout or in a race.

Chews

I think I need to try these for runs! I usually just go with gummy bears 😅. Easy to store, carry and dose. But you will need water to wash them down.

Real food

What you consider real food is debatable, but after spending all day on a bike, I can definitely vouch for wanting to eat something that looks like a meal I may have while not working out. Obviously, some are better, like bananas and fruit pouches than others like donuts. Don’t laugh… This is was a rookie mistake and a hard lesson during my first marathon. They were giving away free donut holes. So I grabbed one and shoved it in my mouth. I ended up over a trash can trying to spit it out because I didn’t have enough saliva to even chew it effectively. I won’t be doing that again…

I hope you are now all ready for your next long run, ride or are planning your nutrition for that next big race. I will see you out there!

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