06 October, 2009

Eating For Racing or Big Days

    Ever had a massive bonk on your tour, or even during a race? Most of the time, that bonk comes from what you have had to eat, and the other percentile is when you’ve out stepped your limits. So what should we eat before, during, and after to make the most of the day? It boils down to how much, and the quality, and kinds of food you want to eat.
    I began researching performance eating a few years ago, after having a few eye opening bonks, and trying to push my touring experience. I found it to be one of the most interesting things to learn about, and now know how complex it can be, especially when coming to understanding blood sugar, insulin response, and gastric emptying. But when it comes down to it, its fairly simple, eat simple foods, don’t over indulge, try to stay away from sugar and greasy foods, and hydrate.

Before Going Out

  • Breakfast
    Breakfast is really important when putting a big day in, however, when racing one must be incredibly careful with the timing. When you are racing, ensure you have 3 hours to digest before racing, as the gastric emptying of your stomach (1 liter per hour) will not be fast enough if you eat to soon to the race. The idea with breakfast is to top of liver glycogen stores. For a big ski tour, I like a big bowl of oatmeal, with ground flax, rice milk, cinnamon, hemp seeds or pecans. The oatmeal is a complex carbohydrate giving me energy, as well as the rice milk, the ground flax is a good quality fat, and the hemp seeds or pecans are a protein, which will help stabilize my blood sugar levels. The idea is that this breakfast will give me a slow release of glucose into my blood stream throughout the morning. Having a sugary breakfast like a muffin, maple syrup, or whatever can cause a spike in glucose levels as it is released rapidly, and causes a strong insulin response. This will cause you to bonk later in the day.
  • 15 minutes before exercise:
    • 300-500ml of water (not Gatorade or electrolyte drink),
    • 100 calories of easily digestible fuel (the same fuel you plan on using during the day).
During The Day/Race
  • Liquid intake rate should be 150-250ml (5-8oz) every 15 minutes.
    • There is 5% decrease in performance for every lb lost during exercise. The down side of drinking water, we are limited. Drinking too much can cause hyponatremia (over hydration) and stomach bloating/cramping. Drink water but not too much.

  • 100-300 calories per hour.
    • 260-280 calories per hour is optimal. By ingesting small amounts, under 300 calories, it allows the body to continue using the most energy on the task at hand (skiing) and not diverting energy to digesting your food. Taking in more than 300 calories can also cause stomach upset, every notice after a long big lunch out that you are sluggish and can’t push the pace?
    The food should be very easily digestible, and when I say easy, I mean really easy. Foods that are easily assimilated into the stomachs walls are incredibly important; otherwise you may be burning more calories to digest it than what it gives. Foods with lots of sugars in them, raise your blood sugar levels too high causing a strong insulin response, and affect the osmality of the stomachs walls (thus not taking in the food you have given your body as easily, and creating bloating and/or cramping).
    So what to eat? Liquid diet foods such as gels, chews, sports drinks, and foods like dates, are easily digestible, and will allow glucose levels in the blood to be more stabilized. Eating solid food is important for long endurance efforts, such as big days, training, and speed traverses. Eating some solid food is important for the body, and mind, and gives the body other forms of food rather than just carbohydrate. Ingesting good quality fats and proteins are important. Fat burns as an energy incredibly well, keeps you warm, and will make sure you go long. Fat is your primary endurance fuel, so take in good quality fats, bad fats won’t help. So put down that greasy bacon breakfast, it’s not helping. Protein helps rebuild muscle tissue and can have important amino acids in it. I recommend a ziplock bag of almonds to munch on during the day. The protein and amino acids in them will help prevent muscle cannibalization, and help aid a faster recovery.

After Your Done
Within 45 minutes of finishing
  • Drink: 600-720ml of water for each pound lost
  • Eat: approx 60g of high quality carbohydrate, and 10-15g protein, with a small amount of good quality fat.
    • This stage is essential for a good recovery, and be able to get out the next day, even if your just taking it easy. Eating these amounts right away, as a snack, will help rebuild your glycogen stores you’ve depleted over the day, and begin repairing your muscles. A good dinner an hour later or so, after you’ve gotten home and relaxed, will help continue that process.


  1. "260-280 calories per hour is optimal. By ingesting small amounts, under 300 calories, it allows the body to continue using the most energy on the task at hand (skiing) and not diverting energy to digesting your food."
    -- That seems kind of on the high side compared to other estimates I've seen, which are also keyed to body weight. And any thoughts on whether this should be adjusted downward for relatively short races? (Here in New England, the very longest races aren't much over two hours, and some are closer to just an hour.)

  2. Setting up to what works best for your body is by far the best measure. The problem which most people will have with their gel is simple sugar. For the full 260-280 calories, the product must only have no more than 6-8% mixture of simple sugar, as it will disrupt the stomach osmality and not allow it to be taken into the blood stream as efficiently.

    The argument that does get thrown around with less than this amount, is that it may take a certain amount of calories to simply digest and covert your fuel, into glucose.

    For races that are an hour, maybe 1 100 calorie gel, is enough. For 2 hour races, 2-4 100 calorie gels, is suitable. You are best to experiment and note that if you are using a hydration tablet or powder, you may already be ingesting calories. Use caution on any that have simple sugars in them. Just important to not exceed 280-300 calories per hour.

    This info was derived from a Nutritionist, Steve Born, and personal testing. Do what works best as usual.

  3. This all great info, similar to much i have been reading up on. My only question is if you have ever used a blood glucose meter to test your blood sugar after eating oatmeal for breakfast? For some people oatmeal does raise blood sugar significantly along with the subsequent insulin response.


  4. Hey Kyle,

    Great question! I haven't used a blood glucose meter. But oatmeal (cooked oats) is a middle of the range Glycemic Index (55), so it does not have a huge insulin response. I do add ground flax seed to help balance and reduce the insulin response. The ground flax is an anti-inflammatory which is important, as your body is in constant inflammation while training and racing. I would also recommend nuts and seeds with it, as these stabilize the blood sugar levels as well, and add a bit of protein to the meal. Everyone will react differently to everything so testing is important.

    I have been using Oatmeal as a key breakfast for big days for years, and have 'engineered' what works best for me. It also helps dating a nutritionist who watches over everything I eat as well. Hope that helps!

  5. Cool,

    Being an athlete you are also in tune with and know how your body responds. Oatmeal can be a tricky one, I have diabetic relatives and some can eat it and for others It can super spike their glucose levels, even when the general consensus says it shouldn't. For me it's kinda borderline, I had never heard about the anti-inflammatory properties of flax though, that's good to know.


  6. Great feedback Kyle! I'm always stoked on trying to find a more efficient fuel for the day. Just a note flax must be ground, otherwise the benefits aren't accessed by the body, as it isn't digested and absorbed the same way. I do use organic steel cut oats, not a packaged mixture, so their is no sugar. The sweetness for me comes from either blueberries or banana, whichever I feel like for the morning. There are some great fueling options available if you look up the Thrive Diet, which are designed for endurance, and work well. Otherwise keep testing!

  7. Awesome post! So much good info...

    BTW, Kyle, if you find that oatmeal is spiking glucose levels, barley is an excellent option. It's the lowest glycemic index grain. You can cook either the whole grain or flakes--like oatmeal. Sadly the cook time is over an hour for the whole grain. My fiance likes to cook up a large batch at the beginning of the week and then we just keep it in the fridge and reheat it with fruit, nuts, coconut oil... etc. through the week.