Wednesday, February 27, 2013

Fueling for 50km (skiing, that is!)

What do you eat?

It's probably one of the most-asked questions an endurance athlete gets. Whether it pertains to daily diet, how to stay lean, or how to fuel for training and events, people are quite consumed (so to speak) with what skiers and runners put in the tummy. And in truth they're worthwhile questions; lost is the athlete who doesn't eat well. For training, it can derail decent workouts into bonked disasters and poor recovery; for races, well...if you have never experienced the giant's hand come crashing down upon your skull, reducing you to a whimpering wet blanket who lusts only that enormous, pan-fried-in-butter Angus burger with blue cheese and caramelized onions... Ahem. Excuse me, I appear to be hitting the wall. Allow me to snarffle a gel, post-haste.

Ultrarunners who compete in 50 and 100-mile events have their own personal mixture of voodoo and peanut butter to fuel them through the grueling day, but skiers must rely on different means. Lacking the ability to carry hand-held bottles, or effectively use running packs such as those from Ultraspire, skiers must instead look to more compact fuels and sparse intake methods.

Last week I competed in the American Birkebeiner 50km ski marathon in Hayward, Wisconsin. I'm a sprinter by ability, so my foray into the ski marathon realm was a bit of an experiment. While I've spent plenty of long hours in overdistance workouts in the training months, it's rare that I spend more than 30 or 45 minutes in a ski race. So going into this race, I wanted to make sure I was prepared, food-wise. As a bigger athlete, I know I'm burning a lot of calories and while you can never replace calories lost in a 1:1 fashion during hard training or races, you must maintain some level of replenishment so your body doesn't enter a state of catabolism (scavenging muscle tissue) or just simply shutting down (i.e. cramping, bonking, general unpleasantness).

Check out the "Jingle-Gels" attached to the drink belt.
My plan for the race was simple: I had one 24oz bottle of strong HEED, and one gel per every half hour of racing. Also, I had a smaller bottle ready to be given to me by a friend at the 38km mark in the course. This was my "Go Juice" bottle, filled with flat Coke and a few crushed-up caffeine pills. This is an old marathoner's trick: your body, at the tail end of a long 2+ hour effort, is craving sugar in any form. Combine simple sugars such as those in soda with a jolt of caffeine (which not only serves as a stimulant but also helps to mobilize fat tissue for metabolism), and you've got a ready friend in your time of need. I should mention though, along with all fueling during races, please experiment with different drinks and foods during training before using them in races. The options I'm suggesting here might not work for you in the same way as me, either in terms of quantity or type of fuel.

Perhaps the most important thing to remember in fueling for anything, be it training or a race, is to be consuming calories BEFORE you start feeling the craving. Tim Noakes has a compelling new book which argues that we need far less liquids than we typically consume during race efforts. And yet, hydration aside, sports drinks offer a ready source of calories in an easy-to consume medium. I've read that your muscles can store up to 2500 calories in glycogen, which is ample for a two hour competition. However, completely draining your muscle glycogen stores to the bottom of the tank can't introduce good vibes. I'd rather end a race with a bit left in the tank, and save myself the bonk/cramp/crankiness.

Bottom line: for ski efforts lasting two to four hours, plan on 200-250 calories/hour of fueling. One Hammer Gel contains 90 calories, and a two-scoop bottle of HEED has around 200 calories, so consider taking a gel every half hour, and a few big swigs of HEED every fifteen minutes. I find that if I schedule it in this manner I remember to actually feed. Another way to do it is by kilometer; many ski marathon courses have kilometer signs, which allow you to break the course into sections. For the Birkie, I ate a gel every 10km, and took a few big slugs of HEED every 5km. Play around with these strategies and experiment with different foods and drinks. You'll find a sweet spot of fueling that helps you maintain a steady level of energy without introducing a heavy stomach or discomfort.


  1. Just skied my first Birkie and found myself looking for a cheeseburger station at about 40K. Curious what you recommend for pre-race fueling?

  2. Hi John;

    The Mosquito Brook aid station (km 38) in the Birkie is where I got my "go juice" feed - definitely the spot in the race where cravings go wild!

    Good question on pre-race fuels. Because of the relative high-intensity of skiing it's important to not have a big load of simple carbohydrates close to a race start. In other words, the huge pile of pancakes and syrup won't be good. I go with a bowl of oatmeal (rolled or steel-cut are less processed, therefore better for you, and longer-lasting metabolically), with some fresh fruit and nuts. The oatmeal is carbohydrates but they will take longer to metabolize, and the nuts have a good supply of fat. It will leave you satiated without inducing an insulin spike. Some folks have yogurt or milk as well; provided it doesn't upset your stomach they are good sources of fat and calories, too.

    Most important in my opinion is timing: make sure to eat your pre-race meal around two hours before race start. That will allow for digestion before you begin your warm-up. Be drinking water too, especially if you're like me and drink a hearty amount of coffee on race mornings. The water will help balance out the digestion and help replace the fluid loss which will occur due to the diuretic effect of the caffeine.

    Some folks like to eat something right before the start, such as a gel or bar. I don't think it necessarily helps in a metabolic manner, but if it makes you feel better or takes the edge off, it's OK. At that point you've warmed up and are ready, so your metabolism is higher and the sugars in the gel will get burned and not induce a spike.

    Hope this helps!