Nutrition in an ultramarathon is a tough subject because it is very individual and any mistake can cause severe drawbacks in performance. That said, there are some good guidelines to use a starting point. This post is just a starting point and I will test and modify as the summer goes along.
I weight about 188 pounds and estimates suggest that I burn about 140 calories per mile (at high intensities). If I manage to finish Leadville Trail 100 in 25 hours, that would be approximately 4 miles per hour. Assuming an equal level of effort throughout the race, that would be 560 calories an hour. Given the slower nature of ultras, I will burn fewer calories and will probably be in great shape if I can consume 400 calories an hour. At ultra marathon speeds/efforts, it is estimated that a well-trained athlete gets about 50% of their calories from carbohydrates (200 per hour). So there you have it, I need at least 12,000 calories to complete this race without a deficit. Chances are I will have a small deficit, but hopefully it is less than 100 calories per hour. That means the bare minimum I need to consume is somewhere around 10,000 calories to perform at a high level.
Somethings don't change from shorter races (those less than 4 hours in length). A runner will continue to get significant portions of calories from beverages (a sports drink). Hydration and electrolyte balance remains the primary concern. But other things change significantly. At slower speeds, Hyponatremia (too much fluid and too little electrolytes) becomes a bigger risk. And the need to consume protein and fat becomes much more important. The recommended percentage of calories is something close to the following: 65% carbs (260 cals, 65 grams), 25% fat (100 cals, 25 grams), and 15% protein (60 cals, 15 grams). Those percentages look familiar. Below is the reasoning for using the other "macro-nutrients":
- Prevent central nervous system fatigue
- Prevent cramping
- Prevent muscle wasting ("cannibalizing")
- Ensure effective processing/usage of glycogen
- Satiate hunger
- Satiate hunger
- Ease the gut
- Gel shots are not the best source of carbohydrates because they are concentrated and draw fluid away from the gut to properly process them (can leave you dehydrated). It is estimated that you need to drink 6 to 8 ounces of water with every Gel shot. Seeing as how you can only process 24 - 30 ounces of fluid an hour, you don't want to waste too many of those diluting gel shots.
- A minimum of 500 mg of Sodium per hour to replace sweat, particularly in hot conditions. 1000 mg is the upper limit. My plan is to use S-caps. Probably zero early, 1 an hour when the sun comes up and maybe 2 per hours when the sun is at the highest point. Something like that.
- A banana every 3 to 5 hours will help to maintain electrolyte status (potassium and magnesium)
- Drinks with maltodextrin or glucose (instead of fructose) are easier on the stomach
- Caffeine is recommended, but intake of more than 200 mg can result in caffeine intoxication. I will probably leave most of my caffeine consumption for the night time.
- Of course, as the weather gets warmer it will be harder to eat as blood and fluid are drawn away from the stomach to support the cooling of skin. The only real option here is slow down some. Hopefully much of this is already built into my pacing plan.
- There are all sorts of other supplements/drugs to consider, but the primary ones are sodium, candied ginger (for an upset tummy), NSAID, and Imodium.
250 calories per hour from a maltodextrin based electrolyte beverage. I am currently experimenting with GU Roctane beverage. It is 240 calories per 2 scoops and mixes well with 21 ounces of water. In hot conditions, I might be able to take this up to 30 ounces and 300 calories per hour. Another drink I will consider is Accelerade because it has the recommended 4:1 carb to protein ratio. A late entry into the electrolyte beverage contest is Clip 2. Clip 2 is a little different because it possess a better balance of nutrients than either Accelerate or Roctane. It is not as high in sodium, but it is made by the makers of S!Caps, so I am sure they are meant to supplement one another. Some pretty good ultrarunners swear that it yields superior results (low GI distress, reduced muscle soreness, reduced fatigue) in runs over 30 miles.
|Drink||Calories/Bottle||Carb g||Fat g||Protein g|
Solid foodsSolid foods are a much tougher subject and lots of experimentation is needed. Below are some of the foods that I have found I can tolerate and am considering for the race. To get the proper nutritional values I desire, I may have to make some home made recipes that combine these ingredients.
I have a little bit of experience here that will help me. First, I ran my first ultramarathon last year on nothing but fluids, some fruit, and sugar (gels and chews). While I had a decent race, my stomach was a mess and prevented me from finishing hard on the final 10 miles of downhill. In subsequent long runs, I have had very good success mixing in protein bars (Big 100) and Bonk Breaker bars to give my stomach additional nutrients beyond sugar. I will certainly experiment with a continuation of those products and possibly create some of my own bars based on my nutritional standards.
|Food||Calories/Serv||Carb g||Fat g||Protein g|
|Bonk Breaker Bars||250||35||9||8|
|Cyto Sport Whey Protein||140||3||2||27|
|Pinole (Corn Flour)||440||88||4||8|
If you look at the data, you can see why the rage (based on Born to Run) would be toward eating some type of concoction that includes Corn Flour and Chia Seeds. A really good recipe that I have been experimenting with was posted on TrailAndUltrarunning.com.