Race Day Nutrition
During college in the mid 80's I fancied myself to be quite a pool shark, until one night I got spanked by an old guy. I asked him how he gotten so good, he said, "Son, if you waste enough time doing something and learning about it, you can get good at it, in spite of a lack of talent or intelligence." Lesson learned. After the nutritional mistakes of my first Ironman, I set myself to learning everything I could about race day nutrition. The following is a summary of some good, commonsense race day nutrition info and my nutrition plan for IM California. As with anything else, don't take my word for it. Read the references included below and try this stuff out in training before your race.
The amount of energy that your body uses to "go" is measured in calories. Pretty simple. The faster you "go" the more calories your body must burn. Based upon your weight, effort, economy, etc, you will burn between 600-1200 cals per hour. Your body has two primary sources for this energy: fat and carbohydrate. At about 3500 calories per pound, even the thinnest triathlete has more than enough fat to carry him through a 12-16 hour Ironman.
Unfortunately, your body must burn carbohydrate in order to burn fat. "Fat burns in the fire of carbohydrate." Your body's primary sources for carbs are glycogen stored in the muscles and liver (about 2000 cals), and food ingested during exercise.
During low intensity exercise, say 600 cals per hour, your body gets most of its energy from fat. So let's say that of this 600 cals, 450 is from fat and 150 is from carbohydrate. However as intensity increases, the percentage of fat burned remains relatively constant, and the difference is made up by carbohydrate. For example, as intensity increases, you are now burning 900-1000 cals per hour. Only about 500 will be in the form of fat, the remaining 500 will be carbohydrate.
Another thing happens as intensity increases: you are less able to digest the food that you are eating. Sitting on the couch reading this, you could probably polish off 6 donuts, no problem. Try eating those same donuts during a 40k TT and you will probably experience severe cramps, bloating, and other fun stuff. Your body is too busy making you "go" to digest those donuts.
Effects of Racing
If you do the math, you can see that if you don't eat, it is not too long before you run out of carbohydrate, which again is needed to burn fat. When this happens, you "bonk." Essentially your body must change gears and use a different energy source to burn fat, in this case muscle. Your body is unable to use the V-8 under the hood and must pull-start the lawnmower engine in the trunk. Perceived exertion increases and speed decreases. Dizziness, lethargy, confusion, etc are other symptoms of bonking.
A byproduct of the energy burning process is lactic acid. The intensity level at which your body is removing lactic acid as fast as it is produced is called your Lactate Threshold Heart Rate (LTHR). As intensity increases above this level, lactic acid is not removed from the muscles faster than it is produced. Lactic acid builds up and will eventually force a decrease in intensity. You will slow down or be unable to continue. During Ironman racing, you will be well below your LTHR. But after hours and hours of effort, lactic acid still has plenty of time to do its thing to your muscles.
Your body must also cool itself by sweating, resulting in a loss of sodium. If this salt is not replaced, either through sports drinks or salt tabs, a state of hyponatremia will result, causing severe muscles cramps and in extreme cases, death.
Let's review: As intensity and length of exercise increases, the following things will occur:
1. Your body burns more calories.
2. More of these calories come from carbs than from fat.
3. If these carbs are not replaced, you will bonk.
4. Your body's ability to digest food decreases as intensity increases.
5. Lactic acid is circulated through your muscles, causing fatigue, muscle cramps, etc.
6. Sodium and water are lost through sweat and must be replaced.
Race Day Success
A successful race day plan will have the following elements:
1. A pace, most commonly defined by a heart rate range, that:
· Is fast, but just slow enough to minimize or prevent the build up of lactic acid in the muscles.
· Allows your body to process the necessary numbers of calories to replace carbs burned during exercise.
2. Starts the race with a full tank of gas: well-stocked glycogen reserves.
3. Encourages your body to burn fat and conserve glycogen.
4. Replaces sodium and water lost through sweating.
Developing your plan starts months before your race, when you determine the correct race pace. During your long training rides/runs, experiment with your pacing and find a heart rate range that feels comfortable and at which you can eat and digest an adequate amount of food. Through my training I've determined I can sustain a heart rate of 147-152 for hours. I've also determined that at this heart rate I can process 300-350 calories and 1.5-2 bottles of fluid per hour. This pace and absorption rate are the foundation for my race day nutrition plan.
Rich's Bag o' Tricks
1. During your training, do short rides and runs (less than 2 hours) on an empty stomach. Assuming you have 2000 calories stored as glycogen, you should enough to sustain you through 2-2.5 hours of high intensity exercise. By training on an empty stomach, you train your body to conserve glycogen and burn more fat, since it eventually learns that you ain't gonna feed it. Do your long stuff on a full stomach, especially long runs. By training with a full stomach, you get used to the feeling of riding/running with a lot of stuff in your gut. You will also learn how to deal with mild cramps and side stitches. [I would point out the importance of replenishing the glycogen stores shortly after working out. By working out on an empty stomach for shorter distances you are, in a way, carbo-loading daily and keeping the glycogen stores optimal for your longer workouts. This is because the glycogen is depleted to a level where you are ready to bonk and when exercise ceases the enzyme (glycogen synthetase) necessary to store glycogen is revved up resulting in supranormal glycogen levels in the muscle. This enzyme level drops off after about four hours, so it's important to eat during that time window. As an aside (and a not very important one since fructose is in so many drinks and bars) is that a small amount of fructose post exercise aids in topping off liver glycogen levels. - Jeff Roberts, M.D.]
2. Carbo-loading and large race day breakfast. Starting 3-4 days out, I begin eating lots of carbohydrate, in the form of pasta, potatoes, and non-fat frozen yogurt J. I also wake up at about 4:00am on race day and have a large liquid breakfast, 700-1000 calories.
3. Caffeine has been shown to help your body burn fat and conserve glycogen. I have a cup of coffee before every morning workout and used Vivarin on race day.
4. MCT (Medium Chain Triglyceride) is a form of fat that is not stored by the body. Instead it is immediately used as soon as it enters the bloodstream. Trained endurance cyclists have been shown to increase performance by 6-10% when drinking an MCT/sportsdrink mix. I used Metabolol Endurance mixed with Gatorade. After the race, one of the coaches at www.trainingbible.com recommended mixing with Cytomax rather than Gatorade. Cytomax is glucose-based, while Gatorade is fructose-based. I have not tried this mix.
5. Loading with sodium phosphate (PhosFuel). Sodium phosphate acts as an acid buffer, reduces the build up of lactic acid, and thus increases the body's tolerance for lactic acid. [It also enhances offloading of oxygen from hemoglobin to muscle tissue. - Jeff Roberts]
6. Pre-race sodium loading and salt tabs on race day.
Pre-race and Race Day Nutrition Plan (for a Saturday Ironman)
My personal parameters: my race weight is about 163 and I can digest 300-350 cals per hour at a heart rate of 147-152. I am a heavy coffee drinker and years of swimming mean that I can swim very comfortably with a full stomach. You may be different. I highly recommend that you try this entire routine before a long race or long training weekend.
Tuesday: Stop drinking caffeinated beverages. If you are a heavy caffeine drinker, this will allow caffeine ingested on race day to have more of an effect. I did have a bad headache for 1-2 days due to caffeine withdrawal. Begin carbo and PhosFuel loading. Eat lots of pasta, breads, potatoes, etc and begin to take 4 PhosFuel tabs a day. You will also be tapering at this time. The reduction in training volume insures that you are well rested on race day, and that carbohydrates are converted to glycogen and stored in the muscles, not burned through exercise during race week. Since one molecule of glycogen is stored with four molecules of water, you may see a weight gain of 3-5 pounds by race day. You may also experience some muscle stiffness and aching, as your muscles become packed with glycogen. Try to think of the extra weight as a full tank of gas that you will need to get you through a very long day.
Wednesday: Continue carbo/PhosFuel loading, begin hydrating with a sports drink, and lightly salting food. The sports drink will help you carbo and sodium load, as will salting your food.
Thursday: Same as Wednesday.
Friday: Continue carbo/PhosFuel loading, hydrating with a sports drink. Take 2-3 salt tabs throughout the day. Have a very large pasta lunch. Early, light dinner and two cans of Boost or Ensure before bed. Idea here is to eat a lot of calories, but to have a clean digestive tract for race day.
Saturday:
0400, breakfast: 16 oz of Naked Juice Protein, 2 scoops Metabolol Endurance, top with OJ, about 800 calories. 1 cup of coffee.
0600: 800 mg Vivarin, 800 mg Advil, sip water bottle until 0650.
0700: Race start. When I tried this plan in training, I was a little hungry when I started. My stomach had digested the liquid breakfast and I knew that I controlled whatever went into it from that point. However, on race day I was still a little full for the start, due to pre-race nerves. Expect this.
0800: On bike: 3 bottles w/ 2 scoops Meta, 1 scoop Gatorade (300 cal each bottle), salt tabs. Idea of sodium loading for days prior was to eliminate need for salt tabs on race day. Still carried them just in case.
Bike & T2
Lap 1:
Set watch to beep every 10 minutes, sip 4-6 oz of feed bottle, sip water. Goal is one feed bottle and .5-1 water bottle per hour. Take a gel every hour with 6-8 oz water if you feel like the plan is working so far, but be sure to let your body settle into cycling mode. Throughout race day, think of water as an aid to digestion. If you eat something calorie dense, such as a gel or bar, be sure to sip 6-8 ounces of water with it. This will keep you hydrated and ensure that your stomach can digest your food. I did not use an aero bottle. I don't think it's very aero to have this thing stuck out in the wind, especially if you only use it every 10 minutes or so. For the other 9:50, I think it creates drag. My routine was to grab a bottle of water at the aid station, immediately drink 10-12 ounces, use the rest to cool myself or just rinse out my mouth. Toss the bottle near the end of the aid station.
Bike Special Needs:
3 feed bottles, film canister with 1 Vivarin, 1 salt tab, 2 Advil. Take tabs and drink water. Continue with feed plan.
T2:
1 feed bottle, film canister with 1 Vivarin, 1 salt tab, 4 Advil. Take tabs with water, sip feed bottle for first 30-45 min, then Gatorade at the aid stations. Gel every hour with cup of water.
Run Special Needs
Dry socks, film canister with 1 Vivarin, 1 salt tab, 2 Advil. I ran right by the bag, didn't even see the special needs station.
The run is where you have to use your head. When I took that feed bottle out of my T2 bag, I immediately wanted to toss it. I just didn't want to drink the same thing any more. I ditched it at the first aid station. Any problems with over/under eating, hydration, low sodium, will likely manifest themselves on the run. Use these principles:
1. Try to stick with your pre-determined cal/hr at your pre-determined target heart rate. If you are above that target heart rate, assume that you will have to eat less. I didn't do this and ran into a little trouble at mile 9. I tried to run with Harry Friedman for about 5 miles and my heart rate was 6-10 bpm above my target. My stomach was not processing my fluids and I was a little bloated by mile 9.
2. Drink mostly Gatorade: calories, water, sodium.
3. DRINK WATER WHEN YOU EAT SOMETHING.
4. If you start to have problems, slow down or start to walk through the aid stations. If that doesn't work, stop for a couple of minutes. Your heart rate will decrease and allow your body to solve whatever problem you have.
5. Consider walking through the aid stations. At mile 9 I was forced to walk through the aid stations so my stomach could do its thing. I immediately noticed that I felt much better during my run between aid stations and was able to run faster. Come up to an aid station and begin to get what you need, continue walking, watch your HR and let it get 15-20 bpm below your target. This allows "everything to reset" and ensures that you are letting your stomach do its thing. Then start running at a good pace. What I found was that I was able to run a faster pace and just when my HR began to get out of my target range (150-154 for the run), it was time to hit another aid station. Like doing mile repeats with a buffet table set up after each mile. For the last 6 miles, I doubt that running too fast will be a problem for you. Yeehaw.
Like anything else, "try it before you buy it." Whatever feed plan you determine for your race, be sure to rehearse it at your expected race pace.
References:
"Triathlete's Training Bible," by Joe Friel, Chapter 16
"Endurance Sports Nutrition," by Susanne Eberle
"The Mathematics of Race Fueling, by Dan Empfield, slowtwitch.com/mainheadings/coachcorn/racefuel.html
Rich StraussRich is a Joe Friel Ultrafit Associate, an Ironman World Championship Finisher, a USAT certified coach, and the founder of the Pasadena Triathlon Club in Pasadena, CA. Rich has personally trained over 250 Ironman finishers since 2001, and helped thousands more coach themselves more effectively through his training articles and active discussion forum. His endurance training company, Crucible Fitness, offers a range of personalized coaching and performance services, including FIST certified bike fitting and metabolic analysis with the NewLeaf system. He also sells affordable half and full Iron distance training plans through TrainingPeaks. Visit www.cruciblefitness.com for a complete list of services.






