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Fueling Your "A" Race

Dana Eshelman, MS, RDN, CSSD, METS I

Race day nutrition is something you want as a tried and true practice for YOU. What you consume the days leading into your race, foods and beverages you have on race day morning, what you have during your race, and what you like to have for recovery nutrition are all practices you can simulate on your big training days.

We are going to dive into how you know if your current plan is working, feeding and hydration strategies for before, during, and after races, and why you want to imitate this plan before race day.

Pre Race Nutrition

Eating a quick snack and running out the door may work to hit a training session, but for a race your nutrition plan starts 24 to 72 hours before the race start. Research shows carbohydrate loading postpones fatigue and is able to increase stamina for steady state activity by ~20% as well as improve performance by 2-3%; it is most effective for races lasting more than 90 minutes (look out for a future post on how to and when to carb load). If you are new to racing or have not carb loaded in the past, it is best to start small. The 24 to 72 hours pre race, your main focus is on:

  • high carb -- aim for half of your plate at each meal containing carbohydrate/ starch-rich food choices

  • lower fiber to minimize GI distress. This is highly individualized.

  • lower fat -- choose lean protein choices, minimize heavy or cream based sauces/ dressing, avoid cooking with oils or butter

  • minimize spicy or fried foods

  • stay on top of your hydration by aiming for urine a light lemonade color

On race day keep it simple! Follow guidelines above for high carb, low fat and low fiber. Plan to eat breakfast 2-3 hours before your race start with around 2-3 grams carbs per kilogram body weight (to get kilograms, divided your weight in pounds by 2.2). Along with your breakfast, have 12 to 16 ounces of electrolytes (these can also be a part of your carb intake). This may look something like 1/2 c oatmeal + banana + 1 T honey + nut butter (80 grams carbs, 10 g protein) with 12 to 16 ounces of skratch clear (13 g carbs, 380 mg sodium). You may sip on your electrolytes through the morning before your race and plan to finish them about 1 hour before.

In that final hour before race start, aim for some simple carbs at 0.5 to 1 g carb/ kilogram body weight. This can be energy chews, a gel, graham crackers, or 1/2 a pb and honey sammie, to name a few. You may drink to thirst in this last hour.

Big picture, in the 48 to 72 hours before your race day make your nutrition and hydration a priority and stick to what your body knows and loves. The local cuisine and drinks can wait until post race!

Getting Adequate Total Calories

Calories are the bodies currency of energy. Your body is able to store 1,800 to 2,000 calories in the form of glycogen in your muscle and liver that can be utilized as energy for up to 90 to 120 minutes. Once you have exhausted these stores, your body begins to utilize fat and muscle for energy production. However, energy conversion from fat is a very slow process and will lead you to "hit the wall" or "bonk". The muscles PREFERRED source of fuel is carbohydrate (especially at higher intensity), so let's give the body what it is asking for!

A great starting point is 200 to 300 calories (50 to 75 grams carbs) per hour for sessions over 90 minutes. If you are not currently fueling, you will want to consider starting small, around 100 to 150 calories (30 to 40 grams of carbs) per hour, and training your gut to tolerate more carbohydrate. Research supports consuming up to 90 grams of multiple sources of carbs (ie. glucose, fructose, galactose, maltodextrin, cluster dextrin) per hour for endurance athletes competing longer than 2.5 hours. Consuming a variety of carb sources increases the rate at which your gut can utilize these carbs which means less incidence for gastrointestinal (GI) distress - gas, bloating, stomach cramping and diarrhea. You can find these carbs most commonly in your sports nutrition products such as sports drinks and powders, energy chews, gels, and gus.

Now lets get into when to consume these carbs. I am sure you have heard, "fuel early and fuel often." This is exactly what you are aiming for on race day. In combination with pre race nutrition, consuming carbohydrates early and often prevents you from hitting a wall later in the race. That means fueling even when you do not feel like you need it. If you wait to take in your nutrition when you feel like you need it, it is too late. Now, we are working at digging you out of a hole versus performing optimally. A good place to start is having 20-30 grams of carbs every 30 minutes. If you are using a nutrition product such as a standard gu or gel that is concentrated, be sure to take this with at least 2-3 gulps of water to help with absorption and limit GI issues.

If you are in the zone racing and miss one of your 30 minute blocks of feeding, this does not mean play catch up. Consuming too much at one time can be hard on your stomach! Instead, take it when you remember and adjust your nutrition to follow.

Don't Forget to Hydrate

Hydration is dependent on sweat rate, climate (hot, dry, humid, cold), and altitude. Without making this too complicated, you can start with sixteen to twenty ounces per hour. If you are a heavy sweater, if it is hot or humid out, or you are at altitude, you will need to increase your fluids accordingly. If this amount of fluid causes a sloshing stomach or makes you nauseous, it may be too much and we need to reevaluate your fluid needs per hour.

The goal is to minimize fluid losses to no more than 2-3% loss of body weight in fluids. This is where we start to see performance impacts such as fatigue, cramping, and gastrointestinal distress due to dehydration.

Add Some Electrolytes

Electrolytes include sodium, potassium, magnesium, chloride and calcium. Sodium is the electrolyte you lose in the highest concentration in sweat, so this is where you can place your focus when replenishing electrolytes. Sodium does not just function as an electrolyte. It also helps fluid balance and sugar transport across the small intestine, which prevents cramping, bloating, and bonking.

Sodium works like a key within the small intestine with a glucose (sugar) transporter (GLUT4). Without proper replenishment of sodium from outside fueling sources, there is a risk of not having glucose transporters open quickly enough causing a low concentration gradient in comparison to the blood plasma. This causes water to flows into the small intestine and can result in gas, bloating, diarrhea, and stomach cramping.

A good starting place for most endurance athlete is 300 -500mg of intake per hour. Athletes with a low sweat rate can stick to the low end, and sweatier folks, athletes racing at altitude or in the heat should aim for the higher end. You can get your sodium from a variety of sources including salt tabs, hydration mixes and foods (pretzels, potato chips, trail mix).

To Caffeinate or Not?

This is a hot topic! Caffeine is one of the most studied ergogenic aids and does have performance benefits; however, this is highly individualized. If you are someone that normally consumes caffeine and find you tolerate it well - no anxiety, no gastrointestinal distress, no jittery feelings - then you may feel ok having your normal cup of coffee before and/or using caffeinated gels on course. To note: caffeine does take 60 to 90 minutes to reach its peak in your system, so time caffeine consumption accordingly if you do plan to use it!

On the other hand, if you find you are more sensitive to caffeine and/or do not regularly consume caffeine I would not recommend caffeine on race day. Again, this is where simulating your race day in your training sessions comes into play.

Putting This to Practice

I am certain you have heard, "Do not try anything new on race day", and if you have not, I am telling you now! This is something I work on with my athletes constantly. You put weeks, months and, for some, years into your races. Do not let nutrition and hydration be the reason your race day does south. See my article on the reasons I see athletes DNF.

It is never to early to start practicing your nutrition and hydration strategy. Test out different sports nutrition products (gels, gus, and chews), try whole foods with a little protein for races over 3 hours, or try higher carb drink mixes. Any training day is great to test the waters and see what is palatable, flavors you enjoy, what sits well with your stomach and which make you perform your best.

As you are practicing it is also a great opportunity to understand when you want to utilize different products and how you prefer to carry them. For ultra runners (slower, steady state efforts), I have seen the whole gamut of nutrition choices from quesadillas to burritos to candy to sports drinks. For long course triathletes, you may tolerate solid food and enjoy something with more sustenance on the bike allowing for that last hour on the bike into the run to be liquid/ sports drinks or soft food nutrition (ie. energy chews or gels). For 5K to marathon runners and short course triathletes (harder/ faster efforts), you may enjoy and tolerate more soft food or liquid nutrition to support your efforts. If you are training or racing for longer than 60 minutes, you need to fuel during your session.

The name of the game regardless of what level or distance athlete you are is training your gut to tolerate nutrition and hydration. Read about this here. You want to practice the nutrition you are planning to use in your race during race-type efforts so that your body is familiar with that nutrition and know what to do with it. You may find in harder, higher intensity efforts that the nutrition you use in slower efforts does not work. Physiologically, the two energy systems being utilized are a little different and you will need to develop a tried and true plan for you.

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