Fueling In and around the workout is the most important nutrition of the day and influences the workout they are in as well as future workouts and performance. What athletes don’t understand is that this also has a major influence on body composition. You aren’t just what you eat but when you eat it is also important. If you don’t want to know the “Why” skip to the bottom to the “How” section at the bottom.
If athletes don’t have the ability to have a meal 2-3 hours prior to their scheduled workout session it is imperative that they get started fueling just prior to the start of the workout. This timing should happen within the last 10 minutes prior starting the workout. This can be as simple as 6-8 ounces fruit juice, a gel with water, or starting their intra-workout nutrition formula.
An average size male athlete has absorptions rates between 30-90grams/hr during exercise. The upper end of this scale 90g can only be achieved with utilizing multiple delivery methods our bodies can utilize. We transport glucose and fructose via different transport systems. Knowing what is in your nutritional product is key and what you tolerate well is vital to your performance.
Endurance Athlete Fueling Options
There are many endurance fuel options available and an entire industry devoted to it. Glucose, fructose and maltodextrin are the primary ingredients that contain the calories of these fuel sources. The delivery methods come in powders that are mixed into liquids solutions, gel packets, bars, chewy candies etc… The delivery method to use is very individual. As intensity increases blood is shunted from the core of the body and shifted out to the working skeletal muscles. This slows the digestion process down significantly and may wreak havoc on a normally iron stomached person.
With under-fueling the dreaded “bonk” or “hitting the wall” technically called hypoglycemia may show up stopping an athlete in their tracks whereas on the polar opposite end of the spectrum over fueling in a short duration may lock up the stomach and shutdown all forward progress and leave you lying on the side of the course in the fetal position contemplating jumping in front of traffic to end the misery.
As the duration of your workout increases nutrition inevitably becomes more and more important. As any motor vehicle is limited by it’s efficiency and size of it’s gas tank the human body functions in a similar manner. We can store around 1hr-1.5 hrs worth of calories on board in the form of glycogen which we store in our skeletal muscles and liver. While we are working out and immediately post-workout we are very insulin sensitive and have the ability to not only shuttle nutrients we ingest almost directly into the liver and skeletal muscle but also supercompensate to a level that has an added benefit for future workouts.
Glycogen debt is a phenomena where athletes progressively dig deeper and deeper into a state of having less and less in the tank. We find that this leads to cravings outside the optimal window of nutrient timing which may lead to some of this eating be excessive and/or at a time that the athlete especially if sleep deprived or stressed where they may be insulin resistant where they literally can’t get the nutrients into the target cells and stored as fat.
In addition to the carbohydrate profile it is also important to have a electrolyte profile of your solution that still allows for an optimal osmoality to assure absorption without gastric distress. For carbohydrates a starting point for this would be to target at least 2 calories per lb of lean body mass. To do this calculation we need to also know that carbohydrates contain 4 calories per gram. If the food source has fiber with it we net out the fiber prior to doing the calculation. So if a food source has 20 grams of carbohydrates and 5 grams of fiber we have a net 15 grams of carbohydrates which would be 60 calories.
Example:
200lb @ 20% Bodyfat
200lbs x .20 = 40 lbs of fat
200lbs – 40lbs = 160 lbs of lean body mass
160lbs x 2 cals per lb per hour = 320 calories/hour
320 calories / hour / 4 cals per gram = 80 Grams
It is obvious that the simpler form that these calories are in the more readily they will become bioavailable and be efficiently processed. For this a fluid solution is our top option. Secondly, a gel with water would be another option.
Protein – while some athletes like to use protein during exercise as it gives them a bit of satiety we know that protein will also slow down the carbohydrate delivery. During the workout (especially races) and in the post workout recovery window solutions sans protein would be preferential. Yes so that post workout recovery protein shake should wait until we get a chance to get our carbohydrates replenished.
Immediately post workout we want to shift our blend to a more fast acting carbohydrate solution to take advantage of the cells being insulin sensitive at this time and to refill the gas tank of the liver and skeletal muscle. If it is a morning workout we have a caffeinated blend which we can use for a pick me up and should help shuttle nutrients a bit faster. We don’t want any caffeine after noon for our athletes that have a classic work schedule which would affect there sleep.
If this is an afternoon or evening workout we want to start fueling about 10 minutes prior to the exercise bout. 6-8 ounces of orange juice for example is not only good for the liver but will get some fructose in the mix. Follow this by starting your Intraworkout and continue through the entire workout.