Dana Eshelman, MS, RDN, CSSD, METS I
An ultra endurance event is classified as any race lasting six hours or more; some of these events can go for days or weeks. Athletes may race in running, cycling, swimming, cross country skiing or a multi sport event such as triathlon where athletes compete for covering a certain distance in the least amount of time or covering the most distance in a set time frame. In any case, this duration of an event in any sport, there are special nutrition considerations to be aware of:
Consuming enough total calories
Familiarizing your gut in training sessions to tolerate food, fluids, and carbohydrates
Regulating fluid balance
Understanding your unique electrolyte needs
Combating flavor fatigue
Total Calorie Intake
Getting enough total nutrition during multi day events is crucial for stable energy. You will want to train your gut to tolerate more fuel during training in an effort to work toward 400 calories/ hour (or more) based on individual needs. Your energy requirement will vary based on fitness level, weather, altitude, elevation gain/ loss along the route, and various other factors. For ultra endurance athletes, I often see calorie intakes range from 3,500 to upwards of 8,000 calories/day from a combination of carbs, protein, and fats. The key is starting small, around 200 calories/ hour, and gradually increasing your intake to meet your personal calorie needs.
Carbs are KING! These guys provide you with the energy your working muscles need to perform. Research shows that sports nutrition products containing multiple transportable carbohydrate solutions are highly effective forms of energy during endurance racing and training. For example, for events lasting >2.5 hours including 60 to 90 grams of carbs per hour with a 2:1 ratio of glucose: fructose or maltodextrin: fructose. Again, starting small if you are an athlete that comes from not fueling your sessions and building your tolerance.
Cluster dextrin is another source of carbohydrate for ultra endurance athletes that is gentle on the stomach, provides more stable energy release, has less of a sweet tastes/ limits flavor fatigue, and encourages fat oxidation. For races that are six plus hours, you are going to be moving at more of a steady state, think zone 1- low zone 3, meaning you are predominately going to be using fat for fuel (This does not mean you do not need to intake carbohydrates. Your body is still using some carbs. More on that topic another time). In this scenario, using a fuel source with cluster dextrin may be a reliable option.
There are a load of sports nutrition products out there. I encourage you to try a few different options that provide a variety of carb sources and write down what combination of carbohydrates works and what does not work for you. You may also use whole foods (see below) to add variety in your fueling strategy.
Protein has many functions in the body. It provides the building blocks to build and restore body tissue, it maintains pH and fluid balance, it protects against disease, it regulates passage of substances across the cell membrane, and it coordinates cell signaling pathways. As an endurance athlete, these are all very important due to the muscle breakdown that occurs, especially in multi day events.
The International Society of Sports Nutrition recommends endurance athletes consume 1.4 to 1.6 grams of protein per kilogram of bodyweight. This can range up to 2 grams of protein per kilogram of bodyweight in peak phases of training. For a 150lb (68 kg) athlete, protein intake can range from 95 to 136 grams of protein per day. Including 5 to 10 grams of protein per hour during ultra endurance events can decrease muscle protein breakdown that occurs with long duration training and racing.
If your event follows a stage race format, consuming 0.3 g protein per kilogram body weight in the 30 minutes post race and again before bed, this will aid in recovery for the upcoming day's of racing!
Dehydration as well as hyponatremia (aka low blood sodium concentration) are well known factors for negatively impacting performance and, in the most extreme cases, can be life threatening.
Your sweat rate is individual to you and can vary based on environment (heat, humidity, cold, altitude), genetics, metabolism, age and gender, and intensity and duration of session. I highly recommend understanding your individual sweat rate in the conditions you will be racing so you can decrease incidence of dehydration and/or over hydration, which is equally as dangerous. A simple way to find your sweat rate:
Pre run weight (kg) ___ (lbs/ 2.2 = kg)
Post run weight (kg) ___ (lbs/ 2.2 = kg)
Pre run (kg) - Post run (kg) = Change in body weight (grams) ___ (kg x 1000 = g)
Volume of fluid consumed (mL) ___ (oz x 30 = mL)
Change in weight (g) - Fluid consumed (mL) = Sweat losses (mL) ___ (1 g = 1 mL)
Exercise time (min or hr) 60 min
Sweat Rate = sweat losses/ exercise time
Another important consideration in the ultra endurance space is that as you become dehydrated, the rate of absorption of carbohydrate in the small intestine SLOWS DOWN. Meaning, delivery of nutrients (aka energy) is stalled. This could be a huge set back in a multi day event.
As a guide, drinking fluids (preferably with electrolytes) at a rate of 5 to 8 ounces every 15 to 20 minutes can minimize the risk of dehydration and heat stroke. You may need to increase this based on your individual sweat rate and/or environmental conditions.
Within sweat, you are not just having fluid losses, you are also losing electrolytes. The primary electrolyte lost in sweat is sodium. On average sodium losses in sweat range from 0.25 g/L up to 2g/L. You will also see smaller losses of magnesium, potassium, calcium, and chloride. Replenishing with a full spectrum electrolyte solution is equally as important as replacing fluid losses as they play an important role in maintenance fluid balance, prevention of hyponatremia, function of the nervous system, and function of muscle and organs.
To find your sodium concentration in your sweat losses, you can use something like the gatorade sweat patch. You may also already know if you are a "salty sweater" due to the salt residue that stays on your clothes and/or skin after training or racing, if you are craving more salty foods, you suffer from muscle cramps, you struggle with lightheadedness/ feeling faint, and/or you feel terrible after exercising in the heat.
Just as with carbs and calories, start small. Including 400 to 600 mg sodium solution (ie sports nutrition powder) per liter is a great place to start for low sodium losses or if you are not fueling with electrolytes currently. You may titrate your sodium solution up based on individual needs.
Combat Flavor Fatigue
You have been there when you are consuming too much sweet stuff -- sports nutrition drinks, gummies, gels, a candy bar-- that the thought of drinking another sip of your electrolytes or taking in another gel makes you nauseous. In any race, this is less than ideal because you need both the fluids and the calories to move forward successfully.
Including some real food and unflavored or lightly flavored sports nutrition beverages as a part of your plan can decrease the fatigue from all the sugary stuff. Take a moment to have something more savory (& what a great way to get protein in) and include this as a part of your plan. Some examples of savory snacks that include carbs, protein, a little fat and sodium:
Savory rice cakes -- for example: 2 c sticky rice, 3 c water, 4 eggs, 2 sl bacon, 2 T coconut aminos, a dash of brown sugar, top with grated parmesan cheese. Cook rice. Scramble eggs and bacon in large skillet. Add cooked rice to egg mix. Add coconut aminos and cheese. Stir until combined. Spread over cookie sheet to ~1 inch thick. Cut into squares to take on the go.
Earth's best food pouches
Justin's Peanut Butter Packs
DIY trail mix - pumpkin seeds, walnuts, almonds, cashews, chocolate pieces, dried fruit
Practice, Practice, Practice
Train as you race. Period. Your gut is highly adaptable and providing it with the resources you need to train, recover, and do life outside of training and racing is key to being successful in these longer races. Developing a tried and true plan for your nutrition and hydration/ electrolyte intake is key to have the confidence in executing a strong race!
Nutrition is what makes the difference between a good athlete and a great athlete. The time and dedication you spend in training needs to be reciprocated in how you are supporting and nourishing your body! Especially in multi stage racing. There is a lot of opportunity to provide your body with the tools it needs to replenish and refuel so you can finish the race as strong as you started! There is also a lot of opportunity for missing essential nutrition along the way, which can result in a DNF (did not finish).
Train smarter by optimizing your fueling and hydration strategy.
If this is something you need help with, ask your fellow sports dietitian to help you improve your knowledge on developing a strategy that is best for you! That is what I am here for :)