Endurance events take sports nutrition to a whole other level, as you are pushing your body well beyond a typical workout or training session. Failing to fuel your body during prolonged, intense physical activity won’t just slow you down—it can actually shut you down midstride.
During endurance activity, the body uses blood glucose, muscle glycogen, muscle triglycerides, and free fatty acids from fat cells to fuel performance. How the body uses these sources depends on the duration and intensity of the activity…
As intensity or duration increases, so does carbohydrate usage yet carbohydrates are in limited supply compared to fat. Unfortunately, using fat for energy is not metabolically efficient so when carbohydrate supply is limited, the intensity of exercise must decrease.
To avoid hitting the wall, as athletes say, the primary endurance fuel should be clean burning carbohydrates. Feeding your body carbohydrates alone, or along with a small amount of protein, helps maintain the body’s glucose levels reducing the reliance on muscle and liver glycogen stores which keeps you going faster and for longer. During long events like a marathon, the addition of a high quality raw fat like coconut oil can help the body efficiently use fat stores for energy as well, limiting muscle glycogen depletion. Coconut oil is a medium chain triglyceride metabolized in the liver to provide instant non-carbohydrate energy.
Just because you had a carbohydrate filled breakfast before the event does not mean it will sustain you for hours of physical activity. The body can only use a certain amount of carbohydrates at a time, about enough for roughly one hour of exercise depending on the intensity and duration. During intense activity, a good rule for replenishment timing is about 20 minutes before you actually need it and refuel every subsequent hour of physical activity.
When it comes to choosing an endurance aid it must be something you like and that your body can digest. The 2 main options are endurance gels or bars, and should be consumed based on personal preference. Gels are often easier for on the run digestion, while bars are a little more substantial and often provide a bit more protein for longer burning energy during tough workouts. Too many quick carbohydrates, artificial ingredients, or caffeine can cause gastrointestinal upset, the last thing needed during an event.
While most endurance products focus on glucose, hydration is also a critical component. Replacing electrolytes is needed during endurance events so that the nervous and muscular systems can respond to the increased demands, and because the body often loses electrolyte minerals through perspiration. Again, once you feel thirsty, you are past the point of needing water so ideally it is best to choose an endurance gel that also contains electrolytes, vitamins, and minerals so that you can hydrate and provide the much needed glucose in a small amount of liquid. The main electrolytes are sodium, potassium, chloride, calcium (phosphate), and magnesium; so choose a gel or drink that contains these minerals. Only drinking water during the event is not sufficient, as with too little sodium in the body a condition called hyponatremia occurs, leading to what is called water intoxication because the water is not actually entering the cells due to insufficient electrolytes.
Periodically, you challenge your body to go beyond the average workout, but you still want to leave it in good condition after an event so that you can be ready for the next challenge. When it comes to endurance, keep in the mind the 3 critical elements: fluid, electrolytes, and energy.