There are three types of nutrition that you need during endurance training and racing:
1- Calories - mostly carbohydrates and fats Calories are your main source of energy. Calories from carbohydrates and fats are crucial for replenishing your glycogen stores. Glycogen is stored in the liver and the bonds of your muscle tissues. Glycogen is like the secret potion of energy-production that allows you to train or race for longer periods without hitting a wall. Unfortunately, glycogen depletes somewhere between 60-90 minutes of sustained energy output. You don't want to wait for that to occur before you begin replenishing. So, when should you begin to fuel? Pre training: It depends on your tolerance but an hour and a half to two hours is sufficient for a good bowl of white rice or anything equivalent of your preference. That way your body digests this food and converts it to glycogen so your gastrointestinal tracts are on the clear and not too busy giving you grief. Make sure you don't use fibrous foods because that would mean bowel movement and you want to limit that during a long endurance ride or brick. During training: It’s best if you eat every 20 to 30 minutes so the food conversion to energy is time-released enabling you to go for hours depending on the time and distance you are doing. Eating about 150 to 250 calories (depending on your weight and metabolic consumption rate) every hour is crucial to keep that energy flow. Post- training: The initial 30 minutes are crucial to replenish and restore all the nutrients you lost during the training bout largely because your metabolic system is in overdrive. So a good protein shake with ample amounts of carbs and minerals is highly recommended. Then an hour to an hour and a half later, eat a hearty meal that has sufficient carbs, protein and healthy fats to restore your body’s balance. 2- Fluids - second type of fueling. Why do you need fluids? When you’re doing an endurance event, there's a high demand put on your musculoskeletal and your endocrine system (which regulates your metabolism including sweat glands) and your central nervous system (coherence, balance and ability to have a clear mind). When you are training, your sweat is a signal of how much fluids you are consuming. It is true we don't see this during swimming for obvious reasons, but nevertheless, you are still burning fluids. Without this sustained flow of fluids, these systems will simply shut down. The first sign of this dehydration being painful cramps in your muscles. Most athletes who hit a wall during races are usually dehydrated. Before training: By the time you are hitting your training or race, you should have had between 20 to 30 Oz of fluids depending on your climate and your tolerance. Avoid training or racing on a dehydrated body; you will hit a wall. Also, you have to be careful not to overdo it to avoid hyponatremia, which can occur by drinking too much water which may result in great loss of sodium. During training and racing: Make sure you are constantly sipping away from your fluid bottles as you go. How much will depend on your need and the sweat-rate your body is registering. A good habit is to consume a between 20 to 30 oz of fluids every 60 minutes. If the temperature is hot, a little more than that maybe needed to prevent cramping and dehydration. Post-training: Make sure to continue with fluids after training to replenish and recover. 3- Electrolytes: Electrolytes are as crucial and paramount as carbohydrates and fluids and they can make or break your training and racing. These minerals are responsible for carrying out the critical functions such as muscle contractions and nerve impulse transmissions. When we talk about electrolytes, we are not talking about just salt, but a proper dosage of readily available supplements comprised of sodium, magnesium, potassium, calcium and chloride. When should you take them: Don't wait until you have started you training or race! Before training and racing: Start 30 minutes prior by using a balanced electrolyte supplement product that is designed for endurance sports. During training and racing: a continuous flow of electrolytes is crucial to keep your muscles relaxed and hydrated. A good habit is to mix your electrolytes with your water or sport drink so you get a triple whammy- carbs/fats, hydration and electrolytes supply all at once. There are several readily available supplements on the market that makes life so much easier by having all these supplements in one scoop or two for your bottle! After training and racing: Not as crucial, but a good, balanced meal after training and racing will do the trick.