Our body is like a car and needs energy to move forward. During an effort, the three necessary sources of energy are carbohydrates, lipids, and proteins. However, proteins, or more precisely amino acids from muscle breakdown, represent a very small percentage of the energy used during physical effort (less than 5%). The two main sources of energy are therefore carbohydrates and lipids, and the contribution of each of these energy sources depends mainly on the intensity and duration of the effort. The higher the intensity of the effort, the more carbohydrates become the main energy source used by the body.
If you are taking part in a competition, it is important to:
Make sure to replenish your glycogen (the carbohydrate reserve in your muscles) in the days before the race.
Consume enough carbohydrates during the race to have a constant supply of energy throughout the race.
Eat carbohydrates immediately after the race to replenish glycogen stores.
Nutrition before the race
If you are participating in a competition, especially one that lasts longer than 1.5-2 hours, it is suggested that you replenish your glycogen, which is commonly referred to as carbo-loading. The principle of carbo-loading is to increase the intake of carbohydrates in the 2-3 days before the competition, and particularly the day before the competition. It is therefore suggested to consume foods such as rice, pasta, potatoes, and bread. Also, the day before the competition, it is suggested to limit the intake of products that are difficult to digest such as fibre and fat.
On the morning of the race, it is recommended to eat a good breakfast 3-4 hours before the start. The meal should contain a lot of carbohydrates, some protein and very little fat. A good example of a pre-race breakfast is oatmeal with a banana, maple syrup, and a little almond butter. It is VERY important never to try something new the day of a race, so your pre-race breakfast should be the same breakfast you eat before your big workouts.
Nutrition during the race
During the race, it is suggested that you consume between 60 and 90 grams of carbohydrates per hour, which corresponds to 3 gels and some sports drink. Again, it is important to eat products that you are used to eating during your training to be sure that you can ingest a significant amount of these products during the competition.
It is also suggested to consume several types of sugars to optimize the rate of carbohydrate oxidation. Rather than just consuming glucose, it is suggested to consume products containing glucose, fructose, and maltodextrin.
Each type of sugar uses a different transporter in the intestine, so by consuming several types of carbohydrates, it is possible to oxidize a much greater quantity of carbohydrates during an effort. In fact, when only one type of carbohydrate is consumed during an effort, the maximum carbohydrate oxidation rate is about 60 g/h, whereas when several types of sugar are consumed, the carbohydrate oxidation rate increases to 90 g/h, and sometimes even more!
Also, the longer the event, the more important it is to vary the type of food ingested during the competition. For example, personally, during a half Ironman triathlon I can only consume gels and sports drinks. However, for an Ironman, I have a lot of difficulty digesting such a large quantity of gels, so I consume gels, jujubes (Clif Bloks), sometimes an energy bar, and even a banana. Since the intensity is lower in an Ironman triathlon, it is much easier to eat solid foods like a banana and an energy bar.
Fluids ingested during a competition serve to replace water and electrolytes lost in sweat, as well as to provide carbohydrates. The presence of carbohydrates and electrolytes promotes water absorption, so it is better to hydrate with a drink containing some carbohydrates and electrolytes than with water alone. Also, the concentration of carbohydrates in a sports drink should be between 4 and 6%. A concentration of more than 6-8% impairs fluid absorption and may cause discomfort. A concentration of 6% in a 750 ml bottle corresponds to 45 g of carbohydrates.
Nutrition after the race
After a race, it is important to ingest carbohydrates and drink fluids with electrolytes, especially when the temperature is high. Often after a race, it is difficult to eat food, so it is much easier to drink liquids with calories, such as a sports drink (e.g., Gatorade) or a soft drink such as Coke. Drinks or foods with a high glycemic index are recommended since they will be oxidized quickly and will replenish glycogen more quickly. Ingesting protein after a competition can also help with recovery, so drinking a protein smoothie or eating an energy bar with some protein may be recommended.
-Antoine Jolicoeur Desroches, Cycling Avenue Ambassador