Carbohydrates: Train Like a Pro, Race Like a Champion
on November 14, 2022
Carbohydrates as a primary source of energy
As we have discussed in the previous article, nutrition plays a vital role in exercise. Today we will discuss one of the primary macronutrients that are a source of energy for most activities, especially when running a marathon. Furthermore, I will give examples of breakfast for Race Day and food after the race.
Let's start from the basics. What are carbohydrates? They are molecules composed of carbon (carbo), hydrogen, and water (hydrate). These are divided into monosaccharides, disaccharides, polysaccharides, and fiber.
The monosaccharides are the most basic component of carbohydrates, within which we have glucose (sugar in grapes), dextrose (sugar in fruits), and galactose. We find these in our daily diet, with glucose being the main used and galactose the least.
The disaccharides are made of two monosaccharides, with the most important being lactose (which comes from milk), sucrose (table sugar, sugar cane, beetroot), and maltose (malt sugar).
Polysaccharides are the more prominent compounds. Within them, we find starches, glycogen, and fiber, the primary forms of storage of carbohydrates in our bodies.
Muscle glycogen is the primary source of fast energy and is easy to obtain for the working muscle. The rate at which this oxidates largely depends on the intensity of the exercise. However, the hepatic glycogen's primary function is to stabilize the blood glucose levels, which is the brain fuel.
In general, athletes train daily, which means it is crucial to replenish muscle glycogen. In 1970, scientists discovered the relationship between the ability to perform strength training and the body's glycogen reserves before starting the exercise and that a carbohydrate-rich diet increased these reserves. Years later, Achten et al. (2004) observed that increased carbohydrate consumption could help reduce overtraining symptoms such as changes in mood and fatigue.
Scientists recommend that the amount of carbohydrates we should be consuming should be calculated from the body weight and the amount of training (COI 2011; ACSM/ADA/DC2009; Burke et al. 2004) since the glycogen storage capacity is more or less proportional to the muscular mass and body weight.
Depending on the exercise intensity, the recommendations are as follows: (Burke, 2007).
Moderate training intensity (1 hour of training per day) 5-7g/kg of body weight daily.
Moderate to high training intensity (1 to 3 hours of training per day) 7-12g/kg of body weight per day
Very high training intensity (more than 4 hours of training per day) 10-12g/kg of body weight per day
It is worth mentioning that the food's glycemic index will influence how fast or slow these are absorbed. I will leave you with a list of some foods depending on their glycemic index below:
Foods with a high glycemic index: White bread, boiled or oven-cooked potatoes, cooked white rice, gummies, watermelon, and pastry.
Foods with a moderate glycemic index: Bagels, donuts, 250ml of beer, toasted white bread, ice cream, energy bars, honey.
Foods with a low glycemic index: potato chips, cookies, chocolates, 250ml of orange juice, muesli, apples, whole milk, tomatoes, lentils, spinach, broccoli, and asparagus.
Lastly, the combination of these types of carbohydrates consumed during exercise or a race will also influence a greater acceptance and absorption of these to enable you to continue with energy and reach your goal.
Regarding the ingestion of carbohydrates before exercising, the recommendation is to do so between 3 to 5 hours before starting to ensure glycogen is replenished in the liver after the nightly fasting. This should ideally be a food rich in carbohydrates (140g to 300g), for example:
A big bowl of porridge with skimmed milk, one banana, and a 250ml glass of orange juice. You can also add a cup of coffee if you wish.
2 to 4 slices of toasted bread with jam or honey, a coffee with skimmed milk, and a small bowl of fruit salad
Yogurt with dried fruit compote (Apricots, plums without peat, raisins), 1 cup of black coffee
The primary objective of ingesting carbohydrates after exercise is to replenish the storage of glycogen both in the muscle and in the liver. The main factors that ensure this replenishment is optimal are:
The rhythm at which the carbohydrates are ingested
The speed at which they are ingested
The type of carbohydrates
The ingestion of proteins alongside the carbohydrates
The ingestion of caffeine
Studies show that we should consume foods with carbohydrates in combination with proteins in the first hour after exercising in a 3:1 or 4:1 relationship (1g of CH/Kg of weight with 0.3g of protein/kg of weight). Six hundred grams of carbohydrates within the next 24 hours are well distributed, and 200g of protein.
For example, as soon as you finish a race, you could eat a banana with some dried fruit snacks or some recovery with different nutrients our body needs, as long as you are going to eat a bigger meal in the next few hours, such as a plate of paella with seafood. This gives you a good amount of carbohydrates with a high glycaemic index, and alongside the proteins from the seafood, you will have a good amount of omega 3. Another option could be a pasta wok with salmon, vegetables, and teriyaki sauce, which, alongside the previously mentioned, will replenish minerals such as sodium and some vitamins from the vegetables. Lastly, we could grab a dessert containing some berries and some antioxidants to reduce the free radicals. Most importantly, don't forget to drink plenty of water throughout the day.