Carbohydrates : Good or bad idea?

Like proteins and fats, carbohydrates are macronutrients. They are the main source of energy and are essential for the proper functioning of our body. Carbohydrates refer to all sugars. 1 gram of carbohydrates = 4 kcal.
Simple or complex, fast or slow, how do we differentiate between them?
What is their role, and how can they be properly used by athletes?

What are carbohydrates and how to differentiate them?

When we consume foods containing carbohydrates (rice-bread-pasta…), they turn into glucose and are then stored as glycogen in the muscles and liver. This glycogen becomes the primary energy reserve for athletes. If carbohydrates are consumed in excess through food, they turn into fat and are stored in adipose tissue.

Among these carbohydrates, we find simple carbohydrates and complex carbohydrates.
Simple carbohydrates consist of one or two sugar molecules (fructose and/or sucrose). Known for being quickly digested and used by the body, they have a high glycemic index (GI) (the ability of a food to raise blood sugar levels = glycemia).

On the other hand, complex carbohydrates consist of several sugar molecules, are absorbed more slowly, and have a low glycemic index (GI).

High GIs disrupt storage and energy production mechanisms and are harmful to athletes and their performance. Indeed, they create insulin resistance, which prevents glycogen from being properly stored and used by the body during exercise.
Consuming foods with a low GI, on the other hand, promotes fat use during exercise by stimulating insulin and helps increase endurance.

It is important to prioritize low or moderate GIs in your daily life, regardless of how close or far your next workout is. High GIs should only be used 30 minutes before and during your training on Kinomap.

Where to find low/moderate GIs:

• Basmati rice, whole-grain pasta, spelt
• Quinoa, buckwheat, sweet potato
• Fruits and vegetables
• Legumes (chickpeas, red beans, lentils…)
• Oats and barley

Where to find high GIs:

• Table sugar
• Honey, jam, maple syrup
• Processed sweet products (e.g., breakfast cereals or orange juice)
• Sweets, candies, pastries

Are carbohydrate needs different for athletes?

Carbohydrate needs vary between a standard person and an athlete. There’s also a difference between various sports (endurance sports and strength sports), as the muscles are used differently.

• Standard person: 40 to 55% of total daily energy intake.
• Endurance sports (triathlon, cycling, marathon…): 50 to 65% of total daily energy intake, which equals 5 to 12g per kg of body weight/day. For an endurance athlete weighing 75kg, this equates to between 375g and 900g of carbohydrates per day.
• Strength sports (weightlifting, combat sports…): up to 55% of total daily energy intake.

Total daily energy intake is individual-specific. It is calculated based on your age, sex, weight, height, and physical activity level (energy expenditure).

Some carbohydrate equivalents:

20g of carbohydrates equals:

• 40g of bread
• 30g of raw rice or pasta
• 1 banana or 2 apples
• 35g of lentils

How much carbohydrate to consume during exercise?

For short efforts (under 1 hour), glycogen reserves may be sufficient. However, if daily carbohydrate intake is too low, it is recommended to consume an energy drink, fruit paste, or energy bar during your session to avoid energy dips and hypoglycemia.

For efforts longer than 1 hour, it is necessary to eat regularly. Between 30g and 60g of carbohydrates per hour of exercise is recommended, to be adjusted according to your weight, individual gastric tolerance, and the intensity of the effort. For high-level athletes, this range can go up to 90g of carbohydrates per hour. More specifically, for intense and long efforts, 1g of carbohydrate/kg/hour is recommended.

Good quality carbohydrates provide energy in your daily life and your athletic practice. They are essential for the proper functioning of your body, just like proteins and fats.
The key is to have a balanced diet that fits your lifestyle and to listen to your body and its signals!

Chloé Masson
Nutrition Project Manager
chloemasson.nutrition@gmail.com

See previous nutrition articles:
WHAT TO EAT BEFORE A COMPETITION?
WHAT TO EAT DURING TRAINING?
WHY HAVE BREAKFAST?
WHAT DOES IT MEAN TO EAT HEALTHY? 
HOW SHOULD YOU EAT BEFORE TRAINING?
SPORT & HYDRATION: WHAT YOU NEED TO KNOW