Everybody is talking about carbohydrates, or carbs as they are commonly called. Your body requires carbs to provide it with energy and it is good at making efficient use of them. The macronutrient can be burned with (aerobic) or without (anaerobic) oxygen. Fat, on the other hand, always requires plenty of oxygen. Plus, it takes twice as long to provide the same amount of energy as carbohydrates. That is why we have to reduce our pace and breathe more deeply or rapidly when we want to burn fat while running. This is also when it starts to hurt. You might catch yourself thinking that the couch looks awful comfy right now. Or the question “What the hell am I doing?” keeps popping into your head. But once you have conquered these mental hurdles, things will start to get easier.
Your body stores carbs in the form of glycogen in your liver and muscles. They are important energy reserves — especially for ambitious runners. The more glycogen you have stored in your muscles, the higher and longer they can perform.
Better, faster, farther
In general, the following nutrient ratio is recommended for endurance athletes:
Carbohydrates 55-65%
Protein 10-15%
Fat 25-30%
Carbs are your muscles’ fuel. The macronutrient is very important for runners looking to enhance their performance (for instance, for a marathon) — not only before workouts, but also after you finish running. If you refill your glycogen stores right after a run, your body will recover faster. This helps your body adapt better to a new or harder workout and builds up your immune system faster again after your training. The more often or intense you train, the more important a diet rich in carbohydrates is to your recovery.
The right window of oppurtunity
The best time for your body to replenish its glycogen stores is within the first 30 minutes after your workout. Runners should use this half hour to eat simple carbohydrates like fruit, cereal, bread with jelly, or pretzel sticks. These carbohydrates are easy to digest, and the body absorbs them quickly. After 30 minutes, the window starts to gradually close, and your body is no longer able to absorb carbs as efficiently and quickly. The amount of carbs you need depends on your body weight and the intensity of your training:
- low intensity 0.5-0.7 g of carbs per kg of body weight
- medium intensity 0.7-1 g of carbs per kg of body weight
- high (maximum) intensity 1-1.2 g of carbs per kg of body weight
The evening meal after your run
An hour after your run, you should eat a full meal with carbs, protein and fat. To be more exact, your meal should contain a 4:1 carbs to protein 
ratio. Carbs are still important at this point, but your body also needs protein to build muscles. Too much of this macronutrient, however, can interfere with efficient absorption of carbohydrates and disturb your body’s fluid balance.
Good post-run meals are, for example, a kidney bean wrap, fish with potatoes and vegetables, or pasta with chicken breast.
