It’s a matter of storing glycogen in your muscles before the big event, but if you are wondering which is best option for you, then read on as Radhika Meganathan discusses both approaches here. 

Every runner knows about and dreads hitting the “wall”, which happens when your body is depleted of energy, and energy comes from burning fuel, usually in the form of glycogen. To “load’ is to help your body fill up on its glycogen so that it can use it up for energy and keep you going as you are doing a long distance sport (anything that’s over 2 hours in duration). But what exactly should you load your body with – carbs or fat? Does it even matter?

Before answering this question, let’s first take a look at why glycogen plays a crucial role in the pre-race diet of a runner.

Why is glycogen important?

Let’s say you eat a delicious plate of biriyani or penne pasta. Once all those carbohydrates enter your system, most of it gets stored as glycogen in your muscles and liver. It’s like keeping money in a savings account; your body dips into it and you burn and lose energy during a race. So, the idea is to save enough glycogen to last an entire race. So now you have a free pass to eat whatever you want before the race, with no worries about dieting! All within certain reason, of course, as explained in the next part of this article.

What is Carb-Loading?

Simply put, you eat carbs before a race, ideally 3-4 days before the big day. This does not mean you just keep stuffing yourself without any limit. Eat to your satisfaction, not to the point of discomfort. The recommended range is to eat 7-10 grams of carb per kg of your body weight for 3 days before the race. Pasta, rice, bread, pancakes/waffles, chappathi, bananas, baked potatoes (without skin), oatmeal are in the recommended list Vegetables and fruits have carbs too but is best to keep them to a minimum, as they have fibre and too much fibre before a race can derail you with stomach issues!

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What is Fat Loading?

Now, glycogen is not the only source of energy your body has access to, it’s just the most easily digestible one! During a marathon, you burn both glycogen and fat. But the body has to work harder to convert fat into fuel, which is why it prefers to burn carbs than fat. Fat encompasses everything from meat to dairy to nutty oils – think bacon fried in butter or eggs sautéed in coconut oil. The one thing that is NOT present in fat loading is carbs, so all grains, fruits and sugars are out of this diet.

Carb Loading vs Fat Loading: Which is best?

There is no right answer to this question, as it is entirely a matter of what you want to do and which option is most suited to your body. From an economic perspective, foods used in carb loading are cheaper and easier to prepare. That said, a diabetic runner will certainly not take to carb-loading in a healthy way, and can benefit from fat loading which has almost zero carb content. If you are not insulin resistant, or if you are following a keto diet, you can certainly opt for fat loading about 9-10 days before the race.

Recent scientific studies have revealed that a fat-heavy diet can work for runners, as it teaches your muscles to be fat burners. So when you are trained to use fat as fuel during a race, glycogen storage is saved up for later use, resulting in an actual delay of “hitting the wall” – this means it can even be avoided completely. It does take a few weeks for your body to adapt to fat loading, so make sure you don’t experiment too close to the D-Day!

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A published author and an avid rambler, Radhika Meganathan is a recent keto convert who may or may not be having a complicated relationship with bacon and butter.

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