Is Carbo Loading Necessary For Peak Race Performance?

The concept of "carb loading" for endurance events like marathons and triathlons is ingrained in our sport. But how do you know if you're eating too much for energy and starting to gain fat?

We all know about carb-loading (for some people, it's the most fun aspect of taper week!), but most people go overboard, unwittingly eating far more than their body needs or can even store. What happens? They put on fat, which only serves to slow them down. Here's how to get it right.

• Why Do We Carb Load? 
• By eating more carbohydrate foods in the lead-up to an endurance event, we fill our glycogen stores (in the muscles and liver) with the energy our body needs to keep going. Because we can only store a certain amount of carbohydrate/glycogen in the body, we aim to maximise the amount so we don't crash, bonk or "hit the wall".
• How Does The Body Use Carbs? 
• During an endurance event (anything over 90 minutes in duration), our bodies use on average 60g carbohydrate per hour. That's why energy gels, blocks and drinks are created with certain levels of carbs. But 60g carbs is only 240calories. Even the lightest athlete will use far more than 240 calories per hour during their race. So the extra energy needs to come from somewhere… our own glycogen stores.
• How To Carb Load The Smart Way? 
• If you're used to chowing down on a huge bowl of pasta the night before the race, you need to start thinking about carb loading differently. A better way to do it is to slowly drip-feed your body extra carbs for 48-72 hours before the event. Note that this doesn't mean eating as much bread, pasta, rice and sweets as you can! This will at best get stored as body fat, and at worse play havoc with your digestive system, leaving you in trouble on race day!

Aim for 3.5 to 5.5 grams of carbohydrate per pound of body weight and use carbohydrate foods you know you can tolerate. Now is not the time to try ingredients or dishes you haven't had before. Go for healthy options like potatoes and starchy root veg, rice, oats, pasta and breads, but leave out anything you know does not agree with you. If you are having a hard time getting the carbs in, by all means use sports drinks, jelly sweets, honey or jam.

Keep fats and fibre relatively low (fat slows down the digestion of carbs, and adds extra calories which you don't need whilst you are eating more from carbs. Fibre is healthy, but too much of it can cause digestive issues, and you don't need that right now!) And don't worry if your weight shoots up when you carb load. Remember the "hydrate" part of "carbohydrate" - for each gram of glycogen, your body stores around 2 grams water…

Pair your 2-3 day carb load with your natural taper off in training, and you will achieve the boost in muscle glycogen that you need. Good luck and happy racing!!!