If you’re fortunate enough to be part of the expansive running community, you might be familiar with some of the buzzwords frequently used by runners. One such term is “Carb Loading,” commonly employed by seasoned runners, particularly during the taper phase, which is a period of time before a race during which runners reduce their training intensity and mileage to rest and prepare their bodies for peak performance on race day.

If you’ve found yourself wondering, ‘But why focus on carbs? Shouldn’t we prioritise a different macronutrient?’ You’re not alone. Before we dive into understanding carb loading, let’s first understand what carbs are and why they are essential for our bodies.

What are Carbs and What Do They Do? 

Carbohydrates are a major source of fuel for almost all body functions. They are a form of macronutrient, necessary for the body in large amounts, and are found in foods such as grains, fruits, vegetables, and dairy products.They play a crucial role in providing the body with energy to power vital functions like respiration, cognitive function, and muscular contraction and relaxation. Carbs are key for sustaining energy levels and optimising athletic performance

Why are Carbs the Main Source of Fuel?

Among the trio of macronutrients – carbs, proteins, and fats – carbs take centre stage as the body’s primary source of fuel, playing a pivotal role in ensuring that one is able to perform their best without ‘hitting the wall’, a sudden feeling of fatigue experienced during a race, too fast, too soon.

Now, a calorie can be defined as a unit of measurement used to quantify the energy content of food and beverages. Each gram of carbohydrate delivers roughly 4 calories per gram, while fats boast a hefty 9 calories per gram, and proteins fall in line with carbs at 4 calories per gram. However, in comparison to the other macros, carbs are easier to break down by the body owing to their biochemical structure, making them more readily available sources of energy. This allows for a rapid rise in blood glucose levels, which in turn leads to a surge in energy levels. 

Simple carbs include fruits, milk, and milk products. They are broken down quickly by the body to be used as energy. Complex carbs such as whole grains, rice, and lentils, on the other hand, lead to a gradual increase in blood sugar levels as they take longer to digest and breakdown to glucose, owing to their chemical structure.

Both simple and complex carbs can aid endurance athletes, especially runners, in their pursuit of improving their athletic performance; however, the timing, quantity, and type of carb consumed plays a vital role in the same.

What is Carb Loading? 

Elite athletes, especially those participating in endurance sports like marathons, triathlons, and ultramarathons, rely on various nutritional strategies to ensure their muscles can withstand the gruelling distances. One such strategy is called Carb Loading.

During longer races, runners require a higher amount of energy. Muscular glycogen, the molecular form of carbohydrates stored in muscles, acts as a readily accessible source of energy that enhances runners’ performance. Carb loading is a dietary practice that helps runners increase muscle glycogen levels by making alterations to their diet. This strategy is typically employed for activities lasting longer than 90 minutes. 

Typically, muscle glycogen reserves provide around 1,800 kilocalories of energy, enough to fuel about 1.5 to 2 hours of activity. During carb loading, runners consume more carbohydrates. The surplus of carbohydrates yields more calories, leading to an increase in stored energy, which enables individuals to sustain prolonged efforts and perform at their peak.

What should an ideal Carb Loading Plan look like?

A common practice in the past was to consume a large meal rich in carbohydrates such as rice, potatoes, or whole grains the night before a race, aiming to replenish the body’s glycogen stores. However, studies have shown that relying on one carb-rich meal alone is not sufficient. Instead, following a structured plan is far more beneficial.

Here are some key points to consider:

• Begin your carb-loading phase at least 2-3 days before the event. This allows ample time to gradually increase your carb intake and thus your glycogen stores.
• Increase your carbohydrate intake by 6-10 grams per kg of body weight each day. For example, if you weigh 60 kilograms, start with 360 grams of carbs on the first day and gradually increase to 600 grams by the final day.
• The aim is to obtain about 60-70% of your total daily calorie intake from carbohydrates, which may vary based on factors such as your age, height, weight, and gender.
• Opt for wholesome carbohydrate sources such as fruits, brown rice, sweet potatoes, potatoes, whole wheat or millet rotis, etc., instead of processed or “dirty” carbs like colas, candies, cookies, or pizzas.
• During this period, it’s best to steer clear of high-fibre and high-fat foods like green vegetables, nuts, seeds, and oily or spicy dishes, as they may lead to stomach discomfort.
• Note that the combination of reduced physical activity and increased carbohydrate intake may lead to temporary water retention, which can cause the weighing scale to tip to the right. Please keep in mind that this weight gain is a normal physiological response.

By following these guidelines, you can ensure that your Carb Loading Plan effectively prepares your body for optimal performance during endurance events.

Are there any downsides to Carb Loading?

While many athletes swear by this technique, it’s not all positive. Firstly, carb loading isn’t a one-size-fits-all solution. It works best for endurance events lasting more than 90 minutes, but it might not do much for short, intense activities like weightlifting.

Another factor to watch out for is picking the right carbs. Loading up on high-fibre carbohydrates could lead to some unpleasant digestive issues like bloating, gas, and even diarrhoea. So, opting for low-fibre carbs is a safer choice to prepare yourself the day before. 

The increased amount of carb consumption during the loading phase leads to an increase in blood sugar and insulin levels. Though this may initially give you a quick energy boost, when these levels drop you could be left feeling tired and lethargic.

Also, for every 3 grams of glycogen your body stores, it holds onto 3 grams of water. This means that the higher amount of carbs one consumes, the more likely they are to retain water and the more likely their body weight is to increase.

Lastly, for runners with conditions like diabetes or insulin resistance, carb loading might not be the best solution. Consulting with a dietitian or physician ensures that these concerns do not exacerbate further.

Now you have it – a brief yet comprehensive guide on carb loading for runners. By understanding the what, why, and how of this nutritional strategy, you can tailor it to meet your individual needs and optimise your performance. 

Whether you’re prepping for your first Half Marathon or looking to smash your Marathon PB, carb loading might be the missing puzzle piece in your race day strategy. Just remember, this technique isn’t an excuse to ditch balanced nutrition; it’s an essential element in the broader framework of sports nutrition that also includes hydration, protein intake, and recovery strategies. 

Now that you’re armed with this knowledge, happy carb loading and may the wind be always at your back!

REF:
https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/carbohydrate-loadinghttps://www.triathlete.com/nutrition/the-new-rules-of-carb-loading/https://www.issaonline.com/blog/post/everything-you-need-to-know-about-carb-loading-before-a-racehttps://ptandme.com/blog/carb-loading/https://www.weekand.com/healthy-living/article/disadvantages-carbohydrate-loading-18008238.php