Words of Appreciation. Carb loading is a dietary approach used by athletes that involves consuming a high-carbohydrate diet, usually 1 — 3 days prior to a long-duration endurance event to increase glycogen stores in their muscles as part of the preparation process.

Such events include marathons, long-distance road cycling, long-distance swimming, or if athletes are playing a tournament with back-to-back games, such as during basketball championships or soccer tournaments.

Modifying diet and exercise routines aims to create a larger "fuel tank" of stored muscle glycogen, our body's preferred energy source during prolonged, high-intensity activity.

Carbohydrates, often referred to as carbs, are one of the primary macronutrients, alongside proteins and fats, vital to our bodily functions. They are the body's main energy source, supplying the energy that our cells require to carry out their daily functions.

Carbohydrates are made up of small molecules of sugars, or saccharides, that when combined in various ways form different types of carbohydrates. Based on their structure and complexity, carbohydrates can be divided into 3 main types. Simple carbohydrates sugars. Simple carbohydrates, also known as sugars, consist of one or 2 saccharides — monosaccharides or disaccharides.

Examples of sugars include glucose, sucrose, and fructose. They are quickly absorbed and provide a rapid source of energy. Sugars are found naturally in fruits, milk and milk products, and simple sugars are also added to a variety of processed foods and drinks like sweets and soft drinks.

Complex carbohydrates starches. Complex carbohydrates, or starches, consist of many saccharide units linked together and are found in foods such as potatoes, bread, rice, and pasta.

These carbohydrates are digested more slowly than simple sugars, providing a more sustained energy release due to their lower glycaemic index. This is particularly true of starches that contain fibre e. wholemeal bread, potatoes with skin, and brown rice.

Dietary fibre. Dietary fibre is a type of carbohydrate that our bodies cannot digest. There are 2 types of fibre: soluble, which dissolves in water and can help lower blood glucose and cholesterol levels, and insoluble, which can help food move through your digestive system, promoting regularity and helping prevent constipation.

It is important to understand the different types of carbohydrates and their roles to better optimise dietary strategies such as carb loading, to improve athletic performance. Carb loading is primarily intended for endurance athletes preparing for prolonged, intensive events, typically those lasting 90 minutes or longer.

This is because such strenuous activities deplete glycogen stores in muscles, which could result in fatigue and reduced performance. By carb loading, athletes aim to maximise their glycogen storage, which can enhance their endurance and delay the onset of fatigue.

Examples of activities where carb loading may be beneficial include marathon running, long-distance cycling, triathlon events, and long-distance swimming. However, it's less relevant for sports involving short bursts of activity, such as sprinting or weightlifting, and for activities of a lower intensity or shorter duration.

While carb loading can be beneficial for endurance athletes, it's important to note that it should be approached with care. Not every endurance athlete will respond to carb loading in the same way, and individual dietary needs can vary widely. Carb loading primarily benefits athletes by enhancing their endurance.

By maximising muscle glycogen, the body's preferred form of carbohydrate during exercise, athletes can maintain a high level of exertion for longer periods during endurance events, thus delaying the onset of fatigue. Consuming glycogen after exercise helps replace muscle glycogen depleted during exercise, and aids in storing more glycogen as an adaptation to training.

This is especially beneficial when events are spaced closely together — generally, if events are less than 8 hours apart. The importance of carbohydrates extends beyond physical performance to mental acuity as well.

Sufficient carbohydrate intake fuels the brain, aiding in maintaining focus and decision-making during endurance events. Research suggests that consuming a high carbohydrate intake prior to a long-duration endurance event may delay the onset of fatigue and reduce risk of injury, further boosting the athlete's capacity for sustained performance.

However, carb loading strategies should be personalised, as individual needs and responses can vary greatly. Timing is crucial when it comes to carb loading. Begin the process approximately 36 — 48 hours prior to your event.

This timeframe allows your body to store glycogen, the primary fuel source during prolonged exercise. To determine the right amount of carbohydrates to consume, it's advisable to consult with a sports dietitian.

They can assess your individual needs and recommend a specific daily intake. Generally, athletes are advised to consume around 8 — 12 grams of carbohydrates per kilogram of body weight per day during the carb loading phase. In conjunction with increased carbohydrate consumption, it's important to implement an exercise taper during this period.

Reducing the intensity and volume of your workouts allows your muscles to recover and glycogen stores to be maximised. A useful tip would be to practise carb loading as part of training prior to the actual competition or event. This will allow you to experiment with different strategies, gauge their effectiveness, and make any necessary adjustments.

By doing so, you can optimise your performance and fuel your body effectively for the endurance challenge ahead. It's important to note that carb loading protocols may vary among athletes.

To develop a personalised plan, it is recommended to discuss your specific needs with both a sports dietitian and physical trainer. They can guide you through the process, fine-tuning the dietary and training aspects to suit your individual requirements.

Carb loading doesn't mean you should increase your total daily calories. Rather, it involves adjusting the proportion of your calorie intake that comes from carbohydrates. Overeating can lead to weight gain and feelings of heaviness or discomfort, which are not conducive to optimal performance.

Do not neglect to consume sufficient fluids prior to an endurance event to ensure that you are adequately hydrated. Failing to properly hydrate can lead to dehydration and negatively impact your performance and recovery. Another common mistake is not consuming enough carbohydrates to maximise glycogen stores.

For effective carb loading, aim for 8 — 12 grams of carbs per kilogram of body weight each day. The exact amount of carbohydrates required prior to an event should be discussed with a sports dietitian, as this will vary across different individuals and different types of sport.

This can come in the form of refined carbohydrates like bread, rice, and noodles. Although foods and drinks high in refined sugars, such as smoothies, cereal bars, and flavoured milks are generally not recommended on a regular basis, it is acceptable to use these foods and drinks to meet the higher-carbohydrate demands of carb-loading prior to endurance events.

Some athletes consume too much fibre while carb loading, leading to gastrointestinal discomfort. In the final days leading up to the event, switching to low-fibre carbohydrate sources such as white bread instead of wholemeal bread, or regular pasta rather than wholegrain pasta can help alleviate potential digestive issues.

Some people make the mistake of consuming high-fibre or fatty foods during their carb loading phase. There are many forms of carbohydrates:.

Think of mono- and disaccharides as simple carbs, with oligosaccharides and polysaccharides as complex carbohydrates. The simpler a carb is, the quicker it will be broken down and used by the body as energy.

Simple carbs will result in a rapid rise in blood glucose and insulin secretion from the pancreas; complex carbohydrates take longer to digest and will result in a steadier rise in blood glucose.

Carb loading involves an athlete topping up their muscle, blood, and liver glycogen carbohydrate stores by consuming a very high amount of carbohydrates in the days leading up to a race. Unfortunately, their particular approach required three days of exhaustive exercise combined with three days of high-carbohydrate fueling, which is hardly the pre-race taper many of us adhere to now.

High glycemic foods are those that are ranked highly on the glycemic index: they are foods that are rapidly digested and absorbed and cause a sharp rise in blood sugar e. One of the biggest mistakes athletes often make when approaching carb loading is failing to practice it in training.

Ideally, an athlete will practice carb loading going into race simulation workouts a few times before race week. This allows the athlete to assess reaction to the higher carbs, practice eating the actual prescribed carbohydrate amounts, and decide which foods are best tolerated.

Practicing the carb load is absolutely crucial, but doing dry runs of the pre-race breakfast and the in-session race fueling is equally as important. Rehearsing these strategies will provide familiarity and confidence that a fueling strategy is on point when it comes to race day.

RELATED: Ask Stacy: What Makes a Good Pre-Race Meal? For women, there is a dearth of research investigating carb loading related to race-like conditions. The majority of studies have focused on the percentage of energy intake i. However, the studies did not determine whether the total energy consumed on a daily basis actually met the demands of training and racing.

There are a few studies that have investigated loading in women using a high enough amount e. However, this concept has been debated. Furthermore, the type of carbohydrate, timing, and the amount that each athlete requires for optimal performance is unique to them.

If you choose to carb load before an event, you will still likely need to supplement more carbohydrates during the activity.

Carb loading might be an effective strategy for those looking to boost performance during prolonged, intense activity. Consuming more carbohydrates along with reduced activity for a few days before an event might preserve and load the body with energy stores in the form of glycogen.

However, this strategy is not necessarily going to work for everyone, and the type, timing, and amount of carbs required will be unique for each person. Other factors such as recovery, fitness level, and hydration can also affect performance.

Experiment with carb loading before a big competition to determine how your body responds. Canadian Academy of Sports Nutrition. Carbohydrate loading. Kanter M. High-quality carbohydrates and physical performance: Expert panel report. Nutr Today. Kerksick, C. et al. International society of sports nutrition position stand: nutrient timing.

J Int Soc Sports Nutr 14, 33 Mata F, Valenzuela PL, Gimenez J, et al. Carbohydrate availability and physical performance: Physiological overview and practical recommendations. Burke LM, Hawley JA, Wong SH, Jeukendrup AE.

Carbohydrates for training and competition. Journal of Sports Sciences. By Rachel MacPherson, BA, CPT Rachel MacPherson is a health writer, certified personal trainer, and exercise nutrition coach based in Halifax. Use limited data to select advertising. Create profiles for personalised advertising.

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By Rachel MacPherson is a health writer, certified personal trainer, certified strength and conditioning specialist, and exercise nutrition coach based in Halifax.

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