how much carb loading before marathon

Carbohydrate loading, commonly known as carb loading, is a popular nutritional strategy among endurance athletes. The goal of carb loading is to maximize the amount of glycogen stored in the muscles, which serves as a primary fuel source during exercise. In the context of marathon running, carb loading can help athletes maintain their pace and delay fatigue. However, there is much debate among experts and athletes regarding the optimal amount of carbohydrate intake before a marathon. In this article, we will review the scientific evidence and provide practical recommendations on how much carb loading is necessary before a marathon.

What is carbohydrate loading?

Carbohydrate loading is a dietary strategy that involves manipulating the intake of carbohydrates in the days leading up to an endurance exercise event. The goal of carb loading is to increase the storage of glycogen in the muscles and liver, which can provide a readily available source of energy during exercise. Carbohydrate loading typically involves reducing physical activity and increasing carbohydrate intake to 7-12 g per kg body weight per day. The increase in carbohydrate intake can come from a variety of sources, including bread, pasta, rice, fruits, vegetables, and sports drinks.

The science behind carbohydrate loading

The scientific evidence behind carbohydrate loading is well established. Studies have consistently shown that carbohydrate loading can increase the amount of glycogen stored in the muscles and liver by up to 50%. This increase in glycogen stores has been shown to improve endurance performance, delay fatigue, and improve time to exhaustion. The exact mechanism behind the performance-enhancing effects of carbohydrate loading is not fully understood, but it is thought to involve an increase in the availability of carbohydrate fuel during exercise, which can help spare muscle glycogen and delay fatigue.

How much carbohydrate should you consume before a marathon?

The optimal amount of carbohydrate intake before a marathon is highly individualized and depends on a variety of factors, including body weight, training status, and genetics. However, in general, most experts recommend consuming 7-12 g of carbohydrate per kg of body weight per day in the days leading up to a marathon. For example, a 70 kg (154 lb) athlete would need to consume between 490-840 g of carbohydrate per day in the 2-3 days before the marathon. It is important to note that carbohydrate loading should be done in conjunction with reducing physical activity, to allow the muscles to store as much glycogen as possible.

Practical recommendations for carbohydrate loading

Carbohydrate loading can be a daunting task, but with careful planning and preparation, it can be done effectively. Here are some practical recommendations for carbohydrate loading before a marathon:1. Start carb loading 2-3 days before the marathon2. Reduce physical activity during the carb loading period3. Consume between 7-12 g of carbohydrate per kg body weight per day4. Focus on eating complex carbohydrates, such as whole, unprocessed grains and vegetables, as they provide sustained energy5. Don't overdo it on simple sugars and processed foods, as they can cause rapid spikes and crashes in blood sugar levels.

Conclusion

In conclusion, carbohydrate loading is a tried and true nutritional strategy for endurance athletes, particularly marathon runners. The goal of carb loading is to maximize the amount of glycogen stored in the muscles, which can help athletes maintain their pace and delay fatigue. While the optimal amount of carbohydrate intake before a marathon is highly individualized, most experts recommend consuming 7-12 g of carbohydrate per kg of body weight per day in the days leading up to the marathon. With careful planning and preparation, carb loading can be done effectively and help athletes achieve their marathon goals.