Overview of Low Carbohydrates and High Fat (lchf) Diet

Recently, discussion has arisen over whether or not the low carb, high fat diet can impair exercise performance for elite athletes. A LCHF diet means you eat fewer carbohydrates and a higher proportion of fat, instead of foods like pasta and bread and low nutritional, sugary foods, you eat real foods including protein, natural fats and vegetables.

Low carbohydrates and high fat diets can have effects on metabolism and performance over a range of intensities at which endurance athletes train. Many argue whether the low carb, high fat diet is suitable for elite athletes. While studies prove that particular foods can help reduce food intake and cause weight loss, it has been revealed that a low carb, high fat diet can cause increased oxygen demand during exercise, reducing the amount of energy production required for maximal performance. These types of diets require an adaptation period of about one to two weeks, to let the body fully adapt to the new eating habits, which could have effects on the body and performance of elite athletes.

Studies show that the LCHF diet can reduce fat storage and increase fat burning, while preserving muscles mass so that improvements in body configuration are maintainable. The LCHF diet also known as the Ketogenic diet is derived from ketosis, a state in which the body enters when in starvation mode. When the body can no longer make glucose from carbohydrates, it resorts to eating off stored fats, resulting in weight loss. Athletes in ketosis can perform well at a steady endurance pace, while consuming fewer calories than those who are carbohydrate dependant. When athletes get faster after adapting to ketosis, weight loss is often a contributing factor to the increase in speed. this proves that the LCHF diet may be a good solution for long-distance, high endurance athletes wanting to improve speed.

However, while the low carb, high fat diet has been adapted by numerous athletes and sports professionals, opponents argue that athletes cannot get enough energy, reducing race times and performance. Professor Louisa Burke, Head of Sports Nutrition at the Australian Institute of Sport said ‘although the LCHF diet can increase the muscle’s ability to use fat as fuel source, there is lack of evidence to suggest that this diet improved sports performance’.

Studies showed that elite athletes excelled when consuming carbohydrates as opposed to those on the LCHF diet. Carbohydrates are a more economical fuel for the body and athletes who consumed carbohydrate targeted diets made performance gains after training whereas the group who consumed the LCHF diet failed to improve, thus suggesting that carbohydrates are more efficient at producing power for the muscles, therefore, the LCHF diet may not be suitable for elite athletes.