Ketogenic Diets and Sport Performance

Athletes and other sports people use many weight reduction methods but most of these methods negatively influence physiological efficiency during sports performance. Many gymnasts and body builders use the so called very low carbohydrate ketogenic diet (VLCKD) that has shown to be a safe weight loss diet tool which does not affect muscle strength or muscle size. However, not much research is available on this subject.

So, Antonio Paoli at the University of Padova, Italy, and his colleagues recruited 8 elite artistic gymnasts and analyzed their body composition and various performance aspects before and after 30 days of a modified VLCKD that included green vegetables, olive oil, fish and meat and other almost-no-carbohydrates but high quality protein dishes.

They found significant reduction in body weight and fat mass with a non-significant increase in muscle mass.

The study has been published in the Journal of the International Society of Sports Nutrition.

Most physicians and nutrition scientists say that carbohydrate must constitute a major component in our daily diet in those people who are involved with hard core physical exercise. This view is based on a long list of published studies that were performed over the last century that links muscle glycogen stores to high intensity exercise. It has also been reported that people who consume diet deficient in carbohydrates experience light headedness, weakness, and ease of fatigue.

Glucose is the simplest form of carbohydrates, but when several glucose molecules are linked together in chains, they form complex carbohydrates. They are responsible for providing energy throughout the day.

The principle behind ketogenic food in the diet is that low carbohydrate intake will force the body to burn its fat reserves as an alternative source of energy. The diet mimics the aspects of starvation. It derives the name from the organic bodies that are known as the ketone bodies that are synthesized by the conversion of the fatty acids in the liver when the glucose availability is limited. This usually happens when the daily carbohydrate intake is less than 30g.

When the source of glucose is not available as the immediate energy source, the ketone bodies can replace glucose as a source of energy. This is especially important for the brain that predominantly uses glucose for energy.

Studies have shown that ketogenic food items being extremely low in carbohydrates push the body into ketosis, (which means the body primarily burns fat but not carbohydrates for energy) thus elevating the levels of ketones in the blood. Humans can use ketones as a source of energy for bodily functions and even as a replacement for glucose to provide fuel for the brain. However, ketones are toxic to the body if they are present in excess and the body actively attempts to rid itself of them. Ketones are removed from the body in the urine and also through the lungs causing a sweet-ish nail varnish like breath.

But, ketogenic food in excess is harmful. The side effects include dehydration, constipation, and occasionally kidney stones or gall stones. A very high level of ketones can be harmful to the body; it can be toxic making the blood more acidic which in turn can damage the kidneys and liver.

The authors of this study concluded - 'The undeniable and sudden effect of VLCKD on fat loss may be useful for those athletes who compete in sports based on weight class. We have demonstrated that using VLCKD for a relatively short time period (i.e. 30 days) can decrease body weight and body fat without negative effects on strength performance in high level athletes'.

Source:

http://www.jissn.com/content/pdf/1550-2783-9-34.pdf

Source-Medindia