Enhancing fat metabolism for endurance and beyond

BY JULIE SEAMER
THURSDAY, SEPTEMBER 18, 2008

It is true. Exercise enhances fat metabolism. Yet most athletes' diets, whether they be gymnasts, runners or swimmers are focused on carbohydrates, not fat. Is this wise and if not, can fat help with performance?

If you have ever purposely pushed your body to its limits either in competition or recreation, chances are you increased your carbohydrate in the lead up or during the activity as a source of energy. This is a popular strategy for prolonging performance at high intensity over long periods but it actually isn't the only means of ensuring you don't fade. Beyond carbohydrate burning, endurance training also teaches the body to source a significant amount of energy from fat. This prolongs the endurance of muscle tissue, slowing the rate of glycogen depletion as to avoid "hitting a wall". The question many people ask is 'can this handy form of fat oxidation be achieved by nutritional manipulation and is it helpful'?

The answer is yes and no and the theory behind it is called fat adaptation. If a person consumes a high fat diet for 3-7 days before an event, followed by a high carbohydrate diet, during the high fat intake period the body increases the proportion of energy derived from fat and this effect is sustained for a few days (even when the diet is switched back to high carbohydrate). Once carbohydrates are again pumping through the body, muscle glycogen stores are replenished and the result is energy primed muscles with increased fat oxidation rate combining to prolong maximum output during an event. Quite impressive!

In fact, studies show that after a high-fat diet, the rate of fat oxidation is increased by almost 100% ¹. Other research has also proven that a controlled high-fat diet does enhance fat oxidation and even spares carbohydrate reserves ^2-3. This occurs because fat adaptation up-regulates enzymes involved in fat burning while at the same time down-regulating the enzymes responsible for carbohydrate burning.

While research is yet to prove that this mechanism truly enhances performance and there are some potential problems with periodically increasing intake of fatty foods (such as impacting on training ability by creating digestive discomfort) this process is interesting and worthy of further exploration. For now, fat adaptation reiterates the importance of fats in the diet, and the futility of cutting them out from your diet completely, particularly if active. The best types of fatty foods for everybody include oily fish, avocadoes and fresh nuts.

Aussie Bodies sponsor a wide range of athletes and teams who are living testimony to the value of quality nutrition though protein, on performance and beyond. However, for optimal metabolism, energy and well-being, and to complement adequate protein and carbohydrate intake, as demonstrated above, it is essential to supply you body with a healthy daily dose of good' fats; be it for daily life and/or sport. Recent scientific findings support the theory that good fats help fight fat, particularly fish oil and are the key component in disease prevention. The beneficial effects of fish oil on cardiovascular health, improving the integrity of all cell membranes, preventing inflammation of active joints and of the skin, and in reducing risk of metabolic syndromes such as diabetes and obesity are reason enough to incorporate healthy fats into your daily regime. If you end up faster or fitter than your competitors, that's a fringe benefit!

Healtheries Advanced Salmon Oil, Advanced Omega 3 and Musseltone with Omega 3 provide easily absorbed quality fish oil often lacking in most Australian's diets.

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