By Charles Poliquin
Increase your body’s use of fat for energy during training to lose fat and improve your performance. You don’t need supplements with inventive marketing—there are no magic bullets to fat loss. There are research supported methods of shifting the body to call on fat for fuel rather than carbs.
In a recent study, researchers used what is called a “fat adaptation” diet and had well-trained endurance athletes consume a high-fat, low-carb diet for 2 weeks in conjunction with normal training. The athletes were able to increase the rate at which the body burned fat. The athletes went back to a high-carbohydrate diet to restore muscle glycogen stores, and even then, the metabolic changes favoring the use of fat for fuel persisted.
In this case the fat adaptation period was made up of 70 percent fat, 15 percent carbs, and 15 percent protein. To carb load, trainees just flip flopped the carb and fat percentages to 70 percent carbs and 15 percent fat for three days, although researchers suggest that only one day of high carb eating is necessary to restore muscle glycogen in endurance athletes.
Will the benefit will extend to strength trainees and power athletes? It will! Research suggests that “fat adaptation” can work for trained, untrained, endurance, and power athletes, but that some people seem to be non-responders, regardless of exercise mode. Non-responders were those who didn’t benefit from improved performance due to the “fat adaptation,” although they were able to enhance fat oxidation.
The point is that due to different genotypes, individual trainees may need varying ratios of carbs, fat and protein for optimal fat loss and performance. For some, a strict 20-gram a day carb model in the form of green vegetables will produce best results, while others may be able to actually devote a small percentage of calories to a greater variety carbs.
In addition, a new study using juice from the cashew fruit, called cashew apple juice, identify key nutrients that can enhance fat burning. Researchers found that giving both trained and untrained men cashew apple juice for 4 weeks significantly increased fat burning and decreased the use of carbohydrates for energy during 20 minutes of intense exercise.
Since cashew apple juice is not readily available or affordable in the U.S., researchers point to the key nutrients in the cashew apple that increase the body’s use of fat for fuel:
• Cashew apple juice is very high in vitamin C, which enhances the production of two enzymes required for the biosynthesis of carnitine, which has a rate limiting effect on fat oxidation. When either carnitine or the enzymes necessary to process it run out, fat burning in the body stops.
• The amino acid leucine is provided in high quantities in cashew apple juice, and leucine “tells” the body to use fat for energy and spare glycogen during exercise. You’ve probably heard of leucine because it’s the most powerful of the branched-chain amino acids (BCAAs) that can aid in muscle building and optimal body composition.
• Anacardic acids are unique to cashew apple juice and have been shown to decrease body fat deposits in the rat liver. They may also play a component in enhancing fat use. Anacardic acid may also be present in mango, although this hasn’t been confirmed with research.
Yeo, W., et al. Fat Adaptation in Well-Trained Athletes: Effects on Cell Metabolism. Applied Physiology, Nutrition, and Metabolism. 2011. 36, 12-22.
Prasertsri, P., t al. Cashew Apple Juice Supplementation Enhanced Fat Utilization During High-Intensity Exercise in Trained and Untrained Men. Journal of the International Society of Sports Nutrition. 2012. 10(13).