Fat, even more than carbs, is a terribly misunderstood nutrient. Often maligned by dieters and fitness “experts,” fat is generally labelled as something to avoid. But, confusingly, fat is still considered a vital nutrient by health authorities. So why do we need to eat fat? What role does it play in the human body? Specifically, how can runners benefit from the right amount of fat?
The Confusion
Part of the problem when it comes to discussing fat is that there’s a big difference between dietary fat, that marbles your steak, and bodily fat, which is more correctly called adipose tissue.
The bane of the exercisers existence, adipose tissue is created by the body to store excess calories. The interesting part is that your body doesn’t care whether these calories come from carbs, protein or fat; If you don’t immediately need the energy, then, it becomes adipose tissue for later use.
This confusion has led to many health-conscious individuals going on low-fat diets in an effort to cut back their bodily fat. A problem arises, however, when these same people continue to eat excess calories and thus gain weight anyway.
So when discussing fat, it’s important to understand that the fat you eat does not go immediately to your hips. In fact, along with carbohydrates, fat is a main source of energy for your body. As an athlete, the energy provided by fat can make all the difference in your performance levels during both training and competition.
But, this doesn’t give you license to chow down on bacon during your training season. Not all fats are created equal, though, so it’s vital that you understand which fats to avoid and which can actually improve your health.
The Line-Up
Unfortunately for all the carnivores out there, the so-called unhealthy fats are generally found in meats. These are called saturated fats and have been linked to an increased risk of heart disease and type 2 diabetes. Another unhealthy fat, trans fat, is also found in some meats but is generally artificially produced by partially hydrogenating the otherwise healthy unsaturated fats. Both saturated and trans fats a usually solid at room temperature and include such delicious things as shortening and butter.
The healthy fats, as mentioned above, are those of the unsaturated variety. Further divided into mono- and poly-unsaturated forms, these fats have actually been shown to lowers cholesterol, decrease the risk of heart disease and diabetes and even help improve body composition. These healthy fats are found in fish, nuts, avocado, olive oil and many vegetable oils.
Fatty Fuels
Throughout the day, your body burns a mixture of carbs and fat for fuel. The exact ratio, though, is adjusted based on the availability of fuel, as well as the length and duration of your activity.
During short, intense burst of activity, carbs are the primary fuel. But, since your body can only store limited amounts, your reserves will run out relatively quickly. Fat, however, is the backup fuel once carbs are no longer an option. A diet rich in healthy fats could, therefore, help to improve your performance during endurance events.
A series of studies conducted in South Africa experimented with this theory and found that a high-fat diet greatly increased the endurance of cyclists. Surprisingly, the subjects were able to perform the task for twice as long after eating a high-fat diet.
The Balance
While these findings may seem to suggest that you should load up on fat before your next race, it is much more complicated than that. A high-fat diet can interfere with the necessary role that carbohydrates play in your body, decreasing your performance at high intensities. The key is to eat a balanced diet, consisting of about 20% healthy fats. Under the direction of an experienced trainer, you may wish you experiment with some fat-loading before an event but this should be done with caution.
Have you tried fat-loading for a race? Please share your experience in the comments.
Sources
http://www.active.com/running/Articles/The-New-Rules-of-Marathon-Nutrition-Fat?page=2
http://www.mayoclinic.com/health/fat/NU00262
