Ironman Coeur d Alene 2006: Training Diary

This is a rough guide on nutritional data in the real world. No marketing, no data from company funded research to obtain skewed data.
No academic dishonestly.
Company scientists tend to believe "theory" without obtaining repeatable data, and present flawed results of research publishing only the data they with, to benefit the marketing of a product. I have researched the literature for over 15 years on this subject and understand the total confusion by many athletes.
Many single articles will be mass marketed to consumers, even though the data is flawed, and the techniques to obtain the data lack the basic understanding of science and research. I find it amazing that scientists with MS and PhD degrees would put such a lack of thought into research protocols.
Many PhD candidates will publish research that is missing critical control arms and unfortunately, a company will capitilize on the flawed data to sell a product. Protein supplementation into maltodextrin solutions during moderately intense exercise is an example.

I will try to keep this very simple as to what works for me.
I have used these techniques since running competitive marathons in 1990-2003, then extrapolated to my first Ironman race at CDA in 2004, and have used with minor variations for the past 15 years.
Keep it simple...there is no magic bullet.

2 Major Sources of Energy: Carbohydrates (sources liver, muscle, blood), Fats

Glucose is high energy souce of calories. Stored as Glycogen (long chains of glucose molecules) in the Liver and Muscle. Free-floating Blood Glucose is an additional source in prolonged exercise. The average amount of glycogen stored in liver and muscle supplies about 2 hours of glucose. After that, the primary source of blood glucose used for energy must come from supplementation. Additonally, supplementing glucose early in exercise and raising blood glucose levels will slow the rate of depletion of glycogen from liver and muscle, thus further prolonging the 2 hour window of storage.

Fats are always used as an energy source, in the background of the primary limiting agent, Glucose. Fats are high yield energy calories, but are slowly utilized during exercise. You do acquire about 50% of your calories from fat. That is not enough to fuel performance. Fats are generated in a background of aerobic systems. Once you run out of carbohydrates (sugars), your body then must rely on Fat primarily, and protein secondarily as sources of all energy. The only problem is that the physiologic systems required to metabolize fat are well below those required to sustain exercise levels above 50% cardiac max. This is the primary reason for "bonking". You have to slow down to utilize fat as your primary energy source.

Protein is a minimal energy source, contrary to what the mass marketing of product lines lead us to believe. I recently emailed the product scientist of a major sports supplement, the company of which states in their pamphlets that your body uses 15% of calories from protein after 3 hours of exercise. Subsequently, if you dont provide that 15% in your drink, your body will "break down its own muscle" to provide the protein needed. This is one of the most elementary, uneducated statements I have ever heard in my 18 years of post-high school education. I asked for the specific research articles that demonstrate this and of course no response. This demonstrates the heavy bias that major companies have, and the degree of academic dishonesty companies will go to in order to sell their products. The new Power Bar Nutrition CD ROM I received in the mail has specific recommendations on nutrition during the race, and is narrarated by Lance Armstrong...its not suprising to me that there is NO mention of adding protein to your supplement while racing. Only high carbohydrate. Of course, Power Bar is not trying to sell a protein drink to athletes for racing, while other companies are.

Protein can be converted to glucose, which is then used for sustainable energy. This primarily occurs when your body results to fat as its primary energy source. As long as blood glucose levels are sustained, protein contributes very little calories to the overall energy pool during exercise. Studies on Tour de France cyclists have shown that even in those extreme conditions, protein needs of 1.5 gram/kg body weight/day were easily met with a normal supplemented diet. I will discuss this in paragraphs to follow. There are numerous article demonstrating a more than adequate protein pool for long, intense exercise, as long as the daily protein requirements are met. Additionally, the use for protein as a significant energy source during exercise is far out-weighed by blood glucose levels. Keep blood glucose levels elevated, and the need to convert protein to glucose in negligible.