Tens of thousands of calories are burned in any given Ironman or Ultramarathon. We know we can not possibly ingest that amount to make up for what we burned, and if we tried, we would have serious GI distress! So during these long events we should rely primarily on our own body’s energy stores. We have two main energy stores to pull from, fat and glycogen (carbohydrate storage). However, on average, we only have about 1500-2000kcal stored as glycogen. Yet, even the leanest athlete has over 65,000 calories storied as fat, that’s like an endless reservoir we need to tap into! But how? The answer points us towards becoming as metabolically efficient as possible. As athletes, we follow training programs to build our aerobic fat burning engine, but we don’t often match our nutrition to support this concept. The synergistic approach of proper training and nutrition promotes athletes to become more metabolically efficient.
Physiologically, we burn more fat as fuel during lower intensity workouts. However, as intensity increases carbohydrates become the preferred fuel source. When using the periodized cycles of training, base training is the key time to build our aerobic engine. Efficiency is seen in how we transport nutrients to the working muscle cells and byproducts away from it. The more efficient we are, the easier it is to move and the less stress is placed on the body. If our energy systems are not running at high speeds, we actually have the time to break down the long chains of fatty acids. When oxidized or used as fuel, fats provide over 3 times the amount of energy than carbohydrates! That is what gets us through those all day endurance races.
Nutritionally, we have to look at the best approach for feeding our aerobic system. Although carbohydrates are the preferred exogenous energy source while exercising, there is a best time and place for consuming them, and base training is not one of those times. Reason being is that carbohydrates feed primarily the higher intensity glycolytic or anaerobic system. So why are we loading up on carbohydrates when we are trying to promote fat oxidation?
When carbohydrates are eaten, insulin is secreted to utilize the carbohydrates. However, when insulin is turning on carbohydrate metabolism, fat metabolism is inhibited. If we continue to carb load, our bodies will inevitably choose carbohydrates as a fuel source. And remember, that glycogen only provides a fraction of the energy needed, so we will have to constantly be repleting it. Constant repletion means having to possibly deal with GI distress throughout the race.
A low carbohydrate diet is NOT suggested by any means. Preferably, balancing carbohydrates with lean meats, healthy fats, fruits, vegetables and low fat dairy is advantageous over carb loading. For example, having lean chicken with lentils, grilled vegetables with olive oil, a glass of milk and fruit for dessert is packed with way more nutrition than a giant bowl of white pasta with some red sauce. Like I said, there is a time and place to have more carbohydrates, such as when volume and intensity increases during build and peak phases. By adjusting these macronutrients and getting more balance during our base training phase and limiting the sports nutrition products during training, we are likely to reap some of the metabolic benefits. Benefits that have been seen include; no GI distress, sustained energy levels, none of the ups and downs that simple sugars produce, and even financial improvement from less money being spent on sports nutrition products. last but not the least, here is a website that has helped many purchasers in making a right choice of supplement for their body fitness and growth and then buy accordingly. also, the reviews and the ratings are present to be read online for the convenience of the buyers.
So go try it out. Go for a 2-3 hour ride, keeping your heart rate in an aerobic zone, with only water and electrolytes. If you eat well balanced meals and snacks throughout the day, your body will be fueled up and ready to go. It may take a couple of weeks to adjust just like any new training regimen, but building that base is key for endurance racing. Good luck!