Fatigue and some muscle soreness are common at this point in the season--often due to increased aggregate mileage and training. But another frequent cause is inadequate nutrition, and several of you have asked how to ‘fuel up’ in order to minimize these effects.
Increases in weekly mileage as well as longer ‘long runs’ have our bodies craving additional fuel to support our increased activity (and consequent caloric burn). This will continue throughout the season. As fitness improves, our metabolism increases its ability to process additional nutrients. As endurance runners, our nutritional needs are different from the general public and even from athletes in power sports (such as weightlifting).
For runners, the best source of “stored fuel” results from a balanced diet throughout the week--not just by ‘carbo-loading’ the night before a long run. Maintaining a balanced source of carbohydrates, protein and fat, together with proper hydration (water and sports drinks for electrolyte replenishment) should be what every marathon runner strives to achieve.
Simply stated, the most efficient source of fuel in our bodies is glycogen. Through a chemical process, our bodies synthesize carbohydrates into glycogen, which primes and “feeds” our muscles when exercising.
Glycogen is stored primarily in our muscles and in our liver. Generally, we store enough glycogen to run about 20 miles. But a marathon is longer than that distance--so as we train, our bodies begin to compensate by learning to store and burn our fuel more efficiently. (This is the purpose of Long, Slow Distance Runs on the weekends as we discussed in Marathon Training Tip #2.)
For an endurance athlete, the dietary proportions should be approximately:
Carbohydrates: 55-65%
Protein: 20-30%
Fat: 15-25%
We can vary the percentages from week to week, but the highest source of caloric intake for endurance runners should come from carbohydrates. Fat and protein are essential building blocks as well, but in lesser proportions. Protein rebuilds muscles which are damaged while running and fat is a critical secondary source of fuel.
Several of you have asked how to manage hunger and fatigue on long runs -- recognizing that no matter how well we eat during the week, we still have ‘fuel needs’ immediately before and during on our long runs—and afterwards as well.
It is best to consume some food about 1.5 – 2.0 hours before a long run. Eating approximately 1.5 – 2.0 hours before a long run allows us to process our food and void our system before our long run. A few hundred calories will be sufficient (good examples - a small container of yogurt, a half bagel with some peanut butter or honey, or some fruit). Practice different combinations to see what suits you.
If you regularly drink coffee in the morning, it is ok to drink coffee before a training run, but take note of how you process coffee and allow enough time to ‘reprocess’ any coffee before the run.
During a long run, many runners use gel paks or blocks (‘gummy-like’ cubes); or ‘sport beans’ (jellybean-type products). Most of these products are primarily carbohydrate replenishment. The best time to use these products is before we expect our glycogen stores have been depleted, AND these should not be taken too early. If you are maintaining a well-balanced diet during the week, these products have little benefit until an hour to hour and a half into your run. However, different products affect our bodies differently. Practice using a gel pak or blocks or beans on a short weekday training run to be sure the product does not upset your stomach.
In addition to fueling with gel paks or blocks, sports drinks and water are important during a long run as well. Sports drinks contain electrolytes (sodium, potassium, zinc, magnesium, to name a few). When running long distances, it is common for runners to sweat a great deal, which flushes many electrolytes from our system. Many of you may have noticed a white residue on your face or body either during or after your run – this is salt (sodium) excreted during a run. Too much salt loss can result in fatigue and illness. Salt or electrolyte tablets can replenish a loss of sodium. Most sports drinks contain sodium as a primary ingredient.
Finally, gel blocks and paks should be taken with water. Do not mix these products with a sports drink at the same time. Water is the most efficient supplement to disperse the carbohydrates and minerals in gel paks and blocks throughout our system. Sports drinks are formulated to disperse their electrolytes and supplements efficiently. However, combining a gel pak (or block) with a sports drink overloads the system and has an adverse effect on the distribution of nutrients through our bodies. If you feel the need for both gel paks or blocks and a sports drink, alternate the two products throughout your run.
After a long run, there is a window of opportunity to replenish nutrients lost during a run. Our bodies will process carbohydrates and protein best when consumed within 30 minutes of ending the long run. Our bodies will continue to expedite the carbohydrate and protein reload for up to two hours after a long run, but the first 30 minutes are the most opportune time to replenish.
A favorite ‘post run’ recovery drink for many runners is chocolate milk—an excellent and healthful way to keep yourself ‘mooo-ving’ after your run.
Coach Brendan
“Good form will carry you through”®
