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Frequent Trail Runner contributor and renowned running coach, Jason Karp, PhD., shares his top tips for beginner racers and those looking to move up from 10K to the marathon.

Photo by Glen Delman

Wear the Right Shoes

You wouldn’t go to a business meeting in sandals, or to a cocktail party in Nikes, would you? Regardless of how fast (or slow) you are, trail shoes will improve your trail-race experience by providing better traction and protection from rocks. A word of caution: race day is not the best time to switch over to minimalist or “barefoot” trail shoes. Without developing the requisite foot and leg strength, you would be hobbling to the finish line.

Master the Hills

Big or small, hills are inevitable at trail races, so learn to love `em. Drive yourself uphill with an exaggerated arm swing, forward lean from the ankles and strong push off from the ball of your foot. Since hills force you to work harder, steady your effort level rather than worrying about speed. Also, don’t hesitate to walk if running is overly taxing.

On downhills, shorten your stride and quicken your cadence. When gravity is tugging you downhill, you have less time to plan foot placements, so look ahead a few steps to anticipate trail obstacles.

Mind the Descent

Even though running uphill feels harder, downhills cause more problems. Its gravity-induced eccentric muscle contractions, during which muscle fibers are forced to lengthen, cause microscopic tears and high-impact breaking forces bring a greater risk of injury. Damaging muscle fibers, however, makes them stronger, protecting them from future damage. While you can expect sore muscles at first, the more you run downhill, the less soreness you’ll experience.

Up the Ante—Transition from 10K to the Marathon

Running philosopher George Sheehan once said, “The marathon is an adventure into the limits of the self, a theater for heroism, where the runner can do deeds of daring and greatness.” Nearly half a million people will complete a marathon in the U.S. this year, and often traverse less-trodden paths and give new meaning to Frost’s road not taken.

Before taking on one of the trail marathons in the 2011 Trail Runner Trophy Series, consider these important tips.

Fuel Right

Unlike in a 10K, in a marathon, your muscles become depleted of stored carbohydrate (glycogen). After around two hours of sustained running at a moderate intensity, the muscles are depleted and your blood sugar takes a dangerous dip, leaving you feeling like you, well, just smacked into the proverbial wall. The lesson here is learning to eat on the run. One of the easiest ways to top up glycogen stores and avoid “hitting the wall” is by eating one or two energy gels or drinking an energy drink per hour of running. Experiment with different brands, flavors and amounts in training.

Be Water Wary

Another issue than can affect marathon performance is dehydration, which decreases blood-plasma volume and compromises oxygen flow to muscles, causing you to slow down. Contracting muscles produce heat, so long-distance running increases body temperature, a condition called hyperthermia. This decreases blood flow to active muscles and sends more blood to the skin to cool you down, which forces your pace to slow. Mind your hydration right from the start. Carry two small bottles and take small sips every five to 10 minutes, alternating plain water from one and a electrolyte/carbohydrate mix from the other.

Run a Lot

Beginner marathoners should build to a minimum weekly mileage of 30 to 35 miles because to run a longer race, you must simply train more. Running lots of miles improves blood vessels’ oxygen-carrying capability by increasing the number of red blood cells and hemoglobin, stimulates the storage of more fuel (glycogen) in the muscles, increases the use of intramuscular fat to spare glycogen, creates a greater capillary network for a more rapid diffusion of oxygen into the muscles and increases your muscles’ aerobic capacity.

Run Long

A primary focus of marathon over 10K training is the inclusion of long runs. Do most of your long runs on trails to condition your body to run on uneven terrain. As a guideline, your long run should not exceed about 30 percent of your weekly mileage, though this rule may be broken if you run only a few times per week. The pace should be comfortable enough that you can converse with your partner. Lengthen the distance by one mile per week for three or four weeks before cutting back by a quarter to a third of the distance in a recovery week. Continue adding miles in this manner until you reach 22 to 24 (or about 3 to 3½ hours, whichever comes first). Your longest run should take place two to three weeks before your marathon.

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