Why the Marathon Can Be so Tough to Finish

Marathon Runner

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Marathon finishers wear their medal with pride. It is a badge of honor, a signal to the rest of the world that you are tough and made it through a grueling long-distance race.

As the story goes, the first marathoner, Pheidippides, who raced 150 miles from Athens to Sparta before the Battle of Marathon, declared "Nike!" (which translates as "Victory") and then dropped dead from exhaustion.

Even today, it's not rare to hear of people dying on the course. Whether you ran the whole course, did a run/walk technique or were a pure walker, you faced a supreme challenge. But what exactly makes the 26.2-mile marathon so tough?

Running on Empty and Hitting the Wall

The 26.2-mile marathon is a challenging running event because of its duration. After two hours of running (by the 20-mile mark for fast runners), the body runs out of carbohydrates and glycogen (sugar stored energy in the muscles,) and begins burning fat stores in the body for fuel. They call this "bonking" or "hitting the wall." The problem with fat burning for marathon runners is that it uses more oxygen which only depletes them of energy. If runners don't refuel with carbohydrates soon, they will bonk.

If you are doing a run/walk technique or purely walking the marathon, you probably won't experience bonking on the marathon. At a slower pace, the body uses fat stores for energy throughout the event and doesn't need to start burning up its own muscles instead.

You can prevent bonking by ensuring you have sufficiently carbohydrate loaded prior to the race. During the race, you can take in enough calories with energy snacks and carbohydrate-containing sports drinks to keep your energy stores from being completely drained. Walkers and run/walkers are likely to get progressively tired throughout the long-distance, but without the paralyzing experience of hitting the wall.

Getting Fluid Replacement Right Is a Marathon Challenge

Those who aren't careful to drink the right amount of water and electrolyte replacement drinks during the race will feel the effects of dehydration or hyponatremia (excessive hydration). The general recommendation is to drink when thirsty and use an electrolyte replacement drink at full strength throughout the marathon. This works well for the majority of racers. But for some individuals, factors such as age, medications, and certain health conditions put them at a higher risk for dehydration.

The recommendation is that during your marathon training you should weigh yourself before and after a long workout. If you are replacing fluids correctly, you should see no change in weight.

Slower racers who don't trust their thirst mechanism but instead drink at every stop can get into fluid overload. This can result in hyponatremia, a dangerous dilution of the electrolytes in your bloodstream that can result in serious illness or death.

Marathon courses generally provide drinks, but even large events have disasters where they run out of water or sports drink or can't keep up with the mass of runners. If you are one of the slower racers, you may encounter closed hydration stops, so it is wise to carry your own sports drink to have when needed.

More Marathon Hazards

The average marathon runner finishes the race in about 4.5 hours while the typical walker takes 6.5 to eight hours to finish. That is a long time to be out in the elements exerting yourself. Blisters and chafing, sunburn, and heat illness are common hazards. Muscle strains and sprains are more likely due to fatigue during the race.

By gradually building your mileage during several months of training, you will help toughen your feet and build the muscles, energy systems, and mental endurance you will need for the marathon.

After a marathon, the strain on the body is apparent. Marathoners get tiny tears in the muscles and there is a build-up of the toxic breakdown products from exercise—lactic acid, etc. You will need to expect a recovery period of at least a week with only light activity before getting back into your workout routines.

Caution: Marathons Are Addicting

But by being so tough, marathons also, in a way, become addictive. While some people can do "just one," and most vow never to do it again after their first, plenty of people get hooked on seeing if they can improve their times from year to year.

Hal Higdon, who has run over 100 marathons, writes in Marathon:, "In a marathon, you don't beat others. Instead, you achieve a personal victory." It is a very personal event, each participant having their own goal to achieve, often just to finish.

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