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The Stress of a Marathon

The Last Six Miles are Worse than the first Twenty

You hear a lot of stories about people who have just completed their first marathon: People hitting the "wall" during the race. Runners having to go down stairs backwards after they've finished. Runners having to walk much of the last 6 miles of the marathon. These stories all concern the high stress and negative effects of a marathon, and the stories are true for many marathoners.

A Personal Example

Let me give a personal example to illustrate that there is a lot of stress connected with a marathon. I ran my first marathon after I had been running for eight years. Even though I was only running about 45 miles per week before that first marathon, I was pretty fast for a recreational runner who didn't train for speed. My speed came as a result of my doing a lot of miles during those eight years. I ran a weekly 15-mile long run year around at a comfortable pace of 7 minute miles. In fact I could run up to 18 miles at that pace. I was 46 when I ran my first marathon.

As I neared my marathon, I realized that I had only run 20 miles one time as my longest training run and that I would probably slow down as I went past that point. I decided that I would run the marathon at an 8:30 pace, because I thought that by slowing down a minute and a half, I would have a margin of energy that would carry me through to the finish. So, I started the marathon at an 8:30 pace. This was in 1981, and timing chips and GPS watches hadn't been invented. I did have a stop watch, but my watch didn't time laps. So, I resorted to the high-tech solution of writing on my hand my times for various miles, and as I passed each mile marker, I would look at my hand and adjust my pace accordingly. As a result, I maintained my 8:30 pace for 18 miles.

Then it happened. At 20 miles, I stopped running. I had run into the infamous "wall" and had run out of energy. I didn't experience any pain. I just stopped running and started walking. I walked/jogged the next six miles to the finish.

My paces illustrate the stress and negative effect of the marathon and were as follows.

Distance Pace
Miles 1-18 8:30
Mile 20-26 Walking & Jogging
Average Pace 9:00

I could run 18 miles at a 7 minute pace and did run it at a 8:30 pace. At 20 miles I was reduced to walking/jogging. I finished the marathon with a 9 minute pace. Such is the stress of the marathon. I was well trained for 18 miles but poorly trained for greater distances.

The good news is that I didn't experience any pain before or after the marathon, and I never had to go down stairs backwards. In fact, I was back on the roads two days later. On the first day of running after the race, I only went half a mile before my body said, "That's enough!". By the end of the first week I was up to a mile and a half, and by the end the first month, I was back to my normal training. All without injury or pain.

My experience illustrates both the good and the bad of a marathon. Let's look at the marathon and understand why it has such high stress, and then let's look at ways that we can overcome that stress and have a great experience in our first marathon.

The Wall

As explained in Wikipedia,

Carbohydrates that a person eats are converted by the liver and muscles into glycogen for storage. Glycogen burns quickly to provide quick energy. Runners can store about 8 MJ or 2,000 kcal worth of glycogen in their bodies, enough for about 30 km or 20 miles of running.

When I reached 20 miles and was reduced to running, I had exhausted my supply of glycogen, and my body started to burn fat for energy. This depletion of energy is probably the most significant cause of marathon stress.

Other Sources of Stress

The distance of the marathon, 26 miles 385 yards, is another significant source of stress. Many beginners aren't used to walking or running distances more than a few hundred feet. They struggle to develop the muscular and aerobic strength to go longer distances. During a marathon, their feet will pound the road about 69,000 times, and each step shocks their body with a force that is about 2.5 times their body-weight. That is a lot of stress on their body!

Another source of stress during the marathon that many runners don't understand is water -- either too much or too little. Too much water means the runner's body salts are diluted, and this can cause serious problems, including death. Too little water means the runners become dehydrated, and this means their body temperature will rise, possibly leading to heat exhaustion or heat stroke. This problem is complex since it is affected by the climatic conditions during the race and by the characteristics of the body of each runner.

Yet another source of stress that is controversial but, I believe, does exist, is improper training for the marathon. Many runners enter a marathon without being prepared for the negative effects of the stress, and their lack of training compounds the effects of the stress. There are many training plans that are published in books and on the Internet to guide people in their training. These plans vary in their characteristics such as number of weeks encompassed by the plans, the length of the runs specified by the plans, the intensity of the runs, and the amount of rest specified by the plans.

Finally, a significant source of stress is the public conception of the marathon as a grueling time of pain, sweat, and suffering. A runner told me that "I just assumed that [pain] was part of the package."

Ok, What do We Do?

The stress of a marathon can be minimized, so let's look at ways of reducing the stress.

Avoiding the Wall

Runners hit the wall when the glycogen stored in their cells is depleted. Thus, the obvious solution to this problem is to store more glycogen in their cells. If the cells can hold 2700 calories instead of 2000 calories, the marathon will end before the glycogen is exhausted. Think of the wall as an object. By storing at least 2700 calories in the cells, the runner has pushed the wall out beyond the end of the race and thus never hits the wall. A runner can do this by training over distances that approach the length of the marathon. The runner can also consume energy snacks and gels during the marathon to supplement the energy in the cells. The training runs of distances greater than 20 miles must occur a number of times since our bodies are slow to adapt to new conditions.

Developing Greater Muscular and Aerobic Strength

There is only one way to develop muscular and aerobic strength. The runner must stress the muscles and aerobic system, which will cause damage to the body cells, and then rest while the body repairs the cell damage and becomes stronger. If the runner wants to develop strength to run 15 miles, the runner must run distances that approach 15 miles. If the runner wants to develop the endurance to run 26 miles, the runner must run distances that approach 26 miles. These training runs don't have to be fast. In fact, endurance is best developed by the running of Long Slow Distance or LSD.

The good news is that these training runs also cause your body to develop the ability to provide the oxygen necessary for the marathon. Running a marathon should be an aerobic activity in which your body gets sufficient oxygen during the race.

Running a marathon is this simple. You train for the marathon distance, and you repeat that training until you no longer hit the wall and you no longer suffer from the impact of stress on your muscular and aerobic systems.

Getting the Right Amount of Water

Runners have a problem knowing how much water to drink, because the amount varies with the climatic conditions and with individual body characteristics. The hotter the day, the more a runner sweats, and the more water is needed to replace the sweat. The more a runner sweats, the more body salts are lost, and the more a runner needs to replace those salts. Here are a few guidelines.

bulletDrink when you are thirsty. Your body knows when it needs water, and it tells you via thirst.
bulletDrink enough liquid to replace your sweat. The color of your urine at the end of a run is a good indicator of this. It's ok to have a slight color to your urine, but you should not have a dark color.
bulletThere are sports drinks and gel packs that provide body salts that can be consumed during the marathon. I like gel packs, because they provide energy and body salts, and the particular gel pack I use provides enzymes, antioxidants,  and vitamins. I need about 10 oz of water with each pack, and I take a pack every hour. Thus, I need at least 10 oz of water every hour. However, I sweat a lot so I drink additional water according to my thirst.
bulletExperiment with liquids during your training runs to determine how much liquid and which liquids you should use. The marathon is not the time for experimentation.

Proper Training

This topic has already been discussed, because all of the things mentioned above as ways of overcoming the stress of marathons are part of proper training. I would, however, like to address training plans, because I believe that many beginners choose the wrong plan for their training.

Published training plans seem to be organized into two groups: those that train you to complete a marathon but not to overcome the stress of the race, and those that train you to complete a marathon and to overcome the stress. You can usually tell which group a plan you are considering belongs to by looking at the number of weeks encompassed by the plan and the length and and number of the long runs.

Many marathon plans commonly require 16 - 20 weeks for the training, and they frequently have you do only one 16 to 20-mile long run. These plans are, in my judgment, adequate to train you to complete a marathon, but they are not adequate to train you to handle the stress of the race. Persons following these plans are the ones who suffer pain during and after the race. The plans seem to be geared to younger runners who may have the strength to complete a marathon with minimal training.

A few plans require more weeks for completion and have you run multiple runs greater than 20 miles. These plans have, I believe, the potential to adequately train you to handle the stress of marathons, because they train you over the marathon distance for a long enough period of time, that you begin to adjust to the marathon distance.

Even after you've completed your marathon plan, I believe that you may not be ready to run your marathon. I believe that a person shouldn't run a marathon without at least a year of training to develop the muscular and aerobic strength that will be needed during the race and to push the wall past the marathon distance. In my case, I ran for about eight years before I ran my first marathon, and I had no problems other than hitting the wall during the race. To me, it was a very enjoyable and rewarding experience. My next marathon, three months later was the same way, and my next two marathons a year later were a continuation of my enjoyment of marathons. I didn't have the time to train over distances longer than one 20-miler per marathon, so I never did push the wall out past 20 miles, but when I hit the wall, I walk/jogged to the finish with no pain during or after the run. I'm not suggesting that you spend eight years preparing for your marathon, but I am suggesting that you spend at least a year, a year after you've developed a base of about 24 miles/week and have started your marathon training.

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