A marathon is a long-distance running event that spans 26.22 miles or 42.195 kilometers. Training for a marathon is more about a person's state of mind and willingness to work hard than anything else. A person needs to be prepared. One of the easiest ways to destroy your body is to push it past its limits. A marathon can be trained for, but even when a person takes twelve to twenty weeks training, they can still ruin a leg, tear something important, twist an ankle, what have you. A marathon is no joke, and most training regimes make the longest run twenty miles. It makes a person wonder, "Where do you get the last six miles for a marathon if the longest you run is twenty miles?" The answer is mental fortitude. This answer is also the reason the marathon can be so dangerous. Peak condition, adrenaline and a crowd of people cheering someone on are apparently enough to make up for six miles. Once a car runs out of gas, it does not matter what shape the car is in, the car will stop. The amazing thing about the human body is that it can be pushed past its limits, and even after passing said limits, it can often recover.
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Many marathon training regimes include a base mileage that grows over time. The person training for the marathon should run between three and five days a week, and increase their mileage a little at a time. The next thing regimes include is the long run, which should be done every week or so. The long run at its longest length is the aforementioned twenty miles. This also includes a building up of miles. Perhaps you run ten miles one week. In that case, you run eleven the following week. So on and so forth. Training plans also include methods to increase cardio capacity by doing things like tempo runs. The final and perhaps most important aspect of training is proper rest, which allows for recovery and rebuilding.

Tom Brough has run the Chicago Marathon three times. This is quite incredible and shows an intensity and love for the run. It would not be surprising to see him do it many more times.
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