Marathons test runners’ health and endurance. When preparing for a marathon, athletes eat healthy foods, regularly run long distances, and give their bodies adequate rest.
However, a recent study published in the American Journal of Kidney Diseases found that running a marathon can damage a runner’s body. Scientists found that two out of three runners showed signs of kidney damage after running these exceptionally long races. In most cases, marathoners’ kidneys recovered within a few days of a race. However, scientists are concerned that marathon running might present health dangers to those who already have weak kidneys, such as people with diabetes or high blood pressure, or for people who are elderly.
A Job for the Kidneys
The organs known as kidneys serve vital functions in the human body. People have two kidneys, each of which is about the size of a fist. Kidneys are found on either side of the spine, low inside the rib cage. The kidneys’ main responsibility is to remove waste products from our blood. In a typical day, kidneys filter and return the equivalent of about 200 quarts of fluid from our bloodstream.
However, running a marathon is not a typical day. Scientists say that the enormous effort needed to finish these races floods the bloodstream with chemicals that help the body run so far. Unfortunately, the fluids which aid long-distance running also strain the kidneys. Marathon running can cause other health issues, as well. For example, since the body is devoting so much energy to moving, it provides less energy to the immune system. As a result, it is not unusual for runners to have colds or fevers after completing these long races.
Marathon runners also experience measurable physical changes. The race cause a temporary loss of fluid between the vertebrae in the spine, so runners may finish the event slightly shorter than when they started. Changes in weight are common, too. Marathon runners can lose anywhere from five to ten pounds of bodily fluids during their run.
Fortunately, the study found that marathoners’ kidneys were not permanently damaged and that they were typically back to normal within a few days. Even so, researchers are concerned about the signs of kidney damage that seem to peak one day after these long runs.
Doctors think that the overall health benefits of training for a marathon are greater than these ill effects. However, researchers caution that there is a higher risk to the bodies of people who attempt a marathon without proper training.
With this in mind, effective marathon training programs start with short runs, only gradually adding longer and longer distances. Many people are rising to the challenge—in 2015, 509,000 people completed marathons in the United States. In comparison, in 1990, 224,000 people, half as many, finished U.S. marathons.
Marathon is the name of a town in Greece. In 490 B.C.E., the Greeks won an important battle there against the Persian army. The Persian army had invaded Greece. At the Battle of Marathon, however, although they were greatly outnumbered, the Greek fighters were able to defeat the larger Persian army.
A legend tells of a Greek messenger named Pheidippides who was sent from Marathon to the Assembly in the Greek capital of Athens to announce the victory. Pheidippides, the story goes, was so focused on delivering his message that he ran the entire distance from Marathon to Athens without stopping. Historians disagree on how long Pheidippides’s legendary run was, since he could have taken several possible routes. Most estimates, however, place the distance somewhere between 20 and 25 miles. All of the estimates, though, are very close to the standard length of a contemporary marathon: 26.2 miles.
Marathons became popular in the United States early in the twentieth century. The 1908 Summer Olympics in London, England, included a marathon won by an Italian runner named Dorando Pietri. The length of this race, 26 miles and 385 yards, would eventually became the standard length for marathons.
In the crowd was Sir Arthur Conan Doyle, the creator of the famous fictional detective Sherlock Holmes. Conan Doyle, already a famous writer, was asked by the British newspaper the Daily Mail to report on the event. Without television or radio, fans instead had the benefit of Conan Doyle’s suspenseful prose.
“Good Heavens, he has fainted; is it possible that even at this last moment the prize may slip through his fingers? Every eye slides round to that dark archway. No second man has yet appeared,” Conan Doyle reported. “Thank God, he is on his feet again—the little red legs going incoherently, but drumming hard, driven by a supreme will.”
Pietri was the first to cross the finish line. Although he was awarded the gold medal, the judges soon ruled that he had won unfairly because he had received assistance reaching the finish line. With Pietri disqualified, the gold medal was instead awarded to the second place runner, the American Johnny Hayes. With this controversy and Hayes’s surprising victory, Marathon Mania soon spread across the United States, eventually moving on to Canada and Europe.
At the peak of Marathon Mania, runners were booked into arenas and stadiums to race for excited fans. In December 1909, after he lost his Olympic gold medal, Pietri raced against British runner C. W. Gardiner at the Royal Albert Hall in London. While contemporary marathons are typically run on large outdoor courses, these two runners instead competed on a 90-yard-long track. Gardiner won, completing the 524 required laps in a little over two and half hours.
Marathon Mania died down not too longer after these races. However, the idea of a long-distance running race as a measure of athletic ability remained popular in the U.S., and continues to remain popular today.
So, Is Running Really Dangerous?
While scientists think that marathon running can strain the kidneys and other parts of the body, doctors generally agree that running is good for your health, with the right preparation.
In a 2014 study, scientists found that people that who run as little as 50 minutes a week can add about three years to their lifespans. However, developing good habits in running or other exercise is vital.
“Exercise may be the most important component of a healthy lifestyle,” cardiologist James O’Keefe wrote in the British journal Heart in 2012, “But like any powerful drug you’ve got to get the dose right.”
If you want to start running or any form of exercise, The Mayo Clinic offers these tips.
- Assess: People can become discouraged or even injure their bodies if they attempt too much exercise too quickly. To avoid this problem, see what your current level of fitness is. Time how long it takes you to walk one mile, see how many pushups you can do, or measure how far you can stretch. A doctor or school nurse can help you evaluate your current level of fitness.
- Design a Program: It is easier to exercise with a goal in mind, such as preparing for a 5K race or trying out for a sports team. It is important to start slowly and only increase the amount of exercise gradually over time. Find something that you can easily do each day. Be sure to allow your body enough time to rest between workouts.
- The Right Equipment: Beginning to exercise does not require expensive equipment, but whatever you wear or use should be safe and in good condition. Be sure that your shoes fit well and you wear clothes that allow your body to move freely. Keep in mind that there is not one type of sneaker: some are great for certain sports but not others. A physical education teacher or clerk at an athletic shoe store can answer your questions.
- Start!: Always warm up with stretches and simple exercises before attempting anything too strenuous. If you find a 30-minute daily run is too difficult, break it into three ten-minute sessions. Do not follow the traditional advice, “No pain, no gain.” Symptoms like pain, shortness of breath, dizziness, or nausea, is your body telling you that you are attempting too much too soon.
- Keep a Record: After you’ve been exercising regularly for six weeks, revisit some of the activities you did in step one, to re-assess your fitness. You may be surprised to discover that you can more easily do some exercises you had difficulty doing only a few short weeks ago!
Learn about more ways to stay active at the President’s Council on Physical Fitness and Sports.
Images and Sources
Johnny Hayes Photo: Kid33
Johnny Hayes Photo License: Public Domain