Here's What Running Marathons Does to Your Body

Woman running in the city

It seems like our Instagram and Facebook feeds are flooded with people who are either training for or who have just finished running a marathon. But we've got to hand it to them, especially since running 26.2 miles is definitely no easy feat. The marathon bandwagon also seems like a positive "trend" to jump on, since it gets your heart pounding, your muscles moving, and your blood flowing. However, running so many miles for such a consistent period of time has us wondering if there are any serious bodily dangers involved. To find out more, we turned to John Rowley, the best-selling author of The Positive Power of Fitness ($16), a certified trainer, and the ISSA director of wellness, to get to the bottom of it.

The Verdict

"While lots of running is a great way to build endurance, it does slow down your metabolism since you're technically losing muscle," Rowley says. In other words, running consistently depletes the calories needed for sustained muscle mass. Interestingly—we always assumed that running would give us Carrie Underwood legs. He also notes that running truly does cause a significant amount of wear and tear on joints because of the frequent and heavy impact. 

But that wear and tear may have something to do with the habits you've already cultivated. A recent study reviewing risk factors for runners found evidence suggesting a correlation between a history of previous injuries and a higher risk of receiving new ones from running. "Running is one of the most common sports that give rise to overuse injuries of the lower back and the leg," the study explains. However, acute injuries that have healed completely should not be cause for concern—only those with injuries that resulted in permanent damage are at high risk.

Surprisingly, the study also found that those who wear orthotics or other shoe inserts to aid in alignment could also face running injuries. Though this is a departure from the common belief that orthotics will help improve your stride, the findings conclude that using inserts could cause foot injuries if used incorrectly or if not prescribed by a podiatrist directly. In other words, don't purchase a drugstore insert before a race without consulting with a physician first.

On the upside, however, running still has a wide array of pros. Studies show that it is a natural antidepressant, increases muscle response, and can even extend your lifespan. The key here is moderation, though. 

The Solution

While you don't need to quit marathon-training cold turkey, there are several steps you should take to avoid injury. The first is to warm up: "Make sure you're moving around, loosening up your hips especially, and warming up your muscles and joints," Rowley says. He also urges all runners to stretch. "You're less likely to encounter injury while running if you've prepped your muscles with a good stretch." 

Next, he says it's important to be mindful of how you actually run the race. While you may be tempted to start off strong, Rowley says to work your way up gradually: "Instead of starting in a full-out sprint right on the starting line, give yourself some time to gain better range of motion and momentum—once you feel your body is acclimated to a comfortable speed, you can then start to push yourself a little more to avoid injury."

Research suggests that finding the sweet spot in your routine is also crucial. Adept runners who tend to run longer distances for longer periods of time are more likely to be injured due to overuse of muscles, while beginners need to be mindful of building stamina. "Running only once a week could lead to overuse injuries, especially in women," the study explains. "This is probably because running stresses the musculoskeletal system, which does not have time to adapt to this type of exercise because of the low frequency of running."

Lastly, Rowley recommends eating a diet full of lean protein and fresh greens, as well as plenty of water. As for the day before the race, he suggests eating a healthy serving of carbs, like a modest portion of pasta to give you energy for the big day. 

What Runners Have to Say

Laura Vollmer, a five-time marathon runner, says that the worst that's ever happened to her injury-wise has been black toenails (yikes!) and chaffing. However, she says that the reason she doesn't experience serious injury is because she trains properly: "Generally training for a marathon is three to four days of running (one of which is a longer run) and then two to three days of cross- and strength-training. Most often, the people I see get injured are those who don't keep up with workouts during the week and just do their long runs. From that, you see tons of injuries," Vollmer says. (To avoid those scary black toenails, and to make your runs as comfortable as possible, Rowley suggests changing out your sneakers every 300–450 miles.)

Evan Roth, a four-time marathon runner, adds that after one-and-a-half- to two-hour runs, there's definitely a lot of soreness and stiffness in his joints, but that they subside in a day or so. As a result, he stresses the importance of taking a day off, suggesting that many people get injuries when they forget to take a break every so often.

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Article Sources
Byrdie takes every opportunity to use high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial guidelines to learn more about how we keep our content accurate, reliable and trustworthy.
  1. Worp, Maarten P. Van Der, et al. Injuries in Runners; A Systematic Review on Risk Factors and Sex Differences. Plos One, vol. 10, no. 2, 2015, doi:10.1371/journal.pone.0114937

  2. Bjørnebekk, Astrid, et al. The Antidepressant Effect of Running Is Associated with Increased Hippocampal Cell Proliferation. The International Journal of Neuropsychopharmacology, vol. 8, no. 3, 2005, pp. 357–368., doi:10.1017/s1461145705005122

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