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Running with Heart: How the Body Handles a Marathon



On May 6, 2017, the running world had its collective gaze fixed on a Formula One race track in the town of Monza, Italy. As the cool, overcast day began, three athletes set out to do something that no runner had ever achieved in the history of the sport – complete a marathon in under 2 hours. For the uninitiated, this goal requires running 26.2 miles at a pace of 4 minutes, 34 seconds per mile. And while no runner had ever completed a marathon in under 2:02.57 (2 hours, 2 minutes, 57 seconds), there was plenty of optimism that a sub-two-hour marathon was possible.

Every aspect of the event had been meticulously scrutinized and controlled by Nike, the event’s sponsor and organizer. A team of scientists at the Nike Sports Research Laboratory crunched every number to predict the perfect course, weather, and conditions that would be needed to shock the running world. The team had even gone so far as to create a new type of running shoe, custom fit to each runner’s foot, featuring a carbon fiber midsole to give the athletes every advantage in this race against the clock. However, as the miles added up, and two of the three runners dropped out, it would be 32-year old Eliud Kipchoge of Kenya to cross the finish line in an incredible, but ultimately short of goal time, 2:00:25.

While the vast majority of human beings will never attempt to run a sub-2-hour marathon, the event provided valuable insight for all runners looking to conquer the distance. This event wasn’t focused on who would win; rather, it was focused on every variable that can affect marathon performance. Protecting the world class runners and their bodies from less than ideal temperatures, wind gusts, elevation changes, and inadequate shoes was paramount to success. To produce perfect results, it would require perfect athletes, and perhaps more importantly, perfect environmental factors. So what does this mean for the other 99 percent of runners?

On Monday, April 16, 2018, I’ll be competing in the 122nd running of the Boston Marathon. This will be my fourth marathon, and while my goal time of 2 hours, 54 minutes, is far from attempting to break 2 hours in the marathon, the nature of my training is very similar to that which guided the elites running at Monza.

Preparing for Boston – let alone any long distance event – can require weeks if not months of training. For me, this has included waking up before dawn to get in runs that can vary from 8-20 miles. At times the training can be grueling, like running on a 20-degree December night. At other times, the training was something I just needed to get out of the way, like a rain-soaked 5-miler on Super Bowl Sunday. This work hasn’t just been to ensure a faster finish time; it’s also been crucial in establishing the cardiovascular conditioning necessary to overcome the physical challenges of the distance.

Much has been made of the effects of marathon running on the heart. A 2012 study found that, “long-term excessive endurance exercise may induce pathologic structural remodeling of the heart and large arteries.” Does this mean the marathon is dangerous?

Not necessarily says, Neel Chokshi, MD, an assistant professor of Clinical Cardiovascular Medicine, and medical director of the Penn Sports Cardiology and Fitness Program. In a 2017 article, Chokshi contextualizes these warnings saying, “While evidence suggests an increased risk of cardiac events during high intensity exercise, the overall likelihood of such events is ultimately very, very low. There is far more research to support running and exercise as a benefit to heart health, rather than a detriment.”

So if running a marathon can be done in a relatively safe way, what are the types of things an athlete can do to improve their body’s ability to perform? One answer is more sleep. It’s no secret that a lack of sleep can effect mental acuity, but it can also have a large impact on physical performance and endurance. Brian Sennett, MD, chief of Sports Medicine, emphasizes the importance of getting eight hours of sleep before and after the marathon so the body can perform and recover properly.

Sennett is also very clear on hydration. He suggests grabbing fruit and sports drinks, noting to the Philadelphia Inquirer, “building back up your nutrition and hydration is also important.” At this point in my running career, I’ve participated in over 20 half marathons and three marathons. I can say that without a doubt, my best races have been those in which I was properly hydrated, and the exact opposite can be said of those times I skipped the water stations. The need for hydration, preferably in the form of 50 percent water, 50 percent Gatorade, cannot be overstated. A 2005 article from Runner’s World recommended runners consume 13.5 to 27 fluid ounces per hour during a marathon.

No matter what kind of shape an athlete is, or how much sleep or hydration they bring to the race, Mother Nature often has the last word when it comes to performance. In the 2007 study, Impact of weather on marathon-running performance, researchers found that as weather increases from about 41 degrees to 77 degrees, marathon performance decreases. This decrease is even more pronounced for those running at a slower pace, who will inevitably spend more time on the course. As temperatures increase, the need for good hydration becomes more and more critical. A 2011 study in the Journal of Athletic Training found, “dehydration during strenuous physical activity, particularly in warm or hot environments, can increase the risk of heat exhaustion, heat stroke, and muscle cramping.”

In my experience, the only way to overcome problematic weather is to change expectations. If there’s a 20 mph head wind, understand that it’ll take about 20 percent more energy to run the same pace. If there’s a pouring rain, make sure to keep a steadier footing. Outside of indoor tracks and on the treadmill, running rarely takes place under controlled conditions, and athletes need to be aware of this.

Knowing all of this – how important conditioning, sleep, hydration, and respect for the weather can be – there’s only one thing left: race day. Whether a runner is chasing a personal record, a top five finish, or just trying to mark another achievement in their life, there are always nerves and some level of anxiety going into an event. Perhaps Kathrine Switzer, the first registered female participant in the Boston Marathon put it best: “All you need is the courage to believe in yourself and put one foot in front of the other.”

That, and maybe a world class sports science program.

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