The Science Behind Marathon Training

Woman on treadmill to determine her aerobic fitness.

The Science Behind Marathon Training

Metabolic Cart in action in the Signature Health and Wellness Clinic in the University of Minnesota Health Clinics and Surgery Center.


Nearly 10,000 runners surge through the streets of Minneapolis, Minnesota. Some run the 26.2 miles to Saint Paul for the first time, others are veterans. The roar at the starting line is deafening. In the midst of the commotion and clamor nearly two dozen men and women pepper the course around them, focused. They are not runners, nor part of the crowd. 

This is the Twin Cities in Motion Marathon Administrative Medical Team: 20 health care providers behind all medical aspects of the big race. William Roberts, M.D., M.S., professor in Department of Family Medicine and Community Health in the UMN Medical School, has been a familiar face in that crowd since 1982, spending the vast majority of those years in the medical director role. 

“I like taking care of runners, I like all the enthusiasm.” Roberts said it’s what keeps him coming back year after year. “I enjoy the group of people I work with on the medical team and I like the group of people administering the race. Over the years you get to know people well.” 

358 Days of Preparation

Three hundred and fifty-eight days. That’s about how long it takes to prepare for the Twin Cities Marathon from a medical professional standpoint. The team of about 20 health care providers and volunteers have to carefully plan for every scenario, and that means starting preparations for 2018’s race October of 2017. Their preparations and their reactions can potentially make the difference between life and death. 

Video Extra: Measuring Physical Exertion

Measuring Physical Exertion

“Running a marathon isn’t really a fitness activity. It’s beyond fitness,” Roberts explained. “It takes some forethought and training to get to that level.”

Running a marathon isn’t really a fitness activity. It’s beyond fitness. - William Roberts, M.D.

 The team is meticulous; a lot of thought goes into what they set up and where along the course. Several cots are placed at the finish line, as well as a tent which can be heated as well as cooled. Supplies are ordered: such as IV’s, blankets to warm people, tubs and ice water, and towels. Automatic external defibrillators (AEDs) are strategically placed along the course, some given to bike teams riding along with the runners. Ambulances line the route. Everything and everyone has a purpose: to react in an emergency.

A Calculated Journey

A group of medical providers volunteer at the Twin Cities MarathonGroup of volunteer UMN faculty, fellows, and residents at the Twin Cities Marathon.

As a family medicine physician specializing in sports medicine, Roberts knows the importance of training for an event as demanding as the Twin Cities Marathon.  He has seen the consequences of a runners’ lack of preparation first hand.

Roberts has witnessed heart attacks on the course; seven total, with only two fatal. This makes for an 80% survival rate, which Roberts attributes to the quick actions of readily available personnel. Without a plan or medical staff like this literally waiting on the sidelines, Roberts believes a typical survival rate would be 5%.

“We are set up to respond quickly,” Roberts states.

Another ailment Roberts and his team see on the course is exercise induced hyponatremia, which happens when runners drink too much water. The sodium in a person’s body is diluted, a potentially very dangerous situation. 

“We’re prepared to treat hyponatremia, but it’s best not to drink too much fluid along the course,” said Roberts.

Training the mind along with body

Chris Lundstrom, Ph.D., M Health, UMN CEHD helps a runner determine her aerobic fitness.Chris Lundstrom, Ph.D., M Health, UMN CEHD helps a runner determine her aerobic fitness.

Whether or not a runner becomes ill or dangerously fatigued during a marathon is often within their control. Preventing that is part of training, which has just as much to do with education and knowledge as it does with physical activity. Sometimes it’s as simple as knowing your personal limits.

Over the years, they have found the people who suffer from heat stroke during the race are often the ones who have been ill a week or two prior to the marathon.

“I encourage people not to run the race just because they trained for it, but because they feel well and ready to go the distance,” said Roberts. He suggests asking yourself questions like, what can you tolerate in terms of heat? Are you feeling well, or not? 

If you don’t feel right during the race, think about why that might be. Is your heart working well? Are you thinking clearly? Are you sweating okay? Are you taking in the right amount of fluid?

“It’s easy to get swept up in things and take off too fast. It’s exciting. You’ve got nearly 10,000 people surging through,” said Roberts. “It’s easy to take off too fast, or get caught up in the excitement.”

This year in particular, Roberts is especially worried about the weather and how it could affect unprepared runners.

“If we get that rogue hot day it could be a problem for us because it has been so cool this fall,” said Roberts. Basically, a hot day could keep the medical team very busy on race day.

People who train in cooler weather will not be acclimated to warmer weather come race day. Activity in the heat gets allows your body adjust to and tolerate warmer temperatures. You sweat a larger volume, and you don’t put as much sodium out in your sweat, therefore you can tolerate higher temperatures at a given work load. If you don’t have that constant heat exposure, that acclimation goes away, and it goes away pretty fast.

There are ways to acclimate yourself regardless of the weather outside.  One trick is to wear more clothes or work out in a heated space.

The changing marathon culture

Dr. William Roberts poses with Robert Johnson, M.D., another faculty member in the Department of Family Medicine who has competed in every Twin Cities MarathonWilliam Roberts, M.D., UMN Medical School with Rob Johnson, MD UMN, Family Medicine, who has competed in every race.

In 1982, there weren’t nearly as many people participating in marathons as are there are now but they were noticeably faster as a whole. The peak of the race would hit at about 3 hours into the marathon. Now, it’s closer to 4 ½, 5 hours before the peak

One theory for why the runners group seems to be slowing has to do with who is participating in marathons now. There are a lot of people who put the marathon on their bucket list, others who were athletes in high school, perhaps found running to be an easy way to stay fit, and set the goal of completing a marathon as a way to stay motivated. Christopher Lundstrom, Ph.D., Department of Kinesiology in the UMN College of Education and Human Development, teaches a marathon training class, and says he sees people from all walks of life in his classroom. Most have some running experience but it's not necessarily competitive. 

“The first year, 8 years ago, we had about 40 students, and now every year it’s over twice that,” said Lundstrom.

Lundstrom’s class informs runners why they are training the way they are. “With knowing a little about the science behind training an individual can leave the class better prepared to do it on their own and make smart decisions,’ explained Lundstrom.

A lesson to take with you

Lundstrom’s class will go through the whole gambit of training, including different types of work outs to do. The real value is in the deeper look, for example explaining what runners can expect from doing a long run versus doing a high intensity interval session or proper nutrition for fueling muscles. Marathon classes like Lundstrom’s treat training for marathon as a life style choice. 

“I always say the body doesn’t care if its Saturday night or Monday morning. Whatever you’re doing to yourself impacts your ability to recover and to train,” said Lundstrom.

Recovery is a big part of training, and everyone is a little different. Some people might recover fairly quickly from a long run but be tired out for a few days from a more vigorous, shorter workout. And there are other people who are the exact opposite. 

“A lot of that is just getting to know your own physiology, your body and how you respond,” stated Lundstrom. “Many people try to do too much too soon. They have to take a step back.”

The science behind training

A woman wearing a V02 mask to measure her oxygen intake while running.The mask worn to measure a runners' cardio-respiratory fitness.

At first glance, the room looks relatively normal. Located on the 5th floor of the University of Minnesota Health Clinics and Surgery Center, it’s pretty sparsely decorated with only a treadmill, stationary bike, scale, and computer on a standing desk. After some cursory questions and measurements, it’s time to get on the treadmill. Dr. Lundstrom reaches under the desk and pulls out a long thin tube, which is attached to the computer. He clips a cloth and plastic mask to the other side, which you place over your mouth and secure behind your head. It’s time to begin.

As a Fitness Development Coach for the University of Minnesota Signature Health and Wellness Program, Lundstrom measures VO2max, which is a measure of the amount of oxygen you are able to utilize at a given time, and he uses this technology to do so.    

“It’s basically a gold standard for measuring cardio-respiratory fitness,” said Lundstrom.

As the person runs, the computer is sent data. Lundstrom processes that information and then interprets it for the patient. It can have an effect on how often they exercise, at what intensity, and their recovery, among other things.

The results are important for endurance athletes but also for the general population when it comes to uncovering cardiovascular disease risk. The higher a person’s VO2max, the better their aerobic capacity, and therefore the less likely they are to have cardiovascular disease down the road. These are all good things to keep in mind when training.

Risks vs benefits

It’s widely documented that being physically active can reduce the risk of cardiovascular disease. An event like a marathon can add an extra level of motivation to get moving. It often gives people a goal to prepare for and be consistent for. Both Roberts and Lundstrom agree that while it is never too late to get involved in marathons, those starting later in life, and with less experience do need to prepare even more diligently and smarter.

 “Certainly the more novice you are, the greater risk you have for injury,” said Lundstrom. 

It’s basically a gold standard for measuring cardio respiratory fitness. - Christopher Lundstrom, Ph.D.

For a heathy person who has been physically active for a lifetime and not had any health problems, ramping up to a marathon might not be a big deal.

“For someone who has spent numerous years partaking in high risk health behaviors, it’s best to connect with your doctor before training,” advises Roberts, “The sins of the past aren’t easily forgiven from a health perspective.”

This doesn’t mean if you’re not active you shouldn’t become active. It simply drives home the importance of a healthy lifestyle, the need to know your body and health history before you start training for a marathon.

Hard work will pay off

There’s no denying training for a marathon is a lot of work. There’s data showing people who don’t prepare well enough and don’t get enough mileage under their belts beforehand have more markers of tissue damage than those who are more prepared.

“It isn’t a Sunday walk. It’s a challenge,” said Roberts.

But with education, dedication and a little science on your side, it’s possible to accomplish in a safe and healthy way. And what’s more, it’s doctor recommended.