As a coach, I tend towards obsessing over the workout details and my first love has always been the physiology behind those details. The workout planning and details are what initially drew my to coaching. However, in a team environment, these details matter little unless everyone buys in and stays motivated to pursue the end goal to their fullest extent.

If you are a part of the University of Houston Cross-Country team you have to sit through a couple presentations a year where I ramble on about some scientific concept that intrigues me at the moment. I like to make the athletes part of the process so that they understand why they are doing what they are doing. If you were a part of the team this year, you would have heard about this study…a lot! It wasn’t about training, peaking, muscle fiber types, or any other related physiology related topic. Instead it was about the realm of science often left for psychologist, sport or otherwise, called motivation.

It turns out that motivation can function almost like a disease. It is contagious and can work its way through your peer group in the same way that the flu potentially can. To coaches, teachers, or anyone who deals with motivating groups of students this shouldn’t sound too surprising. In sports, we refer to this as “team culture.”

The surprising thing is how contagious it is.

An interesting study published by the National Bureau of Economic Research used cadets entering the Air Force Academy as a way to tackle the question of whether exercise habits/performance was contagious. The Air Force Academy allows for a unique way to study the issue as cadets do a standard fitness test before entering the Academy and then at regular intervals throughout. Additionally, they are assigned into peer groups for their duration of their stay at the Academy. What we are left with is a nice easy way to study how fitness changes throughout their 4 year commitment and whether the fitness of those around them affected the entire squadron.

The researchers therefore tracked almost 3,500 freshman for 4 years to see how peers who were the least fit coming out of high school impacted their entire squadrons fitness.

What they found was very surprising:

They initially showed that the level of fitness during HS of your peers had a very large effect on your own fitness. In fact, they found that your peers HS fitness had a bigger impact on your own fitness than your own initial fitness coming into the Academy!

“it suggests that the effect of friends’ high school fitness on own current fitness is nearly 40 percent as strong as the effect of own high school fitness”

Knowing the large impact that peers seemed to have on others in their groups fitness trends, they then set out to determine whether it was the most fit people pulling the group up or the least fit people dragging the group down. As they pointed out in the article, it’s easy to imagine a situation where you have an incredibly fit person who is passionate about getting in their workouts and following their training plan so that it encourages others to do the same. Similarly, it’s easy to imagine a situation where the least fit person slacks off and skips workouts and starts impacting those around them.

What they set out to discover was what group mattered the most.

Contrary to what most would think, it was the least fit friends who tended to play a large impact on reducing fitness and causing friends to fail the fitness tests.

As the authors put it:

“The estimates imply that if half of your friends were to become among the least fit for reasons unrelated to you,  your own fitness level would drop by nearly 20 percent of a standard deviation and you would be nearly 60 percent more likely to fail the fitness requirement.  Put differently, the effect of the least fit peers on college fitness is 85 percent of the effect of one’s own high school fitness. Even more strikingly, the effect of the least fit peers on the probability of failing the fitness exam is larger than the effect of own high school fitness.”

The findings are pretty profound in that fitness seems to be contagious and that it is the least fit person who has the greatest impact.

So what?
As I like to point out to me team, what this means is that everyone matters. You aren’t simply affecting your own fitness, but that of everyone around you. Your decisions to exercise, be motivated, bring a positive attitude to training, and so forth can impact everyone.

Secondly, in life we tend to focus on the high performers. We focus on the stars of our program and sometimes neglect the less talented athletes. Hopefully, beyond the ethics of it, you can see that we likely have this backwards in terms of motivation. It appears to be the least fit who might have the greatest impact. In graduate school, former Texans and Redskins General Manager Charlie Casserly taught one of my classes on leadership in sports. He explained his rule that it was the bottom 20% that swayed the team culture. If they were on board, things went smoothly, if not, they were the ones who would cause problems.

Tying this back to team sports and cross-country in particular, it shows why your group dynamics matter so much. In the aforementioned research, it clearly showed that fitness is contagious. To me, it’s simple. Who you surround yourself with in your peer group or team matters a lot.

While this study focused on motivation contagion in regards to fitness, other research has demonstrated (largely using the Framingham study) that things like obesity, smoking, depression, and even self-control all can be similarly contagious.

Knowing this, it all boils down to two take away messages:

1. Every single person in the group counts.

2. Choose your peer group and inner circle wisely!

link to study

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    1. George Beinhorn on November 7, 2014 at 5:24 pm

      This was very interesting. Several long-term, well-document case studies of major sports teams reveal that everything you've said is true. The documentation is in the books by and about Bill Walsh, whose ideas on sports cultures set the standard for successful NFL teams since the early 1980s; Phil Jackson, whose "11 Rings" is a wonderful inside look at the positive cultures he built with the Bulls and Lakers; and finally (although there are many more examples), Tara VanDerveer's wonderful account of her year as coach of the USA women's basketball team before the 1996 Olympics. Among the many inspiring articles on positive sports cultures, an ESPN online article by Alyssa Groenigk stands out: "Lotus Pose on Two," on Pete Carroll's highly experimental and wildly successful transformation of the Seattle Seahawks.

      It was a defining feature of Bill Walsh's tenure with the 49ers that he insisted on helping every player to succeed at his own level, including the players he inherited from the previous year's woeful 2-14 team. (Randy Cross called it "the worst 2-14 team in the history of the NFL"). Walsh got rid of whiners and complainers. Nor did he confine his campaign to instill positive attitudes to include only the players an coaches – he even schooled the ticket sellers to be positive and upbeat, because he knew that every person's attitude would contribute to the team winning a Super Bowl (which they did, in just three years).

      There are sound physiological reasons why positive thoughts, feelings, and attitudes contribute to sports success. For example, in my book The Joyful Athlete, I present research by the HeartMath Foundation that clearly shows that expansive attitudes of kindness, compassion, etc. enable the heart to perform much more efficiently at all training intensities – a huge advantage for elite runners and other athletes. Every runner has likely experienced this: how the best training is accompanied by positive, harmonious feelings. And it's not just the efficient body that stimulates those feelings; it's a closed-loop process, where deliberately cultivating those feelings influences the body as well.

      It was a pleasure to read your article. It's been a fundamental tenet of great running coaches that the individual athlete counts – including Bill Bowerman, Arthur Lydiard, among others. By the way, an excellent account of the positive spirit among Lydiard's runners can be found in Keith Livingstone's fine book, Healthy Intelligent Training – The Proven Principles of Arthur Lydiard ( Many thanks for an enjoyable read and deeply thought-provoking ideas.

    2. […] contagion: Running with others to boost your morale and fitness.  A question though: What motivates you more? A running group or new gear to try […]

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