We’re all familiar with the idea that germs and diseases can be contagious. It makes perfect sense that if our family or social circle has people who are sick that our chances of getting sick if we are around them increases. It doesn’t mean we automatically get sick, thanks to the strength of our immune system, but the likelihood goes up.

It turns out that germs aren’t the only thing that are contagious. Research is now pointing to the fact that social concepts are contagious too. Just like the stomach bug can be passed around your family or team, the desire to workout, stop smoking, lose weight, gain weight, or really have any self control is all contagious.

Establishing Contagion

In one of the bigger long term tracking studies called the Framingham study, subjects have been tracked on a variety of health related topics and social structures for decades. By analyzing the data, they could look at how health changed in social groups.

The surprising finding by Christakis and Fowler (2007) was that if health changed within your social group, it increased the likelihood of you experiencing that same change. For example, they found that if a person had a friend who becomes obese, there own chance of being obese increased by 40%, and if one spouse became obese their chance increased by 37%. In other words, obesity seemed to spread like a disease within your social group.

That’s just one long term study though, what other evidence is there? It turns out that researchers have found a wide range of behaviors that can spread like a germ would, including alcohol consumption, smoking, sleep loss, drug use, depression, and even rule breaking. What they’ve found is that goals, whether good or bad, are contagious, and thus why in the research it’s referred to as goal contagion.

So if you have a temptation to lose weight, if others around you are resisting temptations to lose weight, then it reinforces that behavior and you are more likely to stay with that goal. However, on the other hand if your goal is to lose weight, and you see a friend indulge in cake for example, you’re more likely to give in and indulge in that cake too.

Perhaps the most interesting of those studies was one on the spreading of the goal of casual sex. Researchers set up a study where they had participants read an article about a man seeking to pick up women. Then they had a random women or man interrupt the experiment. The male participants were much more likely to help out the women who interrupted than the man IF they had read the article beforehand. And the reason why was because the participants felt like helping the women slightly increased their chances of “hooking up”. So simply reading and believing that others had the goal of casual sex, increased the partipants want/need/goal of finding it too.  So sex is contagious…

While we won’t explore those implications for obvious reasons, let’s take a look and see how this applies to exercise.

A 2010 study by Carrell et al. tracked fitness in the Air Force using the standard fitness tests that cadets take before entering and then periodically throughout. Similar to running, it provides a standardized test that you can track and see. They tried to see what would predict fitness for individuals as they progressed in their career. Surprisngly, it wasn’t
their initial fitness before joining, but instead was the fitness level of the LEAST FIT individual in their squadron. There was a regression to the mean essentially, where all of the fitness regressed towards the least fit member.

The impact of this research is pretty profound and should be easily transferrable to the world of running or team sports. It means that in our team environment, that we can potentially have athletes dragging us down.  But how does this happen?

The Spreading of Self Control and rule breaking:

While this shouldn’t be too much of a surprise that social context influences behavior, the degree of spread is. We all like to think that we are individuals with strong wills and desires, but the reality is we have a brain built for a primitive world that has built in roundabout ways to withstand those natural temptations. So, like in my blog post, self control and willpower play a role. Add in a dash of motivation and not unlike how battling fatigue works we have our own inner battle of resisting temptation versus giving in. With our ‘primitive’ self wanting to give in to temptation and instant gratification and our higher level brain processes telling us to resist so that we can keep on track for accomplishing our long term goal.

So what happens when we see other people give in to temptations is that it tells our brain that it’s okay to break the rules. Essentially, it allows our brain to justify instant gratification. On the other hand, if we see someone resisting temptation, then it reinforces our goals and long term self-control mechanisms. In an article entitled “The spreading of disorder” in Science, Kees Keizer explains what is called the“broken windows theory” which states that if there are signs of rule breaking, people are more likely to continue to break the rules. Or in other words, if there are broken windows present, more people will commit petty crimes like breaking windows. To back up this theory, research has been done that putting trash on the ground makes people more likely to leave their trash
places, and locking bikes in spots that clearly say “No bikes” leads to more
people leaving their bikes there too. They concluded that:

“We found that, when people observe that others violated a certain social norm or legitimate rule, they are more likely to violate other norms or rules, which causes disorder to spread.”

What does this have to do with sport? Social norms , whether good or bad can influence your behavior. So if you see athletes on time to practice, getting in their mileage, etc. then other teammates are more likely to do the same. But it goes beyond seeing and witnessing, it’s the BELIEF that they are getting things done.

It’s why bad practices, even by the “worst” athlete can slowly spread throughout the team.  Similarly, in the world of pro sport, drug abuse can spread along these lines. The belief that more people are doing drugs likely leads to more athletes doing performance enhancing drugs. And since research shows that there is a high belief of athletes doing PEDS at the elite level, it’s a scary thought to think that those attitudes are encouraging PED use.

Based on this research we are left with the concept that seeing and/or believing that something is a social norm, encourages people to fall in line with that norm. The important part is that these social norms can be for good or bad, it’s up to you and your peers!

The Brain’s surprising role:

In the world of brain research, one of the more interesting findings in the relatively recent past was the discovery of mirror neurons. Mirror neurons are neurons in the brain that essentially mimic things we see. Without getting too complicated, if we see someone go through pain, like a friend burning their hand on the stove, the mirror neurons in our brain fire so that we understand and almost empathize with that person. So in this case, the pattern for pain actually fires.

Another, someone surprising finding is that these neurons fire even if we’re simply watching someone on TV or in a movie performing an action. For example, one study by Wagner et al. (2011) found that smokers who watched a movie with someone smoking had areas in the brain activate that were in charge of moving the hand. Why would this happen?

The brain was prepping for the person to move their hand to get a cigarette and start smoking. So just the act of watching someone smoke decreases the likelihood of a smoker resisting  a cigarette because the brain is essentially pre-trained to get ready to start that action. What all of this means is that if we see someone having a reward, our reward area minimally gets activated, which primes the pump and gives us that longing for a reward. So if we see someone endulging in that chocolate cake, our reward area is getting prepped to activate to a degree. Which in turn creates a want for that reward, that hit of dopamine that comes with wanting a reward.

In essence, it makes it really freaking hard to have self-control.

So what?

What we are left with is a curious case of other people influencing our pursuit of goals. In one way it’s our brain responding to their actions and in the other it’s social influence spreading our way.

To end with I’ll leave you with a study presented in Stanford psychologist Kelly McGonical’s book that looked at social change. In this study, researchers looked at environmental change in a California neighborhood. They surveyed the households and found that changing for the environment was one of the highest reasons a person would change. Then they put hangers on a group of houses to encourage changes to energy use behavior. They had 4 different hangers that focused on the following topics:

  •  Promoting environmental change
  •  Conserving energy would help the future
  •  The changes will lower bills
  • 99% of the people in your community reported turning off lights to save energy

They then went through the subjects electricity bills and energy use to see what flyers had an impact. The only one that showed in change in usage was the 99% of the people are doingit. Or in other words, everyone else is doing it so you should. Social pressure works.

The point is that goals, attitudes, and self control are contagious. If simply reading about some guy trying to hook up with girls, increases our want for doing the same, then how much influence do you think those who surround you have on your life? The simple thing is to surround yourself with people of similar goals and values, but the flip side of the coin is that you can be a bastion of change yourself. Having good habits and setting examples can spread and you can be the start of that in your group or team.





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    1. Kelly on May 19, 2014 at 4:04 pm

      So what determines the direction of the influence. Example: one spouse eats well, exercises, loses weight and gets fit. The other one eats for comfort, doesn't exercize, and gets obese. Is it just the one who sticks to their guns the longest?

      Also, what happens when a hard working and discplined person is added to a laxed and easy going team. How can we know if the new addition will influence the team, or if the team will "ruin" the new addition?

      Is it simply persistence?

    2. Robert Osfield on May 20, 2014 at 2:45 pm

      I noticed that this group effect in pacing in marathons and ultra-marathons. Almost everyone knows that it's best to start out easy, but almost everybody gets carried along with adrenalin and the fact that everyone else is storming off at a what will turn out to be an unsustainable pace. The same group effect is noticeable at the end of races where everyone starts slowing and it's only a tiny minority that are able and willing to continue pushing on at the end.

      I have begun pacing using a HR monitor in my ultra's which governs my pace in way that is independent of group influences, my splits through the race are far more even and am able to finish strongly with a lower RPE even at the finish despite my higher finishing pace. The differences between the pace one should run at and the pace that a mass of people run at brought starkly into focus when you find hundreds of running charging past in the first miles of race, but then overtake them all and more over the next fifty.

      I'm pretty sure that seeing others start off fast encourages oneself to start fast, and also when other start slowing and walking it becomes a signal that it's OK and normal to give in to fatigue and start slowing and walking. Having official pacers in a race will likely help alleviate some of this problem, holding runners back at the start and providing a template that it's OK to keep pushing. Although I suspect near the end it's more your peers in the pace group that influence each others rather than the pacer. It be interesting to see if marathoner with pacers throughout the race make a difference to how much of positive split on average one sees in the race. If this group effect does influence pacing then I would expect paced marathon to see on average less pronounced average positive split.

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