Group Training: The Science Behind the Benefits

During the 1990’s, two professors decided to test out a radical, revolutionary treatment approach for losing weight. Hundreds of overweight subjects were given a diet and exercise program to follow, but only half were given the special treatment.


After 6 months, only 24 percent of the control group had lost weight, but 66 percent of the people receiving the treatment were successful! (1)


What was this amazing treatment?



Numerous studies have come to the same conclusions (1-3). Another study found that when people exercised alone, 43% ended up giving up and quitting their exercise routine. When people exercised with a companion, only 6.3% ended up quitting (3).


Epidemiologists have found that fitness spreads through social networks in a manner similar to a flu virus (4-7).


How is this possible?


In the early 1990’s, an anthropologist named Robert Dunbar began to notice an interesting phenomenon. Examining the brains of different primate species revealed that the size of the most advanced brain regions were correlated with the size of the primate’s tribe (8-10). The larger the tribe, the more developed the brain regions were that are responsible for controlling impulses. Based off of this finding, anthropologists theorized that our peers have a direct effect on our self-control.


Was this theory correct?


Many studies over the past few decades have supported this theory. Brain scans have demonstrated that merely telling subjects that they are being watched by others activates areas of the brain responsible for impulse control (11-12).


Even the illusion of being watched, such as pictures of eyes, is enough to cause people to litter less (13-16), steal less (17-18), wash their hands more (19), and assist others (20).


When we make a commitment to other people, we are exponentially more likely to follow through than when we make a commitment only to ourselves (21-37). For example, one study found that individuals who made their New Year’s resolutions public were ten times more likely to succeed than those who kept their resolutions to themselves (21).


In all types of endeavors, ranging from stuffing envelopes to quitting smoking to exercising, people try harder when they are in a group than when they are alone (38-46).


Conclusion:  Group Training Increases Self-Control and Causes People to Work Harder


The benefits of group training extend beyond the effects on self-control. Exercise responds best to group activities even better than other activities due to additional mechanisms. One study found that people who were exercising in a group experienced an increased endorphin production and twice as high of a pain threshold as people exercising alone (47).


Another study found that people who were being verbally encouraged by peers experienced increase muscle activation (48).


Conclusion: Group Training Allows People to Push Themselves Closer to their Physical Limits


Not only do people work harder while in groups, but they enjoy it more as well. According to research, experiences that are boring or difficult but experienced with others are later remembered to be more enjoyable than experiences that are easy or exciting but completed in isolation (51).


Conclusion: Group Training is More Fun


Unfortunately, many individuals are hesitant to invest the time and energy into an exercise routine because they are worried that they will ultimately fail and have wasted their time. When obstacles arise, this lack of confidence can lead these people to give up. Not surprisingly, much research has found that this confidence is a major factor in who ultimately is able to stick to an exercise regimen (60-66) and lose weight (67).


One of the best ways to improve confidence is to train in a group. When we see our friends and family succeed, we become more confident that we too can be successful (53-59), and this confidence allows us to push ourselves harder and persevere in the face of obstacles.


Conclusion: Group Training Boosts Confidence and Perseverance


Another important benefit of group training is the affordability of working with a coach. Research has shown that compare to those who exercise alone, subjects who work with a coach lose more fat, build more muscle, gain more strength, improve endurance more, and are more likely to prevent injury (68-74).


Group training makes working with a  coach dramatically more affordable. For example, rather than one client paying $80/hour, there may be eight clients paying $10/hour. This way, clients can still gain access to much-needed coaching at affordable rates.


Conclusion: Group Training is More Affordable


Next time you try to lose weight or improve your fitness, don’t do it alone. Finding one or more like-minded individuals with similar goals to train with may be one of the most important steps you can take towards improving your results and making progress towards your goals.




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