I’ve been a personal trainer and strength coach now for almost 10 years. It’s an incredibly interesting thing to me to see how people react differently to the same exact plan.

I’m not referring to physiological reactions to strength training programs or to changes in body composition with weight loss programs. I’m talking about behaviors, how people respond to instructions that are meant to help them with their goals.

Why does one person fail to follow instructions while another person follows them and succeeds? Even more pressing, why do people pick decisions that are counterproductive to their goals? Individual differences in behavior fascinate me. So much so that I’ve spent the good portion of the last 4 years divulging into the topic.

There are plenty of scattered theoretical answers to this. It is my hope that in my attempt to articulate what I consider important individual differences, you can change your behavior or find your motivation to reach your goals.

I’m a coach, my expertise is first and foremost in exercise and exercise behavior and secondly in weight loss. My formal education is in exercise science, but I’ve spent much more time studying behavioral psychology and actually coaching people.

While some of this information is highly specific to these topics it can be applied to most areas of life. Let’s start out with two schools of thought.


B.F. Skinner is the originator of operant condition; the idea that behavior is determined by consequences, rewards, and punishments. This paints a picture of behavior as reactive to the environment.

It’s logical and works well when studying rats who don’t enjoy being shocked. Rats (and humans too) withdraw ourselves from negative situations and move towards rewarding situations. But to me, this feels absent of freedom of choice.

On the exact opposite spectrum, behavior is seen as self-determined and autonomous. That is, we have the freedom to do what we enjoy doing. We also may engage in behavior that is congruent with our life values even if it’s not pleasant or initially rewarding. Behaving for external rewards or to avoid punishments is seen as controlled, the opposite of self-determined.

To me, this generates a spectrum; behavior that is solely reactive and automatic on one end and behavior that is goal driven, mindful and self-determined on the other. Reactive behavior is not inherently bad unless the environment is set up to make reactive behavior damaging (i.e. obesity).

Unfortunately, in terms of achievement reactive is usually not good. What is easy generally lacks value and what is challenging is often valuable. If we let our health be reactive, that is, incomplete response to the environment we would be or be on the path towards becoming diseased. I would make the argument that most people let their health behaviors be reactive.

For example, under 5% of the United States population exercises sufficiently maintain a healthy diet and refrains from smoking and drinking in excess (taking 10 years off a person’s life).

If we accept the challenge we would in a sense, flourish in our health. It’s a relatively universal concept; what is worth having doesn’t come easy. What is easy is reactive. So, what drives us to be autonomous and mindful of our behavior?


In the most elegant and simple explanation I have heard, people engage in behaviors that they have the opportunity to do, have the capabilities to do, and have the motivation to do.

Self-efficacy, a person’s confidence in their ability for a given task is a major determinant of behavior. If we don’t think we can do it, we won’t do it.

Opportunity is an interesting concept. Speaking frankly, devoid of physical or mental limitations we all have the opportunity to do anything we want. For some people, it is easy. If you grew up with unlimited resources being healthy shouldn’t be a problem. If you are economically disadvantaged, it will be harder.

But we all run our own race. With absolute certainty, efforts should be made to reduce disparities. That being said, blaming the environment or upbringing for your problem(s) robs you of responsibility for your actions.

Change is futile unless a person takes full responsibility for their behavior. Motivation is all the cognitive/mental energies that drive behavior. Opportunity and capability will both influence motivation. We’re not motivated to do things we lack clear opportunities for and we aren’t motivated for things we feel we lack the capabilities for.

Taking a look at motives can help you understand motivation. The question, “can I do it?” covers capability and opportunities but “why do I do it?” covers motives. Why would I change isn’t exactly at the forefront of most people’s minds.

Your motive (your why) will influence whether or not you persist in the face of obstacles.

A person who values their health as part of their identity will overcome obstacles with more perceived ease than people with vanity (i.e. look jacked, lose weight) goals. Those people who exercise or attempt to lose weight based on extrinsic rewards (praise) or in the avoidance of negative feelings (not happy with themselves) may fare worse than people who have the same goal but do it for different reasons.

On an interrelated note, a person who goes to a facility to exercise because they feel a sense of community and relatedness will enjoy the process more than someone who goes to a commercial gym and plugs their headphones in.

In conclusion for this section, we all the have the opportunity to achieve our health goals. For some people, it might be more challenging than for others, but we need to place responsibility on the individual while recognizing and overcoming challenges.

We all have the capability to learn how to find forms of exercise we are good at and we all have the capability to find ways to eat healthy. Lastly, while people may have vanity focuses for health behavior change they should also find activities they love or connect their change with their health which everyone to some extent values. If your goals are more on the controlled end, find a facility that helps you build your confidence that also has a strong sense of community.


Motivation is a prerequisite to change. However, once the change process begins people need what is called self-regulation skills. One of the best self-regulation techniques, that is predictive of success is self-monitoring.

A person needs to (1) form a plan and (2) monitor behavior and (3) evaluate the outcomes of the plan in terms of success and adherence.

A specific form of planning, called implementation intentions links behaviors with daily situations. For example, “when I am done with work I will go to the gym for 30 minutes to do my resistance training routine”.

This form of planning makes behaviors more automatic and allows for some flexibility in the occurrence of the behavior. For example, if you said you were going to exercise at 5:30 but then worked until 7:00, what do you do? By saying “when I leave work” you allow for the behavior to occur despite some unplanned deviations in your schedule.

I make my online clients do this every single day (in person clients are given this too). They then report back adherence. This is monitoring behavior. The self-monitoring of behavior after the formation of a plan is a good way to practice mindfulness. By doing this, behaviors exit the realm of the automatic and environmentally reactive and move into the realm of self-determined.

After a certain period, adherence and outcomes need to be evaluated. If outcomes are not what is desired with full adherence the plan needs to change but if outcomes are not what is expected with less than full adherence, environmental restructuring, motivational interviewing, or plan restructuring needs to be addressed.

In the end, the responsibility for behavioral adherence needs to be placed on the individual while also identifying and addressing challenges that may arise. In an ideal world, goals would be self-determined, that is related to individual values and enjoyment. People should enter into environments that foster confidence and promote healthy behaviors through strong community. Behavior needs to become more mindful and specific individually tailored plans need to be made.

Trainer/Author Bio:

Justin has been a certified personal trainer since 2009. He holds a masters degree and in exercise science and is currently pursuing his doctoral degree in health and exercise sciences.

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