American Fitness Magazine Behavior Change

Force of Habit: How Behavior Change Science Impacts Success

Shirley Archer, JD, MA
Shirley Archer, JD, MA
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afm_fall2017_coverOriginally published in the fall 2017 issue of American Fitness Magazine

Personal trainers know successful training programs require time, progression and individualization. Yet trainers often have clients who just don't achieve their goals-they fail to lose weight or they give up after a few months-despite nutrition and fitness programming grounded solidly in science. Given our dedication to empowering our clients to make positive life changes, this can be disappointing or even maddening. Why does this keep happening?

The answer lies in the science of behavior change. Significant research findings show that behavior change strategies are essential to helping people adopt the habits required to reach health and fitness goals and to improve life quality.

It's not enough for a client to decide to lose 25 pounds or to sign up for training three times per week. Each individual requires specific support. For example, a client may need to learn what foods to eat and what triggers him to overeat. She may need help mastering the best exercises and discovering how to avoid making excuses for not training.

The bottom line is that even when people say they want to be healthier, they need specific reinforcement to overcome counterproductive habits and attitudes-and they need to understand how those old patterns developed in the first place.

Fitness facility owners and managers, program directors, group fitness instructors and personal trainers who learn how to provide this behavior change support can become more effective drivers of change-boosting client retention, creating business opportunities and helping people to achieve lasting success. Here's an introduction to the science that can help make that happen.

What is Behavior Change Science?

Behavior change science explores evidence-based methods that promote healthy behaviors, such as staying physically active, maintaining a healthy weight, and abstaining from tobacco and excessive alcohol use. Perhaps the best way to understand it is to see how it can be applied.


Bill Ross, NASM-CPT and Master Trainer and a health and life coach in Denver, shares this client story to illustrate how to apply behavior change science to fitness training:

Courtney* wanted to lose 180 pounds. She was an emotional eater with major fears of exercising in a gym. Ross and Courtney first addressed emotional eating. Courtney wrote down her thoughts and memories when she felt like she needed to eat. 

This activity helped Courtney realize every time she felt sad or upset as a child, she was given food. Understanding that she often ate when she wasn't actually hungry enabled her to identify her eating triggers and change this behavior.

Ross and Courtney also addressed her fear of being judged when exercising in front of others. He scheduled every training session for Courtney when a lot of people were around and kept Courtney's focus on the workout. 

After six sessions, Ross asked Courtney if she had noticed a person wearing a funny outfit. She answered no and realized that if she didn't notice that person, no one else was watching or judging her either. After 18 months of training, Courtney lost 160 pounds and changed her life forever.

Courtney's example shows that applying behavior change principles goes well beyond offering motivation and positive support. 

Courtney needed specific insights on the habits and ways of thinking that prevented her from achieving her fitness and weight loss goals. This case study also demonstrates how important it is to be specific when applying behavior change science, while making the information relatable rather than clinical.


"Using scientific principles of behavior change consists of knowing a client well, understanding the driving forces behind all behavior and [applying] the specific tactics a trainer can use to get results," says Erin A. McGill, MA, NASM-CPT, senior director of product development for NASM and AFAA. "It's the difference between telling a client, 'Do some cardio and do some pushups this week,' versus, 'We're going to do resistance training in a circuit-style format three times this week. Each session will be total-body exercises … and we will make sure you get benefits from both strength and cardiorespiratory training.' " As McGill points out, instead of relying on intuition, trainers can use proven methods of behavioral therapy to help people change bad habits for good.


"One misunderstanding by fitness professionals is that behavioral change science is very clinical," says Russell Wynter, NASM-CPT and Master Trainer, and co-owner of Madsweat in Scottsdale, Arizona. "I found that my clients respond better when it's kept light."

Applying behavioral science is just one part of the process to help make clients succeed, Wynter says. Using the NASM-BCS, an educational program on behavioral change science (see Case Study: John's Transformation), "gives us a systematic way to take our clients through making changes by using simple strategies that they can implement on a daily basis." However, fitness professionals can choose to share that information in a way that feels personalized and friendly, not clinical.

Theories of Behavior Change

Behavioral change scientific theories look at reasons underlying why people do what they do. Cognitive behavioral theory and social cognitive theory are most relevant to fitness and weight loss. CBT focuses on internal cues and the individual's role in altering their own negative perceptions, while SCT uses the external influence of positive social cues to inspire and support change in an individual.

Read more about the theories of behavior change.


People respond to their perception of a situation-not the objective facts. Cognitive behavioral theory, therefore, focuses on how a person's thoughts, emotions and behaviors are connected and affect one another. For example, eating in response to feelings of sadness or distress-instead of hunger-reveals the connection between emotions and behavior.

Cognitive behavior interventions help people identify thinking patterns that trigger these kinds of feelings so they can change the targeted behaviors (NASM 2014). In a cognitive behavioral study with 316 participants with obesity, intervention group subjects learned goal-setting, action-planning, barrier-management and self-monitoring strategies. 

At a 2-year follow-up, the investigators found that those who had learned these skills continued to lose weight, maintain exercise and follow healthy eating habits (Göhner et al. 2012).


People learn behaviors in social contexts and become influenced by personal and environmental factors. For example, if you see a role model do something, you're much more likely to do it yourself. Self-efficacy-a person's confidence to take actions to achieve goals regardless of obstacles-is another important aspect of this theory. 

Goal setting and positive reinforcement, therefore, are tools of this method to boost self-efficacy and increase the likelihood of successful behavioral change. For lasting weight loss and increased physical activity, social cognitive theory is the most-often-applied behavioral health theory in research studies (Joseph et al. 2016).

McGill offers an example of how a personal trainer would apply this method. "The trainer would say, 'We're going to work on your goals. Goal setting is important for a number of reasons. I want you to do the first draft, and then we will review them together next session. 

Think about your end goal and the things you have to do to get there. These are process goals.' Then, after goals have been set and are achieved, the trainer would offer the following: 'You did great this month and hit your goals. Your homework is to write up what was different and how it made you feel.' "

This example illustrates how a trainer can use positive coaching, goal setting and positive reinforcement. These tools build a client's self-confidence to achieve fitness and weight objectives. The trainer can help a client understand the specific behaviors they need to accomplish goals and to increase the chances of long-term success.

A "Change" That's Worth Making

Applying these theories to your own fitness training can be straightforward and ultimately make the difference between success and failure.

 "Incorporating behavior change principles with exercise science programming increases a trainer's value to each client, not only monetarily, but also as the expert who can help a client change behavior patterns that may have existed since childhood," Ross says. "My client success rate increased from 65% to 98% by implementing behavior change in training programs."

For fitness professionals who want to make a lasting impact on a client's life and health, understanding behavioral change science may be the ultimate key.

* Name changed for client confidentiality.

Program Yourself to Be an Agent of Change

The NASM Behavior Change Specialization

Learn the nuances of what makes people tick.

a person pushing over a row of dominos

You don't need to be a licensed psychologist to effect positive behavior change. What you do need, however, is a basic understanding of how to motivate people to change health and fitness habits. Learn practical evidence-based principles and specific intervention techniques in the NASM Behavior Change Specialization (BCS).

This course shows you how to:

  • Pinpoint motivational triggers and determine your clients' greatest barriers to change.
  • Apply the appropriate intervention techniques aligned with your clients' personality, and identify their ability to change.
  • Design programs that can yield quicker, more effective results, and help to raise client retention.
  • Adjust training methods as your clients progress in their training.


The NASM-BCS is delivered completely online.

The training includes:

  • online course
  • ebook
  • video lectures
  • learning activities
  • quizzes
  • final online exam

Quote: Behavior change strategies are evidence-based methods used to promote healthy behaviors, helping people adopt the habits required to reach their health and fitness goals.

Case Study: John’s Transformation

man on a mountain triumphantly holding a bike over his head

Russell Wynter, NASM-CPT and Master Trainer, and co-owner of Madsweat in Scottsdale, Arizona, shares this client story:

John* had an annual company physical and learned that he had high blood pressure, high cholesterol and prediabetes. He needed a life change. Wynter and John sat down together and made SMART goals (Specific, Measurable, Attainable, Realistic, and Timely-short- and long-term). Short-term goals included: Train three times per week, add 30 minutes of mountain biking twice per week and plan to increase riding to five times per week and increase time to 60 minutes. John's long-term goal was to compete in a mountain bike race-an unfulfilled dream of his.

In 1 year, John not only accomplished his long-term goal of competing in a mountain bike race, but also brought all of his health screening scores back into normal range. Applying behavioral change techniques in John's case not only fulfilled his dream-it transformed his health and life quality.

* Name changed for client confidentiality.

The Author

Shirley Archer, JD, MA

Shirley Archer, JD, MA

award-winning certified trainer and best-selling author of 16 books, blends evidence-based research and traditional wisdom to redefine pathways for optimal aging. Reach her at, @shirleyarcher (Twitter), @shirleyarcher (Instagram) and @shirley_archer (Pinterest).


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