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5 July 2023

Self-Determination Theory: A Practical Approach to Behaviour Change

by Luke Twyford 0

Realising an ambition often requires more than just physical strength, and many of us fail to realise the importance of psychology when it comes to achieving our goals. Unfortunately the process of working toward a health or fitness outcome is rarely straightforward, and oftentimes efforts can be thwarted by psychological factors. Moreover, many of us…

Realising an ambition often requires more than just physical strength, and many of us fail to realise the importance of psychology when it comes to achieving our goals. Unfortunately the process of working toward a health or fitness outcome is rarely straightforward, and oftentimes efforts can be thwarted by psychological factors. Moreover, many of us fail to recognise and address the reason why our goals go unrealised, resulting in individuals cycling through waves of undulating motivation, before ending up back at square one. As such, understanding the concept of behaviour change is crucial when attempting to re-direct efforts productively. 

As coaches, we at JPS play the role of troubleshooter, guide, and collaborator when working with clients. Not only do we investigate the reasons why clients struggle with motivation and behaviour change, but also work with them when finding and implementing solutions.  This blog will be exploring one of the ways in which we approach behaviour change, as well providing case studies which demonstrate its application.

Let’s start by exploring the theory… 

There are a number of methods that can be utilised when approaching behaviour change, however one that often stands out is Self-Determination Theory (SDT). Developed in 1985 by psychologists Edward Deci and Richard Ryan, SDT surmises that an individual’s social conditions can influence whether they are proactive and engaged with a task or goal, or passive and alienated (1)(2). Furthermore, SDT discusses the idea that we as individuals have three innate psychological needs, which when satisfied can enhance self-motivation –  something that is crucial when optimising adherence. So what are these needs?

Autonomy, the first aspect, involves having control over one’s actions and the ability to make decisions that align with one’s best interests. In a health and fitness setting, this might look like having input relating to programming variables, or having a say in what they believe is the best way for them to approach nutrition, i.e. opting for intuitive eating strategies, as opposed to tracking or a rigid meal plan. Autonomy could also be approached in a more in-direct manner, with an emphasis on self-monitoring progress, or setting personal goals relating to intrinsic factors such as health, longevity and strength. 

Up next is competence. This is the experience of mastery, and having confidence in one’s ability. This trait goes hand in hand with training, and can be reflected through the execution of new and increasingly challenging movements through incremental goals. In regards to nutrition, competence might be fostered through learning how to estimate the nutritional value of a meal or food item, learning how to track, or practising and improving mindful eating and moderation with indulgent foods. Being able to monitor progress is also key when achieving competence, and placing an emphasis on process outcomes as opposed to extrinsic goals, can play a central role in successful application.

Lastly, relatedness. This is a primarily social need that refers to the desire to feel connected with others, and a sense of belonging. Spending time in an environment that promotes relatedness can allow an individual to feel supported and welcome, whilst also providing external accountability. In a gym setting, relatedness can be reflected through the relationship between a coach and a client, two gym partners, or even gym members. Those that struggle with motivation and adherence may benefit from choosing the right environment to train in, and even finding relatedness outside of the gym, i.e. at work or home, can have a hugely positive impact on long-term success.

Once these three needs are fulfilled, SDT speculates that we are more likely to be self-motivated and willing to undertake tasks for inherent satisfaction and personal growth, as opposed to external reward, or due to shame or guilt. In theory, individuals that are self-motivated are more likely to have improved psychological wellbeing, and more likely to persist at important activities (3). For coaches, or those attempting to address their own behaviours, identifying these needs can be the first step when initiating and supporting behaviour change, inside and outside the gym. But what might this look like in a practical setting? 

Let’s take a look at some case studies from here at JPS headquarters:

  1. Having struggled for a number of years with weight gain and lack of adherence relating to training and nutrition, client T was finding that her all or nothing mindset with food was resulting in feelings of deprivation and regular binge eating episodes. In the past, client T had used macro/calorie tracking as means of controlling energy intake, however had found that the rigidity and pressure of hitting targets to facilitate fast fat-loss only exacerbated urges to binge. Change was obviously needed, and knowing that this particular client worked a high-stress and high profile job, the chosen strategy had to be flexible and sustainable for her lifestyle. This meant avoiding excessive restriction with nutrition, to help reduce the likelihood of reverting to unfavourable behaviours. 

As a starting point, Client T’s coach directed the focus to autonomy, in a bid to provide the client with more choice and control in relation to the process and her goals. Rigid tracking was then scrapped in favour of intuitive eating and mindful eating. This meant allowing a greater level of freedom with food choices, and emphasising that no foods were off limits on the condition that meals were more consistent across the week and indulgent foods were eaten in a controlled manner, i.e. eaten slowly and without distraction for the purpose of enjoyment. Although a deficit wasn’t established immediately, this time was vital for building consistency and ingraining a new thought process around food. From there, her Coach began to manipulate energy intake by adjusting portion sizes, whilst making changes to decision making when eating outside of home. Slowly but surely, scale weight began to drop and client T began to believe that she could achieve results, without being excessively restrictive or tracking every last calorie. The process was also no longer a burden for client T, meaning she could enjoy the journey knowing she was in control and able to improve her own health and wellbeing through her actions.

  1. Client N began training at JPS as a complete novice in his 70s. His goals were loosely related to improving general health and fitness, but he lacked any routine or consistency with exercise. Although clients without clear goals may not always face issues with adherence, making the process enjoyable and providing a clear sense of purpose can help foster ongoing progress. In this case, the focus was shifted towards competence, to help provide challenge and mastery.

From the start, client N clearly enjoyed the competence aspect of training, and so the introduction of technical movements directed the emphasis towards execution and technicality which could be clearly tracked from week to week. This meant starting with basic compound movements, and gradually increasing technical demands whilst decreasing restraints, each subsequent mesocycle. In addition to technical improvements, the exercise progression provided a sense of novelty and variety, further adding to enjoyment to the process. After 9 months, client N epitomises the idea of adherence, and has been able to make significant progress to his fitness, muscular strength, and endurance – all of which become increasingly more important later in life – without relying on extrinsic motivation to show up to sessions and apply effort.

  1. Clients L and S began training together at JPS for general aesthetics, however had fallen short of their goals in the past due to lack of adherence and inevitably, results. The two may have been able to rely on motivating themselves for a short time, however extrinsic motivation, i.e. looking a certain way, is unlikely going to be enough to sustain a consistent routine long enough to see meaningful change. Oftentimes, such individuals can easily end up spinning their wheels with training, moving through cycles of heightened intensity and commitment, before allowing themselves to veer away from the work needed to fulfil their goals due to other commitments or distractions. That said, the camaraderie the two shared showed a clear affinity for relatedness, something that their coach was able to identify and capitalise upon. 

At JPS, Clients L and S were able to thrive off the sense of community shared between coaches, clients and members, creating a desire to continue attending sessions and maintaining a routine with training and nutrition. In addition, having a coach who was able to share in this relationship further added to this sense of relatedness. Having started out as recreational lifters, clients L and S eventually challenged themselves to take their physiques to the bodybuilding stage together, a process that requires a large degree of commitment and effort. The two went on to achieve this goal, and have been able to maintain their training and nutrition habits post-competition. 

For these three clients, focusing on one element of self-determination became the catalyst for achieving results, however it’s important to note that the other two still needed to be present, in order to fully drive lasting behaviour change. Ultimately, the approach taken will need to be individualised, and it becomes your task to assess either your own, or your clients needs, to help with planning and decision making.

For coaches, an initial consultation is often the first and best time to gather information from a client as you have the opportunity to outline reasons why they are working towards a specific goal, and why they have not been able to succeed in the past. However, key aspects may only become apparent after a number of weeks/months, once a relationship has been established, and so flexibility should be factored into any programming or planning. When approaching your own training, identifying why previous endeavours have fallen short can still be a valuable exercise, however objectively assessing to what extent autonomy, competence and relatedness are present in your own environment may help you identify what needs to be done to fulfil areas that are lacking. 

In summary, the need for behaviour change often shows a need for a new strategy, and using self-determination theory to guide how you approach training and nutrition can allow you to address psychological needs which are central when fostering intrinsic motivation and lasting behaviour change. Whilst SDT states that autonomy, competence and relatedness all need to be accounted for, it’s possible that any one could be more or less present with a given individual. The JPS case studies provide examples of how a coach might analyse an individual’s needs and compose a plan accordingly, however this process may need to be undertaken by one’s self if a coach or trainer isn’t present. In these situations, it’s important to stay objective when assessing your social surroundings, and even identify why endeavours have fallen short in the past, to help provide a logical starting point when initiating change.


  1. Ryan, R. M., & Deci, E. L. (2000). Self-determination theory and the facilitation of intrinsic motivation, social development, and well-being. The American psychologist, 55(1), 68–78. https://doi.org/10.1037//0003-066x.55.1.68
  2. Migliorini, L., Cardinali, P., & Rania, N. (2019). How Could Self-Determination Theory Be Useful for Facing Health Innovation Challenges?. Frontiers in psychology, 10, 1870. https://doi.org/10.3389/fpsyg.2019.01870 
  3. Ryan, R. M., and Deci, E. L. (2017). Self-Determination Theory: Basic Psychological Needs in Motivation, Development, and Wellness. New York, NY: Guilford Publishing.

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