In this case, study where a 25 years old female office worker Jessica is dealing with obesity. Jessica is forced to exercise because of constant mental harassment of her social background inclusive of her family and friends. To avoid this mental harassment she joined a gym where her first personal trainer told her to run 5 km a day. She ran 1 km a day as she was not physically active for the last seven years ultimately canceling her gym membership. After few months the mental harassment started again hence she joined the gym again with a new fitness instructor.
Self determination theory (SDT) a dialectical approach, it is a broad paradigm for inculcating motivation. Motivation may be intrinsic or extrinsic according to the nature of goals in order to achieve results. The intrinsic approach refers to self motivated person’s will and wishes to do activities that make us happy and the extrinsic approach refers to motivation which is triggered by rewards or avoiding punishments. Self determination theory (SDT) is greatly dependent on the competence of an individual in context to their skills, how the individual relates to the goal and the autonomy of the individuals where they feel in control of their own behaviors and set goals. Self determination theory (SDT) is greatly dependent upon a social, cultural, and relational aspect that may support or undermine an individual effort to attain and retain specific motivation. 
One key element of failure was her extrinsic decision to avoid mental harassment. Another aspect of this failure was the inability of the personal trainer to identify the tendencies of Jessica and completely overlooking Causality Orientations Theory (COT) where one must understand the personal tendencies and the abilities of the individual to look at the goals and achieve them 
She was physically inactive for the last seven years but she uses to dance when she was a teenager according to our first conversation. I being her new trainer suggested her very basic activities like walking as much as she can on the treadmill or outdoors and gradually increase the intensity of the workout. Secondly, I designed her a few basic dance classes where she does not require putting a lot of effort but could burns calories and gradually achieve the results by introducing her to the intrinsic approach of achieving a specific goal and stay motivated.
According to a study of 173 males, 192 females, 4 unspecified individuals ranging from 16 to 64 years of age. This study depicts results of 21 item scale utilized by Deci et al. (2001), 6 items measuring competence described as a sense of achievement from exercise, 8 items scaling relatedness described as people behavior around the individual, and 7 items measuring autonomy describing the choice of exercise of the individual. Participants responded to each item on a 7-point scale ranging from 1 (not true for me) to 7 (very true for me). This study clearly indicates the intrinsic motivation has a greater output. When people are self motivated with the choice of activities according to their personal strengths along right social behavior of the people around individuals has achieved higher results. 
4: A Test of Self-Determination Theory in the Exercise Domain, JEMMA EDMUNDS1 Coventry University United Kingdom, NIKOS NTOUMANIS AND JOAN L. DUDA University of Birmingham United Kingdom, Journal of Applied Social Psychology, 2006, 36, 9, pp. 2240–2265. r 2006 Copyright the Authors Journal compilation r 2006 Blackwell Publishing, Inc.