It has been shown that there is a strong correlation between age and physical activity. The amount of physical activity decreases significantly with increasing age. This correlation was true regardless of gender. However, research has shown that participation in regular physical activity declines more in women than men (Butt Joanne, Robert Weinberg, Jeff Breckon & Randal Claytor, 2011). Studies have been conducted to investigate explanations for declines in participation in physical activity. Exploring motivations and goals for participation provided a better understanding of the decline in physical activity. Reasons for participation in physical activity among adolescent girls were both intrinsic and extrinsic. Goals and motivations for physical activity in the two contexts resonate with concepts and ideas from Self-Determination Theory (O'Dougherty Maureen, Kurzer Mindy & Schmitz Kathryn, 2010). Self-Determination Theory holds the idea that participation in physical activity stems from both intrinsic and extrinsic motivation. Intrinsic motivation is described as motivation associated with enjoyment of the activity while extrinsic motivation is externally imposed (O'Dougherty Maureen, Kurzer Mindy & Schmitz Kathryn, 2010). The self-regulation continuum is central to this theory. Proposed by this theory is the idea that a person's level or intensity of self-regulation varies on a continuum. These variations have important implications for the physical and mental well-being of the individual (Puente Rogelio & Anshel Mark, 2009). The four types of regulation are expressed in Self-Determination Theory. The four types of regulation are external, introjected, identifying and integrated. Exterior...... middle of sheet......ary, (2010). Coping with “bad body image days”: Strategies of young first-year college women. Body Image, 8(4), 335-342.Jankauskiene Rasa. and Kardelis Kestutis, (2005). Body image and weight reduction attempts among adolescent girls involved in physical activity. Medicine (Kaunas), 41(9), 796-801.O'Dougherty Maureen. , Kurzer Mindy, S., & Schmitz Kathryn, H. (2010). Changing motivations: Young women's reflections on physical activity over time and across contexts. Health Education Behaviors, 37(4), 1-19.Puente Rogelio. and Anshel Mark, H. (2009). Users' perceptions of their fitness instructor. Scandinavian Journal of Psychology, 51, 38-45. Sanda Solfrid, B., & Borgen Jorunn, (2011). Symptoms of eating disorders, drive for muscularity and physical activity among Norwegian adolescents. European Review of Eating Disorders, doi: 10.1002/erv.1156