Excessive commitment to exercise and the relationship between dietary restraint and perfectionism : a case of moderation or mediation?

• Main Author: McLaren, Lindsay
• Format: Others
• Published: 1998
• Online Access: http://spectrum.library.concordia.ca/787/1/MQ39060.pdf; McLaren, Lindsay <http://spectrum.library.concordia.ca/view/creators/McLaren=3ALindsay=3A=3A.html> (1998) Excessive commitment to exercise and the relationship between dietary restraint and perfectionism : a case of moderation or mediation? Masters thesis, Concordia University.

Although excessive exercise and the personality characteristic perfectionism are both prevalent in eating disordered patients (especially in anorexia nervosa), the association between these two factors and the characteristic feature of dietary restraint has not been systematically investigated in a nonclinical population. The aim of the present study was to contribute to the understanding of this association by: (a) investigating the relationship between perfectionism and dietary restraint; and (b) exploring the moderating and/or mediating role of excessive commitment to exercise in this relationship. A university student sample of 269 women and 152 men completed paper and pencil questionnaires of dietary restraint, excessive commitment to exercise, and multidimensional perfectionism. Multiple regression analyses designed to test moderating and mediating models (Baron & Kenny, 1986) showed that higher perfectionism and more excessive commitment to exercise predicted more dietary restraint among both men and women ($p<.01$). No evidence was found to support the moderating role of excessive commitment to exercise on the relationship between perfectionism and dietary restraint. However, regression tests for mediation indicated that among women, excessive commitment to exercise mediated the relationship between self-oriented perfectionism and dietary restraint, and its inclusion significantly reduced the strength of two other relationships: between socially-prescribed perfectionism and dietary restraint, and between self-presentational perfectionism and dietary restraint. In men, excessive commitment to exercise mediated the relationship between self-oriented perfectionism and dietary restraint, but only when Body Mass Index (BMI) was controlled. The conclusion is that excessive commitment to exercise may explain some aspects of deviant eating symptomatology