Introduction We have studied prohibited methods and substances in athletes of fitness at 2011–2012. This study aimed to determine the relations between cognitive variables (self-efficacy, locus of Control, and dysfunctional attitudes) and psychological factors towards prohibited methods and substances in fitness.

Methods 300 subjects investigated that comprised a case group of drug abuser and a control group. Each group contained male between 15 to 25 years. Participants were matched, based on salient demographics including age, sex, educational level and social class. The sampling method was simple random from various fitness clubs of Tehran, Iran. They were then studied by self-efficacy questionnaire, locus of control scale, dysfunctional attitude scale, and general health questionnaire. Hypotheses tested by variance analysis and Tukey's test. A structural equation model was developed based on the strength of relationships between these outcome measures.

Results Our findings showed that athletes abusing prohibited methods and substances had a lower self-efficacy, more dysfunctional attitudes, and exhibited external locus of control rather than control groups. They were also more sensitive to psychological morbidity. Most of relations were statistically significant.

Discussion In general, the possible reasons toward doping including: Increased energy levels.¹ Increase the visual beauty.² Develop a positive self-concept.³ Building self-confidence.⁴ Develop a psychological balance.⁵ The role of coach⁶. In this situation, abusing prohibited methods and substances may offer to the athlete a quick solution for coping with the extant pressure. Our findings were in accordance with the theoretical basis of cognitive psychology. More than 85% of all the athletes of fitness included in our study do rely on increased physical energy.