The substance use profiles of a sample of obligatory and non‐obligatory exercisers

There is a growing body of literature that suggests participating in physical activity has beneficial physical and psychological effects. Mixed findings have been found regarding the association between physical activity and substance use. For example, physical activity has been associated with increased levels of alcohol use but lower rates of tobacco use among college students but adolescents may be placed at a higher risk of substance use depending on the sport in which they participate. Overall, the relationship between physical activity and substance use may be influenced by such factors as gender, age, the substance under investigation, the nature of physical activity and the level of intensity of the activity performed. The aim of this study was to investigate whether there exists an association between obligatory exercise (defined as a compulsive behaviour pattern in which exercise dominates daily life at the expense of other activities) and substance use by examining any differences in the substance use profiles of obligatory and non-obligatory exercisers. Men recruited from five gymnasiums in Sydney, Australia, were invited to complete an Internet-based survey between January and June 2005. Participants were asked to complete a brief survey asking about the past six month use of illicit substances (including cannabis, amphetamines, cocaine, inhalants, hallucinogens and sedatives/hypnotics); supplements/conditioning aids (including vitamins, protein supplements, creatine, caffeine, amino acids, diet pill and diuretics); and feelings of obligation to exercise as measured by the Obligatory Exercise Questionnaire (OEQ). The OEQ is a 20 item questionnaire scored on a Likert scale ranging from 1=never to 4=always. A score of 50 or greater is an indicator for exercise dependence. A total of 229 surveys were completed; using strict data screening measures, 67 were excluded for reasons such as identifying as female, where no gender was specified, living outside of Sydney or where incomplete data was obtained on the OEQ. Due to ethical restraints, no individually identifiable information was collected as part of the survey. The IP address from the computer submitting information to the server hosting the survey, by normal course of operation, was collected, though this was not collected in the dataset with the survey responses and therefore could not be linked back to individual responses. The study was approved by the University of Sydney Human Research Ethics Committee. The obligatory (n=31) and non-obligatory (n=131) exercisers were similar in age (mean age 30 years vs. 31 years; t 158 =0.573; p=0.568). The obligatory exercisers were more likely to identify as heterosexual (54.8% vs. 29.5%; OR=2.9; 95%CI=1.3, 6.5; p=0.008). There were differences between the two groups regarding the past six month use of supplements/conditions aids. Obligatory exercisers were significantly more likely to report the past-six month use of protein supplements (83.9% vs. 48.8%; OR=5.4; 95%CI=2.0, 15.1; p<0.001), vitamins (83.9% vs. 62.0%; OR=3.2; 95%CI=1.1, 8.8; p=0.021), creatine (45.2% vs. 27.1%; OR=2.2; 95%CI=1.1, 5.0; p=0.045) and amino acids (41.9% vs. 17.1%; OR=3.5; 95%CI=1.5, 8.2; p=0.003). Only one difference was found regarding the use of illicit substances, with obligatory exercisers less likely to report past six month use of cannabis (16.1% vs. 37.2%; OR=0.3; 95%CI=0.1, 0.9; p=0.025). Obligatory exercisers did not report greater use of illicit substances, but were more likely to use a range of supplements/conditionings aids. The study is unable to comment on the direction of this relationship – does the use of these substances represent a marker for a greater involvement in physical activity or does greater involvement in physical activity facilitate the use of these substances? Given that legal supplement use may remove barriers to using anabolicandrogenic steroids, which are associated with a range of physical and psychological harms, the relationship between physical activity and sporting supplement use should be investigated further.