Assessing the need to use sport supplements: The mediating role of sports supplement beliefs

Abstract

AimSport supplement use by athletes can lead to unintentional anti-doping rule violations (ADRVs) due to the contamination of prohibited substances. This phenomenon underscores the need for athletes to reconsider their supplement use and assess their safety, efficacy, and necessity—a process we referred to as ‘reconsideration of supplement use’. Additionally, a body of research using the Sport Supplement Beliefs Scale (SSBS) has shown that when an athlete believes that supplements improve performance, they may be more likely to progress to doping in the future. However, most research is conducted in English speaking countries and there is a lack of validated measures in other languages. Therefore, in this multi-study research, we validated a Japanese version of the SSBS (Study 1) and examined relationships between perceived risk of ADRV due to supplements, reconsideration of supplement use, sports supplement beliefs and sport supplement use (Study 2). MethodsIn Study 1, we created a Japanese version of the SSBS (SSBS-J) using back-translation. In order to evaluate the reliability and validity of the scale, we utilized data from 356 university athletes, which were divided into two distinct cohorts, who reported their frequency and number of supplements used. Internal consistency and fit of the SSBS-J were evaluated using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) and the scale's ability to determine supplement use was assessed using linear regression analysis and t-tests. In Study 2, 525 university athletes (64.6 % men, Mage = 18.7 ± 0.7 years) were asked to complete measures related to the perceived risk of committing an ADRV due to supplement use, SSBS-J and sport supplement use. ResultsIn Study 1, the SSBS-J showed high internal consistency (α = 0.876), a one-factor structure similar to the original version, and good model fit. Linear regression indicated that the SSBS-J scores were significantly associated with the frequency and number of supplements used and differences were found between scores of supplement users (21.51 ± 6.54) and non-users (16.48 ± 6.14) (p < .001). Discriminant analysis correctly classified 64.7 % of supplement users and 61.0 % of non-users. In Study 2, ADRV awareness was indirectly related to sport supplement use via sport supplement beliefs (p < .001). ConclusionsOur findings suggest that ADRV awareness can influence reconsideration of supplement use and subsequently deter supplement use mediated by sport supplement beliefs. These insights emphasize the importance of promoting doping risk awareness, revisiting supplement use, and mitigating sport supplement beliefs to reduce inappropriate or unnecessary supplement use among athletes. From an anti-doping perspective, this insight is valuable in guiding athlete education regarding supplement use.