Abstract
Many high school athletes report using nutritional supplements. Due to a lack of education at the high school level, the use of safe for sports third-party tested nutritional supplements may be limited. To determine the impact of a short online nutritional supplement education program on safe dietary supplement behavior a cross-sectional repeated measures design was used. Therefore, a convenience sample of 106 high school athletes (14–19 years old) was recruited to measure pre-post education difference for nutritional supplement use and third-party tested (TPT) supplements. Additionally, it was analyzed if nutritional supplement related Theory of Planned Behavior (TPB) constructs were associated with athlete choices. The most popular supplements included protein powder (65%), caffeine from beverages (45%), and different types of vitamins (ranging from 38–44%). Consistent use of (safe) third-party tested individual supplements was low, ranging from 35–77% for the most frequently reported supplements. The combined TPB determinants explained 26% of the variance of the intention to use safe supplements (F3, 102 = 13.03, p < 0.001, Adj R2 = 0.26). The self-reported intention to use third-party tested supplements increased significantly (+7%–36% per individual supplement) after following the education program (Z = −3.288, p = 0.001) resulting in an intentional use of 54–94% TPT supplements. In conclusion, education resulted in more high school athletes reporting future third-party tested supplements use, and TPB construct scores did not change over time but could explain a substantial part of the variance of safe supplement use intentions.
Authors’ contributions
Study design FW, LM, HL, KS, HM, PHK; feedback on implementation of study design CS, HM, PHK; data collection FW, LM, HL, KS, CS; data analysis LM, HL, KN, PHK, FW; manuscript preparation FW, LM, KN, PHK; the final version of the manuscript was approved by all authors.
Disclosure statement
The authors report no conflict of interest, but FW received grants from external partners that were not related to this project. FW received grants from: Arizona Parks & Trails, Pac-12 Health and Wellbeing Initiative, the Collegiate and Professional Sports Dietetic Organization, Friesland Campina N.V., Standard Process Inc., Kraft Heinz Company, Unilever Corporation FEMA, and the Arizona Board of Regents.
Ethical standards disclosure statement
This study was conducted according to the guidelines laid down in the Declaration of Helsinki and all procedures involving human subjects/patients were approved by the Arizona State University Institutional Review Board (STUDY00016111). Two weeks before the start of the data collection, opt-out forms that included informed consent language were provided to parents of high school athletes via email by the school’s head strength & conditioning coach. If parents did not return the form, they agreed that their child was allowed to participate in the study (i.e. presumed consent).
Additional information
Funding
Notes on contributors
Floris C. Wardenaar
Floris Wardenaar, PhD is an assistant Professor and director of the Athleat Field Lab at the College of Health Solutions at Arizona State University in the USA.
Lindsay Morton
Lindsay Morton is an MS students in Nutritional Science at Arizona State University in the USA.
Kahyun Nam
Kahyun Nam is a PhD student at the LLT program of the Mary Lou Fulton Teachers College at Arizona State University in the USA.
Hannah Lybbert
Hannah Lybbert is an MS student in Nutritional Science at Arizona State University in the USA.
Kinta Schott
Kinta Schott is a PhD student at the ENS program of the College of Health Solutions at Arizona State University in the USA.
Colin Shumate
Colin Shumate, MS, is head strength and conditioning coach at Crean Lutheran High School in the USA.
Hans van der Mars
Hans van der Mars is a Professor emeritus at Mary Lou Fulton Teachers College at Arizona State University in the USA.
Pamela Kulinna
Pamela Kulinna is a Professor at Mary Lou Fulton Teachers College at Arizona State University in the USA.