The Development and Efficacy of a High School Athlete Education Program for Safe Nutritional Supplement Use.

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 (F_{3, 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.