The Impact of EFX® on ImPACT

Journal of Athletic Training. -


Kaufman, M. A., K. K. W. Tsang and L. M. Cardoza.



Context: Performance technology products embedded in silicone bracelets and necklaces are becoming increasingly popular with active individuals in the recreational and competitive athletic communities. Reports from users have indicated benefits in physical performance (e.g., balance, strength) and cognitive functions (e.g., alertness, concentration). Objective: The purpose of this research study was to examine the effects of EFX® ( on cognition. Design: Double blinded crossover study. Setting: Research laboratory. Patients or Other Participants: 30 healthy participants (males = 10, females = 20) (age = 21.67 ±2.4 years, mass = 67.6 ±13.2 kg, height = 167.7 ±8.5 cm) with no history of current or recent head injury. Interventions: EFX® is a commercial product, commonly marketed as silicone bracelets and necklaces, available via sporting goods department stores, sporting events, and the Internet. Each item contains a plastic dot that is reported to be “embedded with wearable holographic technology”. Independent variable was treatment condition: activated dot (EFX), non-activated dot (XFE), and no dot (CO). Participants completed one testing session consisting of a computerized program (ImPACT) under the three conditions. The order of treatment condition was randomized for each subject. Both the subject and test administrator were blinded to the order of the treatment conditions. ImPACT (ImPACT Applications, Inc.) is a commercially available computerized program commonly utilized as part of the neurocognitive assessment and management of concussions. Subjects complete six different modules from which composite scores are calculated for measurements of memory, reaction time, and processing speed. Main Outcome Measures: Dependent variables: composite scores for ImPACT: Verbal Memory (VRM), Visual Memory (VSM), Visual Motor Speed (VMS), Reaction Time (RT), and Impulse Control (IC). An ANOVA with repeated measures was used to assess differences between treatment conditions. Results: No differences between treatment conditions (mean ±SD) occurred for ImPACT: VRM (EFX 87.80 ±8.91, XFE 87.60 ±11.55, CO 85.97 ±10.23, P = .521, 1-β= .85), VSM (EFX 75.70 ±14.57, XFE 76.83 ±12.50, CO 72.90 ±15.19, P = .238, 1-β= .70), VMS (EFX 37.17 ±7.06, XFE 38.02 ±6.83, CO 37.69 ±6.90, P = .666, 1-β= .89), RT (EFX 0.552 ±0.05, XFE 0.560 ±0.05, CO 0.550 ±0.078, P = .598, 1β= .87), IC (EFX 5.93 ±4.2, XFE 7.80 ±8.35, CO 5.60 ±3.23,P=.108,1β=.61). Conclusions: Our results indicate cognition was not improved with the EFX® product. While most other studies have examined the effects of “performance technology” products on physical performance, our results are unique as they target variables of cognitive function. Our results do not support the positive testimonial claims but it should be noted no negative or hindered performance was demonstrated. Further investigation should be conducted to elucidate the influence of a “ceiling effect” with performance technology products.

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