The use of "energy" drinks for potential enhancement of daily activity and sport performance has continued to increase in popularity. One of the more popular drinks on the market is the 5-Hour Energy Shot®. The maker claims that "you feel awake and alert for hours" and it contains as much caffeine as a cup of the leading premium coffee. Published research to support claims of increased alertness and/or function for immediate and extended time frames is lacking.
PURPOSE: To determine if the 5-Hour Energy Shot® can enhance short- and long-term cognitive function.
METHODS: Eleven (8 males, 3 females), college-aged (22.1 + 3.75 yrs), volunteers participated in a double-blind, cross-over, placebo-based study. The participants completed five computer-based tasks (www.lumosity.com) prior to ingesting either a non-caffeinated placebo (P) (59 ml; 5 cals) or the 5- Hour Energy Shot® (5 HES) (59 ml; 4 cals) in a randomly assigned order. The five computer-based tasks included: Trail Making B (TM-B) to test for attention capacity, Wording Equations (WE) for math processing speed, Go/No-go (G/N) for reaction time, Digital Span (DS) for short-term memory, and Reverse Memory Span (RMS) for working memory. Data were collected prior to drink ingestion, and each hour subsequent to ingestion for a five-hour period. Subjects were also evaluated for subjective focus, alertness, distraction, tiredness, and drink effectiveness at each of same time points. A 2 × 6 ANOVA with repeated measures was utilized to determine if there were significant differences between the P and the 5 HES treatments across the six test periods. Significance was established at p < 0.05.
RESULTS: There was no statistically significant difference between P and 5 HES across the six time periods relative to the five computer-based tasks. There was a 15% increase in attention capacity, in the TM-B test data, with the 5 HES trial comparing pre-test (48.05 + 13.26 s) to one-hour post-ingestion (40.89 + 11.33 s). At one-hour post-ingestion, 90% of 5 HES and 20% of the P subjects reported that the drink was working effectively.
CONCLUSION: The 5- Hour Energy Shot® did not significantly improve short- or long-term cognitive function for selected computer-based tasks despite a high level of perception that it was working effectively compared to a placebo with college-aged participants.