Tiger Woods says his experience with the “calming” alkaloid l-theanine in the form of Gatorade Tiger Focus, “is taking me someplace I never imagined.” An article in The Gazette, May 24, 2009 details some of the research on theanine and the “tea paradox” of how a caffeinated beverage can be described as “calming.”
A relaxed, awake state is associated with Alpha waves, and an awake and excited brain will emit high frequency Beta waves. Caffeine can be shown to suppress theta and alpha waves, while promoting the beta waves that are linked with stress and anxiety. So, what does theanine do?
A number of studies have confirmed that within 30 minutes of ingesting theanine, there is a measurable enhancement of alpha wave activity, implying an alert but relaxed state.
And while clinical studies to date don’t show an improvement in memory or mental function in humans, rodent studies show some promise. The dose of theanine in the Gatorade product, 25 mg per serving, is below the levels used in studies, but tea itself does fall within the range of use that affects alpha brain waves.