In a very recent study, scientists from the Unité de Formation en Sciences et Techniques des Activités Physiques et Sportives in France (Filaire. 2010) found that judo athletes who took a standardized omega-3 supplement (600 mg EPA and 400 mg DHA) for 6 weeks had significantly increased stress markers compared to placebo:
Significant interaction effects between supplementation and time on resting MDA [malondyaldehide] concentrations and Rmax were found (p = .03 and p = .04, respectively), with elevated values in the n-3 LCPUFA group after supplementation and no change in the placebo group's levels. The authors observed a significantly greater NO and oxidative-stress increase with exercise (MDA, Rmax, CDmax, and NO) in the n-3 LCPUFA group than with placebo.I've also read reports from (recreational) athletes all over the Internet claiming that whenever their PUFA supplementation goes beyond 1-2g per day, they start feeling drowsy, lose energy, recover slower and show other signs typically associated with increased inflammation. Feel free to use the comment function to let us know how fish oil or other omega3 sources make you feel.