Supplementation with n-3 polyunsaturated fatty acids does not impact physical performance but affects n-6 polyunsaturated fatty acid levels

[Display omitted] •21-day supplementation with n-3 PUFAs do not affect physical performance.•N-3 supplementation decreases n-6 polyunsaturated fatty acids level.•Adrenic and dihomo-γ-linolenic n-6 acid levels are lower after n-3 supplementation. Although the usual focus is on how n-3 PUFA supplementation affects athletes’ health, questions remain as to whether short-term supplementation affects anaerobic performance and how this type of supplementation is associated with exercise-induced changes in n-6 PUFA content. Physically active young healthy men were assigned to two groups to determine the effect of 21 days of n-3 PUFA supplementation (the study was completed by 9 subjects receiving 3250 mg n-3 PUFA supplement daily, and 15 subjects receiving placebo filled with aqueous solution). Physical performance was measured by double Wingate aerobic test (WAnT). Blood was collected for analysis at four-time points (baseline and 24 h after WAnT, both before and after 21 days of supplementation). The n-3 and n-6 PUFAs were analysed by gas chromatography-mass spectrometry. A significant increase in the n-3 PUFA (140.1 %, p ≤ 0.01) content and decreased dihomo-γ-linolenic (DGLA) (26.5 %, p ≤ 0.01) and adrenic (AdA) (28.3 %, p ≤ 0.01) acid content were observed in the supplementation group compared to the placebo group following supplementation. No exercise-induced changes in PUFA content were observed. Concluding, n-3 PUFA supplementation modified PUFA content in favour of n-3 PUFAs at the expense of some n-6 PUFAs (DGLA and AdA).