Fish oils provide a source of essential omega-3 fatty acids that cannot be synthesized by the body and must be obtained from diet. Omega-3 fatty acids are an important component in cell membranes and play a role in regulating blood clotting, blood pressure, and inflammation. For these reasons, omega-3 fatty acids have been shown to benefit cardiovascular health and improve inflammatory conditions. Fish oil supplementation may also provide athletic performance benefits such as improving endurance and improved recovery by reducing inflammation and muscle damage. (Macaluso 2013, Shei 2014)
Omega-3 fatty acids have been shown to aid the transport of red blood cells through the capillary bed, which could improve oxygen delivery to muscle and therefore improve aerobic exercise performance (Shei 2014). It is also well established that physical performance is negatively effected by muscle damage and inflammation resulting from intense exercise. Omega-3 supplementation may reduce the inflammatory response in muscle tissue and reduce delayed-onset muscle soreness, which may decrease the recovery time between exercise sessions (Macaluso 2013).
There is no current evidence that fish oil supplementation is effective as an ergogenic aid in endurance exercise performance (Volpe 2012). Few studies have examined whether fish oil supplementation enhances endurance training adaptations and the evidence remains inconclusive, either showing no significant effects on aerobic performance or requiring longer term studies to show benefit (Macaluso 2013).
The literature also does not definitively support whether fish oil supplementation is effective at reducing inflammation and delayed-onset muscle soreness following exercise. The human data is not suggestive that taking fish oil lessens the inflammatory response to exercise leading to subsequent performance improvements (Shei 2014).
Further research is needed to determine effective dosing strategies for supplementing fish oil for athletic performance. For general health benefits the recommended dose is a minimum of 250mg/day of combined EPA/DHA fish oil. Higher doses (1-2g/day) have been used to evaluate effectiveness at improving performance and recovery. Side effects within the recommended dose are uncommon, but fish oil may decrease blood clotting, so caution must be used when taking higher doses that approach the FDA's safe daily recommended dose of ≤3g daily. (Shei 2014)
Jakeman JR, Lambrick DM, Wooley B, Babraj JA, Faulkner JA (2017). Effect of an acute dose of omega-3 fish oil following exercise-induced muscle damage. European Journal of Applied Physiology, 117(3), 575-582.
Macaluso F, Barone R, Catanese P, Carini F, Rizzuto L, Farina F, Di Felice V (2013). Do fat supplements increase physical performance?. Nutrients, 5(2), 509-24.
Shei R, Lindley MR, Mickleborough TD (2014). Omega-3 Polyunsaturated Fatty Acids in the Optimization of Physical Performance. Military Medicine, 179(11S), 144-156.
Volpe SL (2012). Fish Oil Supplementation and Athletic Performance. ACSMs Health & Fitness Journal, 16(5), 31-32.