Omega-3 fatty acids consist of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and alpha linoleic acid (ALA). EPA and DHA are the fatty acids primarily found in fatty fish, whereas ALA is typically found in plant oils, nuts, and seeds (1). These three fatty acids are considered essential as the body does not produce them in sufficient quantities. Therefore, these fatty acids must be obtained in the diet. ALA can be converted to EPA and DHA in the body, but the conversion rate is extremely low (3-10%) in humans partially due to typical western diets consisting of too much Omega-6 fatty acids (1). The lack of EPA and DHA consumption in typical western diets as well as the higher Omega-6 intakes throws off the ratio of omega-3 to omega-6 fatty acids that would be considered ideal for optimal health (1).
It is for this reason that omega-3 supplementation, with a particular emphasis on EPA and DHA, has become more and more popular in recent decades. In fact, omega-3 supplementation has a large body of evidence to support its health benefits, particularly for improving cardiovascular health and reducing the risk of cardiovascular disease and cardiovascular-related mortality from stroke and heart attacks (2). Omega-3 fatty acids have a vast array of other health benefits too, however, including beneficial impacts on nervous system function and immune function. Athletes have become interested in omega-3 fatty acids due to the beneficial effects of these compounds on inflammation. Dietary omega-3 fatty acid consumption has the potential to reduce inflammation, which is proposed as a way to enhance recovery from strenuous exercise (1).
I became interested in the potential benefits of omega-3 fatty acids for endurance athletes after I started working to improve my diet. I have recently transformed my diet to reduce my intake of added sugars and processed foods while also increasing my consumption of fruits, vegetables, nuts, seeds, and other nutrient-dense foods. I went as far as getting a comprehensive micronutrient panel done so that I could further optimize my diet to eliminate micronutrient deficiencies. I don’t regularly consume fatty fish, so I knew I was likely not consuming enough omega-3 fatty acids in my diet. This was when I turned to a high-quality fish oil supplement, mainly for general health benefits. However, then I started looking at the potential performance benefits that omega-3 fatty acids have for endurance athletes. I will do my best to summarize what I found in the section below.
What Is the Impact of Omega-3 Fatty Acid Supplementation on Endurance Performance?
There was a really nice review article published in Research in Sports Medicine by Dr. Philpott and colleagues (1) discussing the applications of omega-3 fatty acid supplementation for sports performance. One of the subsections of this paper was specifically focused on the research surrounding omega-3 fatty acid supplementation for endurance sports performance.
There is some research and limited evidence to suggest that omega-3 fatty acid supplementation may enhance mitochondrial biogenesis (the formation of more mitochondria), which would of course be particularly beneficial to endurance athletes as the more mitochondria would mean a greater capacity to utilize oxygen to breakdown glycolysis by-products and fat for fuel during exercise. However, this research was conducted in rodents and obese individuals, so the direct application to endurance athletes is lacking at this point.
There is a bit more evidence, however, demonstrating that omega-3 fatty acid supplementation can reduce the oxygen cost of submaximal endurance exercise as well as reduce submaximal exercise heart rate due to the beneficial effects that EPA and DHA have on stroke volume and muscle cell insulin sensitivity. There is actually some research in cyclists demonstrating this, however, these reductions in oxygen cost and heart rate did not translate into objective cycling performance improvements in time trials. So, despite potential physiological changes from omega-3 fatty acid supplementation in endurance athletes, it has yet to be demonstrated that this translates into real-world performance improvement.
Finally, there is the potential for omega-3 fatty acid supplementation to reduce the risk of upper respiratory tract infection (URTI) among endurance athletes due to the beneficial immunomodulatory effects of omega-3 fatty acids. Endurance athletes can be at a greater risk of URTIs, especially during periods of heavy training load. Therefore, if omega-3 fatty acid supplementation can reduce this risk and keep endurance athletes healthy with fewer bouts of illness, then this would theoretically have a positive downstream effect on performance as athletes would not miss training as often due to illness. However, again, there is limited data that directly demonstrates fewer bouts of illness when endurance athletes consume omega-3 fatty acids either from food or via supplementation.
As you can tell from reading the above, most of this research involving omega-3 fatty acid supplementation in endurance athletes is still very limited and inconclusive due to such limited studies being done. However, my personal opinion is as follows: If you do not regularly consume foods rich in omega-3 fatty acids, either starting to consume foods high in omega-3 fatty acids or taking a high-quality omega-3 fatty acid supplement is not likely going to impair endurance performance and can only improve your overall health. There is, of course, the potential for it to improve your endurance performance via the mechanisms outlined above. However, even if omega-3 fatty acid intake does not translate to objective performance enhancement, it will still likely improve your health as there are myriad health benefits to be had from regular intakes of omega-3 fatty acids in the range of 1-2 grams/day of EPA/DHA (1,2). This could certainly be something to consider if you do not consume enough omega-3 fatty acids in your diet on a regular basis.
Philpott JD, Witard OC, Galloway SDR. Applications of omega-3 polyunsaturated fatty acid supplementation for sport performance. Res Sports Med. 2019 Apr-Jun;27(2):219-237. doi: 10.1080/15438627.2018.1550401. Epub 2018 Nov 28. PMID: 30484702.
Bernasconi AA, Wiest MM, Lavie CJ, Milani RV, Laukkanen JA. Effect of Omega-3 Dosage on Cardiovascular Outcomes: An Updated Meta-Analysis and Meta-Regression of Interventional Trials. Mayo Clin Proc. 2021 Feb;96(2):304-313. doi: 10.1016/j.mayocp.2020.08.034. Epub 2020 Sep 17. PMID: 32951855.
Happy training and racing!
-Ryan Eckert, MS, CSCS
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