What omega-3 does for training: what studies show on endurance, strength, muscle soreness and muscle growth, how much EPA and DHA you need, and the best vegan sources.
Omega-3 fatty acids, especially EPA and DHA, are worth paying attention to if you train, but they're not a shortcut to more muscle. Research suggests they may support endurance capacity and slightly reduce how sore you feel after hard sessions, while their effect on strength is very small and on muscle mass there is none. Athletes may be at higher risk of low omega-3 levels, and if you eat vegan, algae oil is the most reliable way to get EPA and DHA. This guide explains what the research shows, how much you need and which plant sources work.
What are omega-3 fatty acids?
Omega-3 fatty acids are polyunsaturated fats your body can't make on its own, so you need to get them from food. Three types matter most:
- ALA (alpha-linolenic acid) is the plant form, found in flaxseed, chia seeds, hemp seeds, walnuts and rapeseed oil.
- EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) are the long-chain forms. They're found in oily fish such as salmon and mackerel, and in microalgae, which is where fish get them from.
Your body can convert ALA into EPA and DHA, but only a small fraction of it. That's why ALA from seeds and nuts is useful, but it doesn't replace a direct source of EPA and DHA.
Do athletes need more omega-3?
Possibly. In its 2025 position stand, the International Society of Sports Nutrition (ISSN) concluded that athletes may be at higher risk of omega-3 insufficiency, and that omega-3-rich diets and supplements effectively raise omega-3 levels [1].
The level is often measured as the omega-3 index, the share of EPA and DHA in the membranes of your red blood cells. People who eat little or no fish, including most vegans, tend to have a lower omega-3 index unless they use an algae-based supplement [5].
What does omega-3 do for your performance?
Endurance and the heart
The ISSN found that EPA and DHA supplementation has been shown to improve endurance capacity and cardiovascular function during aerobic exercise such as running, cycling or swimming [1]. The effects in studies are modest, and they build up over weeks of regular intake, not after a single dose.
What is officially established in the EU: EPA and DHA contribute to the normal function of the heart, with a daily intake of 250 mg of EPA and DHA [8].
Strength
The ISSN states that omega-3 combined with resistance training may improve strength, depending on the dose and how long it's taken [1]. A 2023 meta-analysis of 14 studies with over 1,400 participants found the effect to be very small, though statistically significant, and it didn't depend on the dose or on whether people also did strength training [2].
Does omega-3 help build muscle?
No, not in young, healthy adults. The same meta-analysis found no significant effect of omega-3 on muscle mass or muscle function [2], and the ISSN also concludes that omega-3 may not offer a benefit for muscle growth in young adults [1].
If you want to build muscle, the levers that work are progressive strength training, enough energy and enough protein: about 1.6 g per kg of body weight a day for most people who train, spread over several meals [4].
Does omega-3 reduce muscle soreness?
Possibly a little. The ISSN concluded that omega-3 may reduce how sore people feel after intense exercise [1]. A meta-analysis of 12 trials found less soreness two days after eccentric exercise, but the difference was smaller than what people notice in practice, and strength and mobility recovered no faster [3].
So omega-3 isn't a recovery tool you'll feel after one session. If it helps, it's a small effect over time.
What else does omega-3 do?
- Brain and vision: DHA contributes to the maintenance of normal brain function and normal vision, with a daily intake of 250 mg of DHA [8].
- Sleep: omega-3 supplementation has been associated with better sleep quality, but it's not clear whether it causes the improvement [1].
- Immune system and head impacts: research is looking at how omega-3 affects immune cells in athletes, and whether taking it in advance could help protect athletes exposed to repeated head impacts. These are early findings, not established effects [1].
How much EPA and DHA do you need?
- Baseline for adults: the European Food Safety Authority sets an adequate intake of 250 mg of EPA and DHA a day [6].
- In sports studies: most studies on performance and recovery used around 1–3 g of EPA and DHA a day, taken over several weeks [1][2].
- Safety: according to EFSA, supplemental intakes of up to 5 g of EPA and DHA a day don't raise safety concerns for adults [7]. If you take blood thinners or have a medical condition, talk to your doctor before taking high doses.
When you compare supplements, look at the amount of EPA plus DHA per daily dose, not the total amount of oil. A 1,000 mg algae oil capsule might contain only 250–500 mg of EPA and DHA.
Should you take omega-3 before or after training?
Timing around your workout doesn't matter. Omega-3 works by building up in your cell membranes over weeks, so what counts is taking it regularly. Take it with a meal that contains some fat, which helps absorption and makes fishy-tasting burps less likely.
Vegan omega-3: plant foods and algae oil
Plant sources of ALA
| Food | Portion | ALA (approx.) |
|---|---|---|
| Ground flaxseed | 1 tbsp (10 g) | 2.3 g |
| Chia seeds | 1 tbsp (12 g) | 2.1 g |
| Walnuts | 30 g | 2.7 g |
| Hemp seeds, shelled | 30 g | 2.6 g |
| Rapeseed oil | 1 tbsp (10 ml) | 0.9 g |
ALA has its own authorised claim: ALA contributes to the maintenance of normal blood cholesterol levels, with a daily intake of 2 g [8]. A spoonful of ground flaxseed or chia in your oats or smoothie gets you there. Grind flaxseed, because whole seeds often pass through undigested.
Algae oil for EPA and DHA
A review of studies in vegetarians and vegans found that high doses of flaxseed or echium oil did not raise the omega-3 index, while microalgae oil raised it in every study [5]. If you eat vegan and want EPA and DHA, an algae oil supplement is the most reliable option.
Omega-3 checklist for active people
- ☐ Eat a daily source of ALA: ground flaxseed, chia, hemp seeds, walnuts or rapeseed oil.
- ☐ Get EPA and DHA from oily fish once or twice a week, or from an algae oil supplement if you eat vegan.
- ☐ Check the label for EPA + DHA per daily dose, not just the amount of oil.
- ☐ Take it regularly with a meal; the time of day doesn't matter.
- ☐ Don't expect more muscle from omega-3. Protein, energy and progressive training do that.
- ☐ Talk to your doctor before high doses if you take blood thinners.
"Omega-3 is one of the few supplements I'd actually recommend to most vegans, but for general health, not as a performance hack. A daily spoon of ground flaxseed plus an algae oil covers the basics." – Dr. Anna Falk, PhD chemist, sports nutritionist and founder of WAM
FAQ: Omega-3 for athletes
Does omega-3 help build muscle?
No, not in young, healthy adults. A 2023 meta-analysis found no effect on muscle mass and only a very small effect on strength. Muscle growth comes from strength training, enough energy and enough protein.
Should I take omega-3 before or after training?
It doesn't matter. Omega-3 builds up in your body over weeks, so take it regularly with a meal that contains some fat, at whatever time suits you.
How much omega-3 should athletes take?
EFSA's adequate intake for adults is 250 mg of EPA and DHA a day. Sports studies mostly used 1–3 g a day over several weeks, and up to 5 g a day is considered safe for adults. Check the EPA + DHA content per dose, not the total oil.
Does omega-3 help with muscle soreness?
Possibly a little. Studies found slightly less soreness after hard exercise, but the effect was small and strength didn't recover faster.
Can vegans get enough omega-3 from flaxseed?
Flaxseed is a great source of ALA, but your body converts only a small part of it into EPA and DHA. Studies found that flaxseed oil didn't raise the omega-3 index in vegetarians and vegans, while algae oil did.
Is algae oil as good as fish oil?
Algae oil provides the same EPA and DHA as fish oil, because fish get their omega-3 from algae in the first place. In studies, algae oil reliably raised omega-3 levels in vegetarians and vegans.
Plant-based nutrition with WAM Protein
Omega-3 covers your fats; protein covers your muscles. WAM Protein is a vegan protein powder from soy, pea and rice with 21–23 g of protein per 30 g serving, depending on the flavour, sweetened only with a small amount of stevia and never with sucralose. Add a spoon of ground flaxseed or chia to your shake for ALA too. Protein contributes to the growth and maintenance of muscle mass.
Try every flavour
The WAM Sample Pack has a sachet of every flavour, so you can find your favourite before buying a full bag.
The WAM Sample Pack has a sachet of every flavour, so you can find your favourite before buying a full bag.
Sources
[1] Jäger R, Heileson JL, Abou Sawan S, et al. International Society of Sports Nutrition Position Stand: Long-Chain Omega-3 Polyunsaturated Fatty Acids. J Int Soc Sports Nutr. 2025;22(1):2441775. PubMed
[2] Santo André HC, Esteves GP, Barreto GHC, et al. The Influence of n-3PUFA Supplementation on Muscle Strength, Mass, and Function: A Systematic Review and Meta-Analysis. Adv Nutr. 2023;14(1):115-127. PubMed
[3] Lv ZT, Zhang JM, Zhu WT. Omega-3 Polyunsaturated Fatty Acid Supplementation for Reducing Muscle Soreness after Eccentric Exercise: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Biomed Res Int. 2020;2020:8062017. PubMed
[4] Morton RW, Murphy KT, McKellar SR, et al. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018;52(6):376-384. PubMed
[5] Lane KE, Wilson M, Hellon TG, Davies IG. Bioavailability and conversion of plant based sources of omega-3 fatty acids – a scoping review to update supplementation options for vegetarians and vegans. Crit Rev Food Sci Nutr. 2022;62(18):4982-4997. PubMed
[6] EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA). Scientific Opinion on Dietary Reference Values for fats. EFSA Journal. 2010;8(3):1461. EFSA
[7] EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). Scientific Opinion on the Tolerable Upper Intake Level of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and docosapentaenoic acid (DPA). EFSA Journal. 2012;10(7):2815. EFSA
[8] Commission Regulation (EU) No 432/2012 establishing a list of permitted health claims made on foods. EUR-Lex
