Training Hard? 7 Ways Omega-3s Improve Your Fitness & Overall Health

Omega-3 fatty acids have long been praised for supporting heart, brain, and metabolic health. But when it comes to exercise performance and recovery, the guidance hasn’t always been crystal clear, especially for athletes and highly active people with higher physiological demands.

That’s why the new position paper from the International Society of Sports Nutrition (ISSN) matters. After critically reviewing the research, the ISSN released an official stance on how omega-3 fatty acids (specifically EPA and DHA) affect performance, recovery, immune function, brain health, sleep, and more in athletic populations. Here’s what you need to know.

Several studies show that omega-3 supplementation can improve running economy, aerobic capacity, and cardiovascular efficiency during endurance exercise. These benefits appear to stem from omega-3s’ ability to improve blood flow and oxygen delivery rather than directly boosting speed or power.

Research also suggests omega-3s can enhance red blood cell flexibility, endothelial function, and heart rate recovery after exercise. While improvements in actual endurance performance (like race times) are inconsistent, these cardiovascular adaptations may help endurance efforts feel more efficient.

Omega-3s are incorporated into skeletal muscle cell membranes, particularly the sarcolemma, which plays an important role in muscle remodeling and regeneration following endurance exercise. This suggests omega-3s may support the quality of muscle tissue, even if they don’t directly increase muscle size.

That said, when omega-3s are combined with resistance training, they may help improve strength over time, especially when taken consistently and at higher (but appropriate) doses.

These strength benefits tend to be more noticeable in less-trained individuals, while people who already lift regularly may see smaller or more subtle effects.

Recovery is one of omega-3s’ most talked-about benefits, and the ISSN paper largely supports this reputation, at least at a cellular level. Supplementation may help reduce indirect markers of muscle damage1 following intense exercise.

That said, results are mixed when it comes to how this feels subjectively. Some studies show reduced muscle soreness, while others show no difference. Importantly, omega-3s do not appear to blunt post-exercise inflammation, which is a normal and necessary part of adaptation.

High training volumes can temporarily compromise immune function, increasing the risk of upper respiratory infections that interfere with consistency and performance. Omega-3s appear to influence immune health by affecting immune cell activity and inflammatory signaling.

Studies in athletes suggest omega-3 supplementation can help regulate inflammatory cytokines, which may support immune resilience during periods of intense physical stress. Meaning? Omega-3s may help athletes better tolerate heavy training loads.

EPA and DHA are essential components of brain cell membranes and are critical for optimal cognitive function. Supplementation has been shown to improve neuronal membrane fluidity, neurotransmitter production, and cerebral blood flow.

These mechanisms suggest potential benefits for focus, reaction time, and mental resilience.

Still, it’s not yet clear whether these brain benefits lead to sport performance improvements in young, healthy athletes (more research is needed).

Some research links omega-3 supplementation to improved sleep quality, potentially due to anti-inflammatory effects and their influence on neurotransmitters like dopamine and serotonin, a precursor to melatonin.

If you’re looking for a nightly supplement to help you fall asleep and stay asleep, try this one. 

Omega-3s are actually classified as prebiotics, meaning they may help support a healthier gut microbiome. Prebiotics don’t have to be carb-containing food! They just have to support the growth of beneficial microbes in the gut. 

This is especially relevant for athletes, since high-intensity exercise can increase gut permeability (leaky gut) and disrupt microbial balance.

Early research suggests omega-3s may positively influence gut bacteria composition, and more research is underway to better understand this link.

Increasing your omega-3 intake

About 76% of people globally are not consuming enough omega-3 fats. Intense training, higher nutrient demands, and limited seafood intake also indicate that highly active individuals fall into this category. 

So how do you increase your intake? Integrate the right foods (with the right frequency) into your diet and start an omega-3 supplement. 

Food sources:

Fatty fish are the most reliable sources of EPA and DHA. Aim to get at least two servings of fatty fish a week. These fish include:

Plant foods like flaxseeds, chia seeds, and walnuts contain ALA omega-3 fatty acids, which the body can convert into EPA and DHA. However, that conversion is inefficient, so it’s near impossible to meet your EPA and DHA needs through plants alone.

Supplements:

EPA and DHA supplementation may be especially helpful for athletes, people who don’t eat fish regularly, or those with high training volumes.

Most studies cited in the ISSN paper use 1-3 grams of combined EPA and DHA per day, though optimal dosing may depend on body size, training load, and goals.

The takeaway

Omega-3s play such an important role in our long-term health. And they can help regularly active people get the most out of their fitness program by offering unique benefits for endurance efficiency, recovery support, immune resilience, and brain health in active people. 

Increasing your weekly fish intake is a great place to start to bump up your intake, but for more targeted and therapeutic benefits, opt for a high-quality omega-3 supplement.