Omega-3s Might Ease Sore Muscles After Workouts

The new 2025 review gathered human studies on omega-3 fats, usually from fish oil, around hard workouts. Researchers looked at delayed-onset muscle soreness (DOMS), strength and performance, and blood markers like creatine kinase and inflammatory cytokines.

They also checked dose and timing. Some trials lasted only a few days, while others ran for up to 10 weeks of daily omega-3 use.

“Omega-3s show promise for easing soreness, but the evidence for performance benefits is still inconsistent,” says lead author Atiporn Therdyothin, MD.

Exercise-induced muscle damage (EIMD) usually shows up after hard or unfamiliar workouts. You’re more likely to feel it after moves that load the muscle while it lengthens, like downhill running, lowering a weight, or jump training.

On a tiny level, repeated high force pulls the muscle fibers out of line. This can disrupt sarcomeres, the basic contractile units of muscle.

That structural damage makes muscle cell membranes leaky. Proteins like creatine kinase (CK) and myoglobin spill into your bloodstream, which is why they’re often used as lab markers of muscle damage.

The first mechanical injury then starts a second wave of inflammation. Signals like NF-κB and MAPK switch on, driving out prostaglandins, leukotrienes, interleukin-6 (IL-6), tumor necrosis factor (TNF) and other cytokines that recruit immune cells and create reactive oxygen species.

You feel that whole chain reaction as DOMS. Soreness usually starts within 24 hours, peaks around 24 to 48 hours, and can hang around for up to a week while strength and power dip.

The review found that omega-3s usually nudged soreness down, but only a little. A systematic review they cited found that omega-3 supplements reduced DOMS on average, yet the change was not big enough to count as a meaningful pain drop for many clinicians.

Most pain scores were checked at 48 hours after exercise. The authors say that may miss the real peak and the full recovery curve, especially for people who stay sore longer than average.

They argue that future trials should track soreness from 24 through 96 hours. It also helps to measure how long it takes for pain to return to baseline, not just how it feels at one random time point.

Longer-term use looked more promising. In one study, eight weeks of omega-3s almost brought soreness back to pre-exercise levels by day 5, while people on placebo were still complaining.

Another trial in resistance-trained lifters tested different doses. Only the highest dose—6 grams of fish oil per day for seven weeks—lowered soreness at 2, 48 and 72 hours after 80 eccentric squats.

Lower doses of 2 and 4 grams did not beat placebo in that group. So yes, both dose and training status may matter, which is very on-brand for exercise science.

Untrained or recreationally active people may see more benefit. In one small study, 3 grams per day for four weeks reduced soreness at 24 hours after a 60-minute downhill run, though not at later time points.

A 10-week trial in amateur endurance athletes used a high-DHA formula, about 2.1 grams DHA plus 240 milligrams EPA daily. It found lower soreness across all measured time points and parallel drops in a muscle damage enzyme called LDH-5.

However, nearly half the participants dropped out of that study. That makes the results harder to trust for everybody else.

Short-term loading—just a few days before a workout—was less convincing. Several studies using three to five days of high-dose omega-3s failed to reduce soreness in active men and women, even at intakes above 3 grams per day.

“It takes time for omega-3s to incorporate into muscle cell membranes, so you can’t expect a one-week miracle,” says Therdyothin.

When it comes to strength and performance, the picture is much fuzzier. Some trials report slightly better strength retention after muscle-damaging exercise with omega-3s, while others show no difference from placebo.

One problem is that studies use very different exercise models and tests. Some look at isometric knee extensions, others at squat jumps, sprints, or endurance tasks.

That mix makes it hard to compare results or combine the data in a useful way. Small sample sizes in many trials add yet another layer of “well, maybe” to the whole story.

Blood markers tell a similarly mixed story. In some studies, omega-3s appear to blunt rises in CK or LDH, suggesting less membrane damage or faster repair.

In others, enzyme levels and inflammatory cytokines like IL-6 and TNF look nearly identical between supplement and placebo groups. The review notes that trained athletes may show smaller changes in these markers no matter what they take, because their muscles are already tougher to damage.

That could help explain why some high-dose fish oil trials in resistance-trained people show little or no added benefit. For now, you should not count on omega-3s alone to save your strength after a brutal workout.

Omega-3s are not just generic “healthy fats.” EPA and DHA are built into cell membranes throughout your body, including muscle fibers and nerve cells.

Inside those membranes, they compete with omega-6 fats like arachidonic acid for the same enzymes. Arachidonic acid is the raw material for many classic pro-inflammatory messengers such as prostaglandin E2 and leukotriene B4.

By displacing some arachidonic acid in membranes, omega-3s can shift the balance toward less inflammatory signaling after muscle damage. They also reduce cyclooxygenase activity and can be turned into specialized pro-resolving mediators (SPMs).

These SPMs help shut down inflammation, clear immune cells from the injury site and promote a return to normal tissue function. On the pain side, SPMs can affect pain receptors and ion channels, which may calm both local and central nervous system sensitization.

“Omega-3–derived mediators seem to have genuine analgesic properties,” says co-author Nacharin Phiphopthatsanee, MD.

Omega-3s may also curb mitochondrial free radical production and improve nerve conduction velocity. In theory, that could support better voluntary muscle activation after damage, though direct evidence in athletes is still limited.

Finally, by changing membrane fluidity and stability, omega-3s might make muscle cells a bit more resistant to mechanical stress. That could mean fewer proteins leaking out during breakdown and a slightly smoother recovery.

If you’re curious about omega-3s for recovery, start with your plate before you reach for a pill. Focus on getting EPA and DHA from seafood and other whole-food sources first.

• Eat fatty fish like salmon, mackerel, sardines, herring or trout 2–3 times per week.

• Use canned salmon or sardines for quick lunches or post-workout meals.

• Pick omega-3–enriched eggs or dairy as easy extras.

• Add plant sources of ALA, like flax, chia, walnuts and canola oil, to support overall intake, even though conversion to EPA and DHA is limited.

If you consider supplements, keep your expectations realistic. The review suggests that any benefit for soreness is most likely when you:

• Use them consistently for several weeks, not just a few days before a big workout.

• Take a moderate-to-high daily dose, often 2–3 grams of combined EPA plus DHA, and up to 6 grams in some studies.

• Are relatively untrained or coming back to heavy eccentric work after a break.

• Pair omega-3s with an overall anti-inflammatory routine: enough sleep, balanced training, and a diet rich in plants and minimally processed foods.

You should also think about safety. Talk with your health care provider before starting high-dose fish oil, especially if you take blood thinners or have bleeding disorders.

More is not always better, and very high intakes can have downsides. They are not proven to improve recovery more than moderate doses used over time.

The new review reinforces a simple message: omega-3s are not a magic shield against sore muscles, but they may take the edge off DOMS for some people, especially with higher doses and longer use. Evidence that they reliably preserve strength or performance after hard exercise is still inconsistent.

“We see encouraging trends, but not enough high-quality, standardized trials to make firm recommendations for all athletes,” says Therdyothin.

For now, your best bet is to treat omega-3s as one small piece of a bigger recovery plan. Build a base of regular fatty fish and other whole foods, consider supplements if they fit your goals and medical profile, and keep focusing on the basics that matter most: smart programming, sleep, hydration and overall diet quality.