(Healthline) – Fish oil is commonly taken to promote heart, brain, eye, and joint health.
Yet, bodybuilders and other athletes also utilize this popular supplement for its anti-inflammatory properties. Some people believe it may boost muscle strength, improve range of motion, and provide numerous other benefits.
As such, you may wonder whether fish oil can bolster your workout routine.
This article tells you whether you should take fish oil for bodybuilding.
What is fish oil?
Fish oil is extracted from the tissues of fatty fish, such as salmon, herring, halibut, and mackerel (1Trusted Source).
It’s high in omega-3 fatty acids, which are considered essential because you must obtain them from your diet. Your body cannot produce them on its own.
While several types of omega-3s exist, the two found in fish oil are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (2).
The U.S. Department of Agriculture (USDA) recommends that you eat at least 8 ounces (227 grams) of fish per week due to its fatty acid content (3Trusted Source).
You can also get omega-3s from plant foods, such as pine nuts, walnuts, and flax seeds, but these provide a less active form — alpha-linolenic acid (ALA) — than fish does (4Trusted Source).
Fish oil, which is extracted from oily fish, is rich in the omega-3 fatty acids EPA and DHA.
Potential benefits for bodybuilding
Fish oil may provide numerous benefits for bodybuilders largely due to its anti-inflammatory properties.
May reduce muscle soreness
It’s common to feel sore after working out.
In fact, some people begin to feel sore and stiff 12–72 hours after unfamiliar or exhausting exercise. This is referred to as delayed onset muscle soreness (DOMS), which may be caused by inflammation in your muscle cells (5Trusted Source).
DOMS commonly affects bodybuilders and can hinder workout motivation and performance (6Trusted Source).
While massage may reduce its symptoms, fish oil may also help by curtailing muscle damage and inflammation after resistance exercise (7Trusted Source, 8Trusted Source).
In a randomized study, 21 men performed bicep curls after 8 weeks of taking 2,400 mg of fish oil (containing 600 mg of EPA and 260 mg of DHA) daily. Fish oil inhibited the development of DOMS and prevented temporary muscle strength loss, compared with a placebo (9Trusted Source).
Similarly, a 14-day study found that women who supplemented with 6,000 mg of fish oil (containing 3,000 mg of EPA and 600 mg of DHA) daily significantly reduced the severity of DOMS following bicep curls and knee extensions, compared with a placebo (10Trusted Source).
May improve workout quality
Some research suggests that the EPA and DHA in fish oil may improve workout performance.
That’s because their anti-inflammatory properties may prevent or reduce a decline in strength and range of motion resulting from intense exercise.
In one study, 16 men took 2,400 mg of fish oil (containing 600 mg of EPA and 260 mg of DHA) daily for 8 weeks, then performed 5 sets of 6 bicep contractions. They maintained muscle force during the exercise and experienced less muscle swelling than those taking a placebo (11Trusted Source).
Another 8-week study in 21 men found similar results. Taking the same amount of fish oil daily lessened the temporary loss of muscle strength and range of motion after exercise (9Trusted Source).
What’s more, a 6-week study in 20 resistance-trained men following a low-calorie diet for weight loss showed that supplementing daily with 4,000 mg of fish oil (containing 2,000 mg of both EPA and DHA) maintained or even increased lower-body muscle strength (12Trusted Source).
As such, fish oil may help maintain muscle strength alongside dieting, which is a regular component of bodybuilders’ training.
Nonetheless, additional research on fish oil’s effects on muscle size and strength is necessary (13Trusted Source, 14Trusted Source).
May aid muscle health as you age
Aging is associated with the progressive loss of muscle mass. After age 30, muscle mass declines by 0.1–0.5% per year — with a dramatic increase in loss after age 65 (15Trusted Source).
As you age, it becomes more difficult to maintain and build muscle, partly due to a decreased response to both resistance training and protein intake (16Trusted Source).
Interestingly, the anti-inflammatory properties of fish oil may enhance your muscles’ sensitivity to protein and resistance training, allowing for greater gains in muscle size and strength as you age (17Trusted Source).
For example, a 16-week study showed that supplementing daily with 4,200 mg of omega-3s (containing 2,700 mg of EPA and 1,200 mg of EPA) significantly increased muscle growth after exercise in older adults, compared with younger adults (18Trusted Source).
Other studies likewise demonstrate that fish oil may boost or maintain muscle mass in older adults — particularly when combined with resistance training (19Trusted Source, 20Trusted Source, 21Trusted Source).
Though these results indicate benefits for middle-aged and older bodybuilders, more research is needed.
Due to its anti-inflammatory properties, fish oil may prevent or reduce muscle soreness, inhibit the temporary loss of strength and range of motion after exercise, and improve muscle sensitivity in older adults. Still, more studies are necessary.
Should you supplement with it?
Fish oil seems to be most effective for reducing DOMS, which is a common occurrence for many bodybuilders.
Yet, there’s insufficient evidence regarding its effects on muscle size or strength (22Trusted Source, 23Trusted Source).
Nevertheless, it may be worthwhile to take fish oil for your general health — especially if your diet is lacking in dietary sources of omega-3s — because this oil is linked to numerous benefits, such as improved heart health and reduced inflammation (24Trusted Source).
If you choose to take it, 2,000–3,000 mg per day of EPA and DHA is recommended for bodybuilders.
The EPA and DHA contents of fish oil supplements vary according to the type of fish and processing methods used, so make sure to read the nutrition label and serving size carefully.
According to the European Food Safety Authority, EPA and DHA supplements are generally well-tolerated and can be safely taken at combined doses of up to 5,000 mg daily (25).
Frequently reported side effects of fish oil include an unpleasant aftertaste, burping, heartburn, stomach discomfort, and diarrhea (2).
Although the scientific evidence supporting the use of fish oil for bodybuilding is currently limited, you may still want to supplement with it if your diet lacks food sources of omega-3s.