Omega-3 fatty acids (omega-3) have anti-inflammatory properties. However, it is not known if omega-3 supplementation attenuates exercise-induced inflammation. We tested the hypothesis that omega-3 supplementation reduces inflammation that is induced by eccentric arm curl exercise. Healthy adult men and women (n=11; 35 ± 10 y) performed eccentric biceps curls on two occasions, once after 14d of dietary omega-3 restriction (control trial) and again after 7d of 3,000 mg/d omega-3 supplementation (omega-3 trial). Before and 48 h after eccentric exercise, signs of inflammation was assessed by measuring soreness ratings, swelling (arm circumference and arm volume), and temperature (infrared skin sensor). Arm soreness increased (p < 0.0001) in response to eccentric exercise; the magnitude of increase in soreness was 15% less in the omega-3 trial (p = 0.004). Arm circumference increased after eccentric exercise in the control trial (p = 0.01) but not in the omega-3 trial (p = 0.15). However, there was no difference between trials (p = 0.45). Arm volume and skin temperature did not change in response to eccentric exercise in either trial. These findings suggest that omega-3 supplementation decreases soreness, as a marker of inflammation, after eccentric exercise. Based on these findings, omega-3 supplementation could provide benefits by minimizing post-exercise soreness and thereby facilitate exercise training in individuals ranging from athletes undergoing heavy conditioning to sedentary subjects or patients who are starting exercise programs or medical treatments such as physical therapy or cardiac rehabilitation.

Dietary supplementation with omega-3 fatty acids has been shown to reduce inflammation in numerous inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease, and Chrohn’s disease.