Investigating the effect of 4-week fish oil supplementation on inflammation and plasma nitric oxide and reactive oxygen species in response to exhaustive exercise

Fish is an anti-inflammatory agent that different studies showed its effectiveness on reducing inflammation and improving performance, but its effect on peripheral fatigue mediators is not well understood. Therefore, present study performed in order to investigate the role of fish oil supplementation on tumor necrosis factor-α (TNF-α), nitric oxide (NO) and reactive oxygen species (ROS). For this purpose, 20 healthy students (age: 26.90±2.64 yrs, weight: 78.33±10.42 kg, height: 175.80±4.89 cm, body fat percent: 18.40±5.46%) were voluntarily participated in this study and assigned into control (corn oil) and experimental (fish oil) groups. Participants consumed fish oil for 4-weeks and their response to Bruce exhausting protocol investigated before and after supplementation. In each testing session, blood samples were taken before, immediately after and after 20-min recovery. In addition, ELISA method was used to analyze blood samples. All statistical analysis performed using SPSS software and level of significant defined as P<0.05. Our results showed significant decrease in baseline values of TNF-α and significant increase in baseline values of NO (P<0.05). In addition, two-way ANOVA results showed significant differences between groups after supplementation in changes of TNF-α after recovery (F=7.38, P=0.015) and changes of NO after exercise (F=5.64, P=0.034) and recovery (F=8.83, P=0.011). However, no changes observed in the case of ROS. These results showed that fish oil supplementation can reduce baseline inflammation and thus, increase baseline NO that can improve anti-oxidant capacity. However, TNF-α response to recovery increased that seems to be highly affected by increase in post-supplementation baseline. In addition, NO responses to exercise decreased that is maybe because of the lower physiological pressure of activity.