1. Sport Sciences for Health volume13, pages259–265(2017)

Chronic supplementation of omega-3 can improve body composition and maximal strength, but does not change the resistance to neuromuscular fatigue

Dhiego Mangilli Crestani, Érick Fernando Rodrigues Bonin, Ricardo Augusto Barbieri, Alessandro Moura Zagatto, Wonder Passoni Higino & Fabio Milioni

Abstract

Purpose

The present study aimed to determine whether supplementation with omega-3 fatty acid (N-3) contributes to improving body composition, strength performance, and neuromuscular fatigue resistance in physically active men.

Methods

The study was randomized, double–blind, and placebo controlled. 15 males were recruited and randomly assigned into two groups, N-3 supplementation (GN-3; N = 7) and placebo supplementation (GP; N = 8). Supplementation with N-3 or a placebo (safflower oil) was administered for 28-days at 1.4 g·day−1. During this period, physical activity was monitored (internal load = volume × perceived exertion scale). Before and after the supplementation period, body composition, one maximum repetition of knee extension (1RM), and maximum repetitions of knee extension with 70 % of 1RM load (RMs) pre and post an incremental running protocol until exhaustion were measured.

Results

ANOVA two way (p < 0.05) revealed a decrease in body fat mass (GP before: 8.3 ± 2.1 kg × after: 7.7 ± 2.4 kg; GN-3 before: 12.8 ± 9.4 kg × after: 11.8 ± 9.3 kg), increase in lean mass (GP before: 61.8 ± 4.1 kg × after: 62.7 ± 3.9 kg; GN-3 before: 64.2 ± 5.8 kg × after: 66.2 ± 6.0 kg), and 1RM (GP before: 111.3 ± 29.1 kg × after: 111.3 ± 25.9 kg; GN-3 before: 115.0 ± 36.2 kg × after: 129.1 ± 39.9 kg) in the GN-3, without significant alterations in the GP and no interactions between-groups. Moreover, the absolute variation of the RMs pre and post the incremental running protocol were not significantly altered for both group (GP before: −1.1 ± 2.9 repetitions × after: −1.1 ± 2.6 repetitions; GN-3 before: −3.9 ± 2.9 repetitions × after: −5.0 ± 4.6 repetitions), with no interactions between-groups.

Conclusion

Four weeks of N-3 supplementation seems to improved body composition and maximal strength of knee extension, without influencing neuromuscular fatigue resistance.