The Effectiveness of Fish Oil Supplementation in Attenuating Exercise-Induced Muscle Damage in Females During Mid-Follicular and Mid-Luteal Menstrual Phases.McKinley-Barnard, Sarah K.; Andre, Thomas L.; Gann, Josh J.; Hwang, Paul S.; Willoughby, Darryn S.Journal of Strength & Conditioning Research: Post Acceptance: September 11, 2017 doi: 10.1519/JSC.0000000000002247 Original Research: PDF Only Abstract The purpose of this study was to determine if the differences in estrogen levels during the female menstrual cycle and fish oil supplementation would attenuate eccentric exercise-induced muscle damage (EIMD) and delayed onset muscle soreness (DOMS). In a double-blind fashion, 22 physically-active females (20.9 +/- 1.4 years, 63.5 +/- 9.0 kg, 165.2 +/- 7.5 cm) were randomly assigned to ingest either 6 grams of fish oil (n = 11) or placebo (n = 11) daily for 21 days. Participants underwent an eccentric exercise bout of the knee extensors on two occasions during the mid-follicular (MF) and mid-luteal (ML) phases of the 28-day menstrual cycle. Prior to (PRE), at 6 (6HRPOST), and 24 hours post-exercise (24HRPOST) for each session, participants underwent assessments of DOMS, muscle strength, and had venous blood samples and muscle biopsies obtained. Data were analyzed utilizing a 2 x 2 x 3 repeated measures multivariate analyses of variance for each criterion variable (p <= .05). Further analysis of the main effects for Test was performed by separate one-way analyses of variance. DOMS was significantly greater at the 6HRPOST and 24HRPOST time points compared to PRE (p < .001). Superoxide dismutase and tumor necrosis factor-alpha (TNF-[alpha]) concentrations were significantly higher at the MF phase compared to the ML phase (p < .001 and p = .05, respectively). There were no statistically significant differences observed for muscle strength, myoglobin, NF-K[beta] p50 or NF-K[beta] p65. This study demonstrates that higher levels of estrogen may exert a cyto-protective effect on the sarcolemma. Copyright (C) 2017 by the National Strength & Conditioning Association.