Omega-3 Fatty Acids Supplementation did not Improve Cardiometabolic Benefits of 16 Weeks of Exercise Training

Abstract

PURPOSE: To determine if supplementation with omega-3 polyunsaturated fatty acids (omega-3 PUFA) either as enriched milk or capsules would improve the benefits of an aerobic exercise training program in the health of metabolic syndrome (MSyn) patients. METHODS: Four groups of MSyn patients were enrolled, in a 16-week high intensity interval training program combined with n3-PUFA supplementation administered in a double-blind randomized design. Thirty six MSyn patients ingested during the training program 500 mL of milk daily, either enriched with 275 mg of omega-3PUFA or, semi-skim milk as placebo. Another 40 MSyn patients received capsules containing either 846 mg of omega-3PUFA or soybean oil as placebo. Before and after intervention, MSyn components (i.e., waist circumference, blood pressure, blood glucose, triglycerides and HDL concentrations), composite MSyn Z-score, cardiovascular risk factors (total cholesterol (TC) and LDL), glucose metabolism markers (HbA1c and HOMA), body weight and composition, and cardiorespiratory fitness (peak oxygen consumption; VO2PEAK) and maximal rate of fat oxidation (FOMAX) were assessed. Data was analyzed using split plot ANCOVA (Time x Treatment) controlling for body weight loss. RESULTS: From the MSyn components, only blood pressure decreased significantly (P<0.001) after the exercise program without further benefit from omega-3 PUFA in any ingestion modality (P=0.340). MSyn Z-score, TC and LDL decreased significantly after training (P<0.001, P=0.016 and P=0.003, respectively) without differences among groups (P= 0.091, P=0.095 and P=0.156, respectively). HbA1c, HOMA and body weight did not change in any group (P=0.087, P=0.762, and P=0.203, respectively). However total fat mass decreased in all groups (P<0.001) without differences among treatments (P=0.942). VO2PEAK and FOMAX improved (P<0.001) in a similar fashion among experimental groups (P=0.651 and P=0.333, respectively). CONCLUSIONS: Sixteen weeks of dietary omega-3 PUFA supplementation either administered as functional food (enriched skim milk) or at a higher dose provided in capsules, did not further enhance the benefits of high intensity interval training in a group of metabolic syndrome patients.