Eight Weeks of Phosphatidic Acid Supplementation in Conjunction with Resistance Training Does Not Differentially Affect Body Composition and Muscle Strength in Resistance-Trained Men

摘要

This study attempted to determine the effects of eight weeks of resistance training (RT) combined with phosphatidic acid (PA) supplementation at a dose of either 250 mg or 375 mg on body composition and muscle size and strength. Twenty-eight resistance-trained men were randomly assigned to ingest 375 mg [PA375 (n = 9)] or 250 mg [PA250 (n = 9)] of PA or 375 mg of placebo [PLC (n = 10)] daily for eight weeks with RT. Supplements were ingested 60 minutes prior to RT and in the morning on non-RT days. Participants’ body composition, muscle size, and lower-body muscle strength were determined before and after training/supplementation. Separate group x time ANOVAs for each criterion variable were used employing an alpha level of ≤ 0.05. Magnitude- based inferences were utilized to determine the likely or unlikely impact of PA on each criterion variable. A significant main effect for time was observed for improvements in total body mass (p = 0.003), lean mass (p = 0.008), rectus femoris cross-sectional area [RF CSA (p = 0.011)], and lower-body strength (p < 0.001), but no significant interactions were present (p > 0.05). Collectively, magnitude-based inferences determined both doses of PA to have a likely impact of increasing body mass (74.2%), lean mass (71.3%), RF CSA (92.2%), and very likely impact on increasing lower-body strength (98.1% beneficial). When combined with RT, it appears that PA has a more than likely impact on improving lower-body strength, whereas a likely impact exists for increasing muscle size and lean mass.Key points class="unordered" style="list-style-type:disc">In response to eight weeks resistance training and PLC and PA (375 mg and 250 mg) supplementation, similar increases in lower-body muscle strength occurred in all three groups; however, the increases were not different between supplement groups.In response to eight weeks resistance training and PLC and PA (375 mg and 250 mg) supplementation, similar increases in lean mass occurred in all three groups; however, the increases were not different between supplement groups.In response to eight weeks resistance training and PLC and PA (375 mg and 250 mg) supplementation, similar increases in muscle mass (RF CSA) occurred in all three groups; however, the increases were not different between supplement groups.Supplementation of PA in conjunction with RT does not impose a differential benefit; however, regarding trends in the data magnitude-based inferences indicate that PA has a more than likely impact on improving lower-body strength, whereas a likely impact for increasing muscle mass when combined with resistance training.