Acute Oral Ingestion of a Multi-ingredient Preworkout Supplement Increases Exercise Performance and Alters Postexercise Hormone Responses: A Randomized Crossover, Double-Blinded, Placebo-Controlled Trial.J Diet Suppl. 2020; 17(2):211-226.JD
Multi-ingredient preworkout supplements (MIPS) are marketed as a means to increase exercise performance. The purpose of this study was to determine the effect of a single serving of Bang Pre-Workout Master Blaster (BMB) on upper- and lower-body power output and local muscular endurance. Ten resistance-trained males participated in two exercise testing sessions consisting of the vertical jump (VJ), seated medicine ball throw (SMBT), and local muscular endurance tests for the bench press (BP) and leg extension (LE) exercises at 70% of one-repetition maximum. Participants consumed placebo (PLA) or BMB 30 minutes prior to each exercise session. No difference between trials was observed for SMBT distance or BP repetitions. Vertical jump (p = .006) and LE repetitions (p = .014) were greater for the BMB trial compared with placebo. A significant interaction between trial and time was observed for insulin-like growth factor-1 (IGF-1; p = .044). Serum IGF-1 was significantly increased at both 30 PS (p = .004) and 30PX (p = .038) compared with BL for the BMB trial only. In conclusion, acute ingestion of BMB increased lower-body power and endurance as measured by the VJ and LE repetition tests, respectively, without altering hemodynamics. Furthermore, serum IGF-1 increased in response to acute exercise with BMB supplementation, but not with PLA. No differences in human growth hormone (HGH) or serum cortisol responses were observed between trials.