Acute Turkesterone Dosing On Resting Metabolic Rate, Substrate Utilization, And Hemodynamic Variables In Recreationally-Active Males

Turkesterone is a relatively novel and increasingly popular phytoecdysteroid compound amongst recreationally active adults seeking to improve body composition. Although many of these hypothetical benefits stem from prior rodent substrate utilization data, no corroborative human data presently exist. PURPOSE: To determine the effect of multiple turkesterone doses on both resting metabolic rate (RMR), substrate utilization, and blood flow-associated resting hemodynamic variables in healthy humans. METHODS: Eleven recreationally active males (23.3±2.2y) visited the laboratory on three occasions separated by at least seven days and were randomized in single-blind, placebo-controlled, and counter-balanced crossover fashion to either 2000mg cellulose placebo (PLA), 1000mg turkesterone + 1000mg placebo, (1000T) or 2000mg (2000T) turkesterone. RMR and respiratory exchange ratio were assessed using a metabolic cart for 20 minutes prior to supplement provision (i.e. baseline [PRE]), as well as 60-minutes (POST60M), 120-minutes (POST120M), and 180-minutes (POST180M) post-acute supplementation timepoints at each visit. Resting heart rate was manually palpated and (systolic and diastolic) blood pressure was measured using an automated sphygmomanometer at the aforementioned timepoints. RMR, carbohydrate (CHO) and fat (FAT) oxidation, as well as all hemodynamic variables were analyzed using separate two-way (condition x time) ANOVA with repeated measures at a p<.05 significance level. RESULTS: Analyses failed to reveal any significant condition, time, nor interaction effects for RMR, CHO or FAT oxidation, nor any hemodynamic variable (p>0.05 in all cases). Despite extensive variation, it is noteworthy to mention that mean fat oxidation from PRE to POST60M, POST120M and POST180M increased more consistently in 1000T (17±75%, 35±89%, and 19±68%, respectively) and 2000T (4±30%, 2±35%, and 13±33%, respectively) versus PLA (13±31%, -7±20%, and -2±29%, respectively). CONCLUSION: Turkesterone supplementation resulted in no metabolic or hemodynamic parameter enhancements in recreationally active males. There were nonetheless mean fat oxidation differences that should be further explored to determine any longitudinal and/or exercise-dependent permissive impacts. The present research was funded by both the Baylor University Health, Human Performance, and Recreation Department Master's Thesis Research Grant and the Texas Chapter of the American College of Sports Medicine (ACSM) Student Development and Research Award.