Electrolyte-based Carbohydrate Drink: Effect On Steady State Exercise Done Against Progressively Higher Workloads

Abstract

Aerobic exercise with progressively higher workload stages done in succession challenges a person’s cardiorespiratory system as their VO2max is estimated. Higher heart rates (HR) at the end of stages lowers a person’s estimated VO2max. Adding electrolytes to a carbohydrate-based drink may raise VO2max values if ingested before exercise. PURPOSE: Compare the merits of added electrolytes, in two otherwise similar beverages, when consumed before VO2max tests that entail progressively higher workload stages stages. METHODS:In a randomized double-blind study subjects (13 men, 21 women) first gave written informed consent, followed by two stationary cycle ergometer workouts to estimate their VO2max. Workouts were preceded by intake of a 2% sucrose solution, one of which was an electrolyte-rich (500 mg of vitamin C, 1 mg of B-12, 100 mg of Mg+2, 400 mg of K+, 200 mg of Na+, 1 μg of Cr) beverage, while the other was devoid of added electrolytes and served as a placebo. HR were recorded before, four times during, and after workouts. Ratings of perceived exertion (RPE) were provided at the end of workouts. HR were compared with a three-way (gender, treatment, time) ANOVA, with repeated measures for treatment and time. Estimated VO2max and RPE were assessed with two-way (gender, treatment) ANCOVAs, with repeated measures for treatment. Body mass and body fat percentage were examined as covariates. Scheffe’s served as our post-hoc and a α= 0.05 denoted significance. RESULTS:There were significant inter-time differences for HR. RPE and VO2max each had inter-gender differences. Yet there were no inter-treatment differences. CONCLUSIONS:Little research exists on the ergogenic effects on electrolyte formulations added to carbohydrate beverages, yet our results concur with studies that also saw a lack of inter-treatment differences.