The Influence of a Pre-exercise Sports Drink (PRX) on Factors Related to Maximal Aerobic Performance

Overview

Journal J Int Soc Sports Nutr

Date 2010 Mar 13

PMID 20222976

Citations 3

Authors

Allyn Byars

Susan Keith

Warren Simpson

Andy Mooneyhan

Mike Greenwood

Affiliations

Soon will be listed here.

Abstract

Background: Pre-exercise sports drinks (PRX) are commonly used as ergogenic aids in athletic competitions requiring aerobic power. However, in most cases, claims regarding their effectiveness have not been substantiated. In addition, the ingredients in PRX products must be deemed acceptable by the athletic governing bodies that regulate their use in training and competition. The purpose of this study was to examine the effects of a modified PRX formulation (known as EM.PACT) from earlier investigations on factors related to maximal aerobic performance during a graded exercise test. The modification consisted of removing creatine to meet the compliance standards set forth by various athletic organizations that regulate the use of nutritional supplements.

Methods: Twenty-nine male and female college students varying in levels of aerobic fitness participated in a randomized crossover administration of PRX (containing 14 g/serving of fructose, medium-chain triglycerides, and amino acids mixed with 8 oz. of water) and placebo (PL) 30 minutes prior to performing a treadmill test with approximately one week separation between the trials. VO2max, maximal heart rate (HR), time to exhaustion (Time), and percentage estimated non-protein fat substrate utilization (FA) during two a priori submaximal stages of a graded exercise testing were evaluated.

Results: The VO2max mean value of the PRX trial was significantly greater than the PL trial (P < 0.01). The mean value for Time was also observed to be greater for the PRX trial compared to PL (P < 0.05). Additionally, percentage of FA during submaximal stages of the exercise test was greater for PRX trial in comparison to PL (P < 0.01).

Conclusions: The modified PRX formulation utilized in this investigation supports the findings of the previous investigation and its efficacy for enhancing indices of aerobic performance (specifically VO2max, Time, & FA) during graded exercise testing.

Citing Articles

The Effect of a Multi-Ingredient Pre-Workout Supplement on Time to Fatigue in NCAA Division I Cross-Country Athletes.

Fye H, Pass C, Dickman K, Bredahl E, Eckerson J, Siedlik J Nutrients. 2021; 13(6).

PMID: 34071868 PMC: 8228073. DOI: 10.3390/nu13061823.

The Effects of Sports Drinks During High-Intensity Exercise on the Carbohydrate Oxidation Rate Among Athletes: A Systematic Review and Meta-Analysis.

Li X, Wang W, Guo R, Wang A, Wei C Front Physiol. 2020; 11:574172.

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High fructose diet suppresses exercise-induced increase in AQP7 expression in the in vivo rat heart.

Karaca A, Palabiyik O, Tastekin E, Turan F, Vardar S Anatol J Cardiol. 2016; 16(12):916-922.

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