Effect of a pre-exercise energy supplement on the acute hormonal response to resistance exercise.

What Was Tested

Researchers studied Caffeine and Creatine in this randomized controlled trial publication.

The effect of a pre-exercise energy sport drink on the acute hormonal response to resistance exercise was examined in eight experienced resistance trained men.

Subjects were randomly provided either a placebo (P: maltodextrin) or the supplement (S: combination of branched chain amino acids, creatine, taurine, caffeine, and glucuronolactone).

Who Took Part

The age groups tagged for this paper are adults, men only.

How the Study Was Run

The design is described as randomized, double-blind, placebo-controlled and crossover.

Random assignment meant chance, not the researchers, decided who got Caffeine and who got the comparison, which limits bias.

Neither the participants nor the staff measuring them knew who was on Caffeine, so expectations could not easily colour the readings.

A placebo (an inactive look-alike) gave the Caffeine group a baseline to be compared against.

Each person switched between Caffeine and the comparison at some point, usually with a gap in between.

What Was Measured

Blood draws occurred at baseline pre-exercise, immediately post- (IP), 15 minutes post- (15P), and 30-minutes post (30P) exercise for measurement of serum growth hormone, total and free testosterone, cortisol, and insulin concentrations.

The subject headings attached to it are Amino Acids, Essential, Analysis of Variance, Area Under Curve, Blood Chemical Analysis, Caffeine, Creatine and Dietary Supplements.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of Caffeine and Creatine.

The publication is from 2008 (Journal of strength and conditioning research), a journal based in United States.

More context: all human trials.