This document summarizes two studies on the effects of energy drinks and caffeine on athletic performance. The first study found that consuming Red Bull raised heart rate and lactate levels during exercise but saw no difference in repeated anaerobic cycling performance compared to a placebo. The second study found no significant difference in agility or anaerobic power between caffeine and placebo trials. Both studies suggest athletes should be cautious of relying on energy drinks or caffeine solely for performance enhancement.

1. Energy Drinks
By
Lee Cherry, BS
CPT, CSCS, HFS, USA Weightlifting
www.inhome-personaltrainer.com

2. Testing High Energy Drinks
• They are popular across many age groups and sometimes
used in athletics for a performance boost.
– Heavily marketed to younger athletes as a performance
enhancing substance and weightloss aide
• Most beverages in this category include similar ingredients:
– Hefty doses of caffeine and sugar, some B-vitamins, and a
sprinkle of amino acids.
• This particular study tested Red Bull, the self-described
original drink in this category.
– Red Bull contains
taurine, glucoronolactone, caffeine, niacin, vitamin B-
6, pantothenic acid, vitamin B-12, sucrose, and glucose.

3. Study
• The purpose of this study
– “The Effects of a Commercial Energy Drink on Repeated High Intensity
Anaerobic Cycling Performance”
• Was conducted to measure the effects of Red Bull on anaerobic cycling
performance.
– Published by Stefan M. Pasiakos, Robert Petrancosta, John Wygand, and Robert M. Otto)
• Methodology
– The study was a double-blind, placebo controlled, crossover trial in
which 13 male subjects participated.
– Trials consisted of a modified Wingate Anaerobic Power Test after
consumption of either Red Bull or a Red Bull-flavored placebo drink.
– The Wingate Anaerobic Power Test used in this trial consisted of six
bouts of 15-second supra-maximal cycling with a load equal to 0.1
kg/body weight with 45 seconds of recovery time between bouts.
– The data from this test can be extrapolated to other high intensity
sports, such as sprinting, basketball, and soccer.

4. Results
• The results showed that some of the resting
metabolic variables.
• Including heart rate and respiratory exchange
ratio, were significantly higher in the group that
consumed Red Bull vs. the placebo group.
• In addition, exercising heart rate and lactate
levels were significantly higher in the
experimental vs. the placebo group.
• There were no significant differences
seen, however, in repeated anaerobic cycling
performance in the two groups.

5. Take Home Message
• Take home message:
– Considering there were NO differences in
performance outcomes, it is recommended that
athletes not rely on Red Bull or similar energy
drinks when looking for performance assistance.
– Because such drinks raise athletes heart rates and
respiratory exchange ratios, they should especially
be avoided by athletes exercising in extreme heat.

6. Caffeine and Performance
• Caffeine is a known ergogenic aid. Research supports
this finding.
• It has been shown through numerous studies to
enhance endurance performance and increase mental
focus.
• The following study, The Effects of Caffeine on Athletic
Agility:
– by Andrew J. Lorino, Lisa K. Lloyd, Sylvia H. Crixell, John L.
Walker, and Jack W. Ransone)
• The study was conducted to examine whether caffeine
also has an effect on athletic agility and, therefore, on
overall anaerobic performance.

7. Study
• Sixteen adult men performed two trials of two drills
with two to three days of rest in between.
• They participated in a:
– Pro-agility run test to measure agility) and a…
– 30-second Wingate test (to measure anaerobic power).
• Subjects were not blinded for this study.
• They all received six mg of caffeine per kg of body
weight before one of the testing days, and a placebo
on the other.
• The order in which they received the supplement was
randomized.

8. Findings
• The researchers found no significant differences
between either the placebo or caffeine trials in
either of the outcome measurements.
• They suggested a number of possible limitations
to this study, however.
– The caffeine dosage may have been too low,
– Habitual caffeine use by some of the athletes may
have hindered the results, and…
– Training status of subjects could have influenced the
results.

9. Take Home Message
• Caffeine does work for many outcome
parameters, but this study did not prove it affects
agility and anaerobic performance.
• Most researchers suggest that athletes be very
careful before using caffeine as an ergogenic
aid, and this study reiterates that view.
– Study was published in the May 2005 issue of
Medicine and Science in Sports and Exercise, the
official journal of the ACSM. It can be accessed at:
www.ms-se.com.

10. Energy Drinks Available on Today’s
Market
• A Few Popular Brands
– Red Bull
– Monster
– NOS
– Rock Star
• Click Here For an “Extensive” List of High
Energy Drinks