1. Chapter 25 Ergogenic Aids
EXERCISE PHYSIOLOGY
Theory and Application to Fitness and Performance, 6th edition
Scott K. Powers & Edward T. Howley

2. Objectives Define ergogenic aid
Explain why a “placebo” treatment in a “double-blind design” is used in research studies involving ergogenic aids
Describe, in general, the effectiveness of nutritional supplements on performance
Describe the effect of additional oxygen on performance; distinguish between hyperbaric oxygenation and that accomplished by breathing oxygen-enriched gas mixture

3. Objectives
Describe blood doping and its potential for improving endurance performance
Explain the mechanism by which ingested buffers might improve anaerobic performances
Explain how amphetamines might improve exercise performance
Describe the various mechanisms by which caffeine might improve performance

4. Objectives
Identify the risks associated with using chewing tobacco to obtain a nicotine “high”
Describe the risks of cocaine use and how it can cause death
Describe the physiological and psychological effects of different types of warm-ups

5. Ergogenic Aid
A substance, appliance, or procedure (e.g., blood doping) that improves performance

6. Ergogenic Aids Research design concerns Placebo
Look-alike substance containing nothing that will improve performance
Athlete’s belief in a substance may influence performance
Double-blind studies
Neither the investigators nor the subjects are aware of who is receiving the treatment

7. Research Design Concerns
Amount of substance
Too little or too much may show no effect
Subject
May be effective in trained but not untrained subjects and vice versa
Task
Endurance vs. short-term events
Large-motor vs. fine-motor activities
Use
May enhance short-term performance but compromise long-term performance

8. Changes in Performance – the Placebo Effect
Fig 25.1

9. Nutritional Supplements
Little evidence that nutritional supplements improve performance
Supplements include:
Protein
Creatine
Carnitine

10. Aerobic Performance Oxygen breathing
Before or after exercise: no effect on performance
During exercise: improved performance
Blood doping
Infusion of RBCs in effort to increase hemoglobin concentration and oxygen carrying capacity of blood
Effective in improving VO2max and endurance performance

11. Oxygen Breathing
Fig 25.2

12. Blood Doping
Fig 25.3

13. Anaerobic Performance
Blood buffers (sodium bicarbonate)
Improves performances of 1-10 minutes duration or repeated bouts of high-intensity exercise
No benefit for tasks of less than one minute
Optimal dose
0.3 g•kg body weight-1 (with 1 liter of water)

14. Drugs Amphetamines Catecholamine-like effect
Improve performance in fatigued subjects only
No improvement in alert, non-fatigued subjects

15. Drugs
Caffeine
May improved performance at muscle, nervous system, or the delivery of fuel to muscle
Can elevate blood glucose and increase fat utilization
Effect is variable and dose-related
Effect may be diminished in regular users

16. Factors Influenced by Caffeine That Might Improve Performance
Fig 25.4

17. Mechanisms by Which Caffeine May Increase FFA Mobilization
Fig 25.5

18. Drugs
Cocaine
Powerful stimulator of cardiovascular and central nervous systems
May cause sudden death
Nicotine
Can stimulate both sympathetic and parasympathetic nervous systems
Cardiovascular or GI effects
Known to cause diseases of the mouth, including oral cancer

19. Mechanisms by Which Cocaine Can Kill
Fig 25.6

20. The Effects of Nicotine
Fig 25.7

21. Physical Warm-up
Causes both physiological and psychological changes that are beneficial to performance
Increased muscle temperature, arousal, focus on event
Warm-up activities
Identical to performance
Directly related to performance
General warm-up

22. Chapter 25 Ergogenic Aids