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C H A P T E R 15. ERGOGENIC AIDS AND SPORT. w Learn the importance of including control groups and placebos when studying the ergogenic properties of a substance. Learning Objectives. w Discuss ergogenic aids—substances or phenomena that enhance performance above expected levels.
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C H A P T E R 15 ERGOGENIC AIDS AND SPORT
w Learn the importance of including control groups and placebos when studying the ergogenic properties of a substance. Learning Objectives w Discuss ergogenic aids—substances or phenomena that enhance performance above expected levels. w Find out the proposed ergogenic benefits, proven effects, and risks of several pharmacological, hormonal, physiological, and nutritional agents. w Discover which substances that have been considered ergogenic are actually ergolytic—they impair performance.
Examples of Ergogenic Aids in Sports w Football—anabolic steroids w Cycling—blood doping; amphetamines w Wrestling—diuretics, amphetamines w Distance running—phosphate loading Note: Scientific studies are limited by the accuracy of measurements and individual day-to-day variability. Events are won by hundredths of seconds or by centimeters.
Placebo Effect The placebo effect is when your ____________ of a substance ______________ your body’s response to it. While the effect is _______________ in origin, the body’s physical response to the substance is real.
PLACEBO EFFECT ON STRENGTH GAINS Subjects thought they were taking anabolic steroids during the 4 week training period.
Caffeine Effects Competitive cyclists pedaled to exhaustion at 80% VO2max after drinking a decaffeinated drink or a caffeinated drink – note that the lines for FFA are incorrectly reversed. The caffeine group exercised 20% longer than the decaffeinated group. McArdle, Katch, and Katch, Exercise Physiology, 2001
Changes in Weight Lifters during a 6-Week Treatment Period Difference due to increased aggression?
STEROIDS AND LEAN BODY MASS This graph summarizes results from a number of different studies.
STEROIDS AND STRENGTH GAINS Changes over 10 weeks of treatment with and without strength training
Steroid Precursors Androstenedione (“andro”) and dehydroepiandersterone (DHEA), both natural precursors of ________________, have been proposed to have ergogenic properties—increased muscle mass and strength—but research has not completely supported the claims that have been made. Andro – Over-the-counter substance; banned by IOC, NCAA, etc.; made famous by Mark McGuire DHEA – Over-the-counter substance; not banned
Natural DHEA Changes with Age McArdle, Katch and Katch, Exercise Physiology, 2001
. Effects of Blood Doping on Hemoglobin Concentration in the Blood Blood is drawn, RBCs are separated and frozen, then reinfused % (Lasse Virren – 1972 Olympics – 5 K and 10 K gold) Powers and Howley, Exercise Physiology, 1997
. VO2MAX AND FATIGUE AFTER BLOOD DOPING
OXYGEN SUPPLEMENTATION AND PERFORMANCE Subjects performed 2 60-second bouts of all-out cycling; oxygen or room air was administered during the 2 minutes between the bouts.
Effects of Bicarbonate Loading before and between Exercise Bouts The 5th bout was to exhaustion; the bicarbonate-loaded group went 42% longer than the control group.
BRANCED CHAIN AMINO ACIDS AND PERFORMANCE Effects of BCAAs on time to exhaustion during cycling at ~75% VO2max. There were no significant differences among the treatments.