6. Pharmacological Agents
• Must know all drugs taken by the athlete
– Therapeutic use exemption in advance for certain
medical circumstances
– Otherwise athletes may forfeit medals, prizes,
awards
• Check drugs versus banned substances list
• Examples: sympathomimetic amines, b-
blockers, caffeine, diuretics, recreationally
used drugs
7. Pharmacological Agents:
Sympathomimetics
• Sympathomimetic amines
– Amphetamines (also ephedrine, pseudoephedrine)
– Medical and ergogenic applications
• Proposed benefits of amphetamines
– Weight loss
– Heighten concentration and focus
– Make athletes more competitive, induce sense of
being indestructible and euphoria
– Enhance performance, delay fatigue
8. Pharmacological Agents:
Sympathomimetics
• Proven effects of amphetamines
– State of arousal, energy, self-confidence
– Fatigue
– HR, blood pressure, blood flow, blood glucose,
FFAs
• Enhance performance by
– Weight loss
– Improving reaction time, speed, and focus
– Strength, power
– Max HR, peak lactate
9. Pharmacological Agents:
Sympathomimetics
• Risks of amphetamines, ephedrine
– Death, toxicity
– Heatstroke, cardiac stress
– Addiction (psychological, physiological)
– Masking of physiological danger signals
• Ephedrine and pseudoephedrine lack
benefits but still carry significant risks
10. Pharmacological Agents:
b-blockers
• b-blockers reduce sympathetic effects
– Used to treat cardiovascular disease
– Also for migraines, anxiety, stage fright
• Proposed benefits of b-blockers
– Decrease performance anxiety
– Enhance physical steadiness
11. Pharmacological Agents:
b-blockers
• Proven effects of b-blockers
– Resting, submaximal, and maximal HR
– Hand stability
• Risks of b-blockers
– Bronchospasm in asthmatics
– Cardiac failure, low blood pressure/dizziness
– Hypoglycemia (type II diabetics)
– Fatigue, impaired performance
12. Pharmacological Agents:
Caffeine
• Caffeine
– Central nervous system stimulant
– Sympathomimetic effects (but weaker)
• Proposed benefits of caffeine
– Mental alertness, feel more competitive
– More energy, reduced or delayed fatigue
– Enhanced mobilization of FFAs
– Glycogen sparing
13. Pharmacological Agents:
Caffeine
• Proven effects of caffeine
– Alertness, concentration, and mood
– Fatigue and reaction time (faster response)
– Fat metabolism
– All types of performance
• Risks of caffeine
– Nervousness, tremors, insomnia
– Headache
– GI problems
14. Pharmacological Agents:
Diuretics
• Diuretic clinical uses
– Increase urine production to reduce body water
– Control hypertension, edema
• Proposed benefits of diuretics
– Weight control
– Dilute other banned substances in urine samples
15. Pharmacological Agents:
Diuretics
• Proven effects of diuretics
– Significant temporary weight loss
– Resulting dehydration is ergolytic
– Plasma volume Qmax VO2max
• Risks of diuretics
– Impaired thermoregulation
– Electrolyte imbalance (including hyponatremia)
– Death
17. Hormonal Agents:
Anabolic Steroids
• Anabolic steroid use
– Androgenic: similar to male sex hormones
– Enhances anabolic function (builds bone, muscle)
– Athletes have become good at avoiding detection
• Proposed benefits of anabolic steroids
– Increased fat-free mass (FFM), strength
– Reduced fat mass
– Facilitate recovery after exhaustive exercise
18. Hormonal Agents:
Anabolic Steroids
• Proven effects on muscle mass, strength
– body mass, FFM
– Fat mass
– Total body potassium and nitrogen (FFM markers)
– Muscle size, strength
• Dose threshold for anabolic effects
– Small doses ineffective
– Large, chronic doses very effective
21. Hormonal Agents:
Anabolic Steroids
• High-dose testosterone same effects
– FFM
– Triceps and quadriceps area
– Strength
• Muscle mass increase is dose dependent
– Type I and type II cross-sectional area
– Number of muscle fiber nuclei
23. Hormonal Agents:
Anabolic Steroids
• Proven effects on cardiorespiratory
endurance
– Red blood cell production and total blood volume
– No effect on VO2max
• Proven effects on recovery from training
– muscle fiber damage after exhaustive lifting
– Rate of protein synthesis during recovery (rats)
24. Hormonal Agents:
Anabolic Steroids
• Issues with anabolic steroid use
– Moral and ethical concerns
– Fair competition (basis for World Anti-Doping Code)
• Sexual risks
– Men: early growth stoppage, supression of normal
hormones (testicular abnormalities), excess
estrogen (breast enlargement)
– Women: disrupted menstruation/ovulation,
development of masculine sex characteristics
26. Hormonal Agents:
Anabolic Steroids
• Emotional and psychological risks
– Aggression (“roid rage”)
– Violence
– Potential drug dependence
• Other risks
– Contracting hepatitis, HIV/AIDS
– Life span (mice)
– Incidence of birth defects
– Long-term effects of abuse unknown
27. Hormonal Agents:
Andro, DHEA
• Baseball steroids scandal
– Androstenedione (Mark McGwire) purported to
enhance testosterone production
– DHEA may enhance androstenedione, testosterone
• Studies generally show andro and DHEA
ineffective
– No significant strength gains
– Possible increase in estrogen
– Banned anabolic steroids more effective, popular
28. Hormonal Agents:
Human Growth Hormone
• Human growth hormone (hGH)
• Six proposed benefits of hGH use
– Stimulates protein, nucleic acid synthesis
– Stimulates bone growth (young athletes)
– Stimulates IGF-1 synthesis
– FFA mobilization, fat mass
– Blood glucose levels
– Enhances healing after injury
29. Hormonal Agents:
Human Growth Hormone
• Proven effects of hGH use
– Fat mass
– Young athletes: no anabolic effects
– Older men: FFM, bone density
• Risks of hGH use
– Acromegaly
– Cardiomyopathy, hypertension
– Glucose intolerance/diabetes
30. Physiological Agents
• Using any substance that occurs naturally
in body to improve performance
• Five major physiological agents
– Blood doping
– Erythropoietin (EPO)
– O2 supplementation
– Bicarbonate loading
– Phosphate loading
31. Physiological Agents:
Blood Doping
• Blood doping
– Any means by which red blood cell count increases
– Often through transfusion of previously donated red
blood cells
• Proposed benefits of blood doping
– Enhanced oxygen-carrying capacity
– Improved aerobic endurance and performance
• Proven effects of blood doping
– VO2max (long term)
– Aerobic endurance (short term)
33. Physiological Agents:
Blood Doping
• Maximizing benefits of blood doping
– Must reinfuse 900+ ml whole blood
– Must wait 5 to 6 weeks before reinfusion
– Must freeze (not refrigerate) stored blood
• Blood doping and endurance performance
– Enhances aerobic performance
– Benefit more evident in second half of race
35. Physiological Agents:
Blood Doping
• Risks of blood doping
– Blood becomes too viscous
– Excessive clotting, heart failure
– Some sports set hematocrit limits for competition
– Blood matching complications
– Exposure to bloodborne diseases
• Potential medical risks far outweigh
benefits
36. Physiological Agents:
EPO
• EPO slightly different from blood doping
– Natural kidney hormone
– Stimulates red blood cell production
• Proposed benefits of EPO
– Increased hematocrit
– Increased oxygen-carrying capacity
• Proven effects of EPO
– Hemoglobin, hematocrit, and VO2max
– Time to exhaustion
37. Physiological Agents:
EPO
• Risks of EPO use
– Dangerous increase in blood viscosity
– Blood clots, heart attack, heart failure, stroke
– Pulmonary embolism, hypertension
• Effects of EPO less predictable than those
of red blood cell reinfusion
38. Physiological Agents:
O2 Supplementation
• Proposed benefits of O2 supplementation
– Increase dissolved oxygen in blood
– Delay fatigue, speed recovery
• Proven effects of O2 supplementation
– Preexercise treatment little or no effect
– During exercise work, work rate, metabolic
efficiency, peak blood lactate levels
– After exercise no effect
39. Physiological Agents:
O2 Supplementation
• Risks of O2 supplementation
– No known risks
– Safety needs further research
– Oxygen equipment potentially dangerous
• Overall, simply not practical
40. Physiological Agents:
Bicarbonate Loading
• Proposed benefits of bicarbonate loading
– Increased blood pH and buffering capacity
– Delayed onset of anaerobic fatigue
• Proven effects of bicarbonate loading
– 300 mg/kg all-out performance for 1 to 7 min
– Enhanced H+ removal from muscle fibers
• Risks of bicarbonate loading
– GI discomfort (bloating, cramping)
– Sodium citrate similar results without risks
42. Physiological Agents:
Phosphate Loading
• Proposed benefits of phosphate loading
– Enhanced PCr resynthesis
– Enhanced oxidative phosphorylation
– Greater O2 unloading at muscle
• Proven effects of phosphate loading
– Findings equivocal
– Some studies no effects, others V
̇ O2max and time
to exhaustion
• No known risks of phosphate loading
43. Nutritional Agents:
Amino Acids
• L-tryptophan
– Proposed effects: analgesic, delays fatigue
– Proven effects: no improvement
• Branched-chain amino acids (BCAAs)
– Proposed effects: delay fatigue
– Study showed no effect from or BCAAs
• HMB (leucine metabolite)
– Some evidence may FFM, strength but unclear
– Decreases cholesterol, LDL, blood pressure
45. Nutritional Agents:
L-Carnitine
• Proposed benefits of L-carnitine
– Enhanced fatty acid oxidation
– Glycogen sparing
• Proven effects of L-carnitine
– Conflicting results
– Most findings negative
46. Nutritional Agents:
Creatine
• Creatine
– Widespread use (recreational to professional)
– Target: skeletal muscle
• Proposed benefits of creatine
– Increased muscle PCr content
– Enhanced peak power production
– Serves as buffer, helps regulate pH balance
– Enhanced oxidative metabolic pathways
47. Nutritional Agents:
Creatine
• ACSM conclusions regarding creatine
– Enhances high-power-output activity
– Maximal strength not affected
– With resistance training strength gains
– Results do not live up to expectations
• Creatine + exercise = FFM, strength
• May not improve performance
48. Nutritional Agents:
Contamination of Supplements
• Supplement marketing and labeling not
overseen by FDA
• Purity of supplements and accuracy of
supplement labels suspect
• Contamination with banned substances can
lead to disqualification, forfeit of medals
