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Transcript
Chapter 27:
Ergogenic Aids and the
Female Athlete
Jacalyn J. Robert-McComb, Ph.D., FACSM
Shannon L. Jordan, M.S.
Texas Tech University
Health, Exercise, & Sports Science
Learning Objectives
 Discuss potential reasons female athletes
take supplements
 Highlight likely supplements female
athletes take
 Describe the ergogenic and ergolytic
effects of these supplements
 Discuss standard dosages
What is an Ergogenic Aid and
Why Do Women Take Them?
 Ergogenic aids are items or substances which
enhance performance.
 Collegiate female athletes report taking
supplements for the following reasons:
 to improve health;
 to compensate for an inadequate diet; and
 to gain more energy.
According to Kristiansen, et al.
(2005) and Froiland, et al. (2004),
 Female athletes use energy drinks and
carbohydrate/meal replacement products the
most.
 Protein products, amino acids, creatine, fat
burners, caffeine, multivitamins, iron, and
calcium are some of the most frequently
used products.
Protein and Amino Acids
Most common forms:
Powders
Bars
Meal Replacers
Amino Acids
Listed Reasons Why Females Take Protein
Supplements (Kristiansen, 2005)
For enhanced recovery
The taste
To provide Energy
To meet nutritional needs
For enhanced performance
To develop greater muscle strength
 ‘I Don’t Know’
Forms of Protein
Soy Protein vs. Milk Protein
Soy protein
Lacks the essential amino acids, lysine, and methionine; also
contains less branch chained amino acids than milk proteins.
Milk protein
Casein protein is a milk protein as is whey protein.
Net protein synthesis is higher with casein protein than with soy
protein.
Casein protein has a higher biological value because the slow
release property keeps the amino acids from being released
rapidly and degraded in the liver into urea (Luiking, Deutz, Jake,
et al., 2005).
Whey protein is considered rapid release when compared to
Casein (slow release preferred).
Glutamine
Commonly a component of weight-gain products (a
small % of female athletes take this supplement).
Claims:
Enhance protein Synthesis
Offset immunosuppression
However, no long term studies substantiating these
claims or ruling out adverse effects
Carnitine
Synthesized from lysine and methionine.
Most healthy humans synthesize carnitine
Athletes take L-Carnitine for:
Weight loss purposes
Increased muscle mass
Enhanced β-oxidation
Enhanced recovery from high intensity
 exercise.
L-Carnitine (an isomer )Findings
Effective weight loss agent for obese subjects, however,
findings were inconclusive for non-obese subjects
(Karlic & Lohninger, 2004).
Research findings have shown that athletes who have
taken L-carnitine to enhance recovery from exercise
have :
Decreased creatine kinase
Decreased Catabolism of purines
Decreased free radical formation
Decreased reported muscle soreness
L-Carnitine Dosage
Available as a prescription or OTC
Daily recommendations are 2-3.5g/d
Amounts in excess of 4g/d may result in
gastric distress
A lethal dose (LD) of 630g/d for humans
has been determined from animal studies
(Calfee & Lohniger, 2004)
Creatine
Composed of:
Arginine (non-essential amino acid)
Glycine (non-essential amino acid)
Methionine (essential amino acid)
Average Daily Requirement is 2g/d.
Body produces 1-2g/d.
Best sources of dietary creatine are meat and fish
Vegetarian athletes may have lower muscle creatine
stores.
Fat Burners and Energy
Supplements
The following supplements will be highlighted:
Chinese Ginseng
Siberian Ginseng
Ephedra (Ma Huang)
Bitter Orange
Caffeine
Creatine Supplementation Benefits
And Recommended Dosage
Optimum usage is for sports with a high percentage of ATP-PC system
utilization.
No effects have been found on submaximal efforts
No effects have been found for aerobic endurance activities
Dosage
Loading phase: 5g/d, 4 X’s/d up to 7 days
Maintenance phase: 2g/d for 3 months
Increases muscle creatine stores 10-25%
When creatine is taken with carbohydrates absorption is enhanced.
When creatine is taken with caffeine absorption is inhibited.
Ginseng
Reported Benefits:
Improved Mood
Improve Performance
Increase Alertness
Increase Fat Utilization
Two Main Types of Ginseng:
Chinese Ginseng (Panax ginseng)
Siberian Ginseng (Eleutherococcus
ginseng)
Chinese Ginseng
Reported Benefits (Bucci, 2000; Winterstein &
Storrs, 2001)
Improves Strength
Improves aerobic capacity
Requires at least 8 weeks of supplementation
with athletic training to see benefits.
Recommended Dosage:
1-2g/d
Varies based on powder vs. root extract
Chinese Ginseng
Reported Side Effects (Bucci, 2000; Winterstein &
Storrs, 2001):
Sleeplessness
Nervousness
Hypertension
Dermatological problems
Morning diarrhea
Euphoria
Rx Drug Interactions:
Phenelzine (A monoamine oxidase inhibitor)
Siberian Ginseng
 Distant relative to Chinese ginseng
 Contains different compounds than Chinese ginseng
 Previous studies were not conducted well and are
unreliable
 The few well-designed studies have failed to show
an ergogenic benefit (Winterstein & Storrs, 2001).
Ephedra
Contains ephedrine and other alkaloids
Sympathomimetic
α and β-agonistic properties
Facilitates catecholamine release
Stimulates the CNS
Uses:
Energy Booster
Fat Burner
Athletic Performance Booster
Ephedra
Also called Ma Huang
Studies often pair ephedra with caffeine
Legality of ephedra is still being determined
May be banned by various athletic governing
bodies
Ephedra Research Findings
Many studies also involve caffeine, therefore, the
effects due to ephedra are hard to separate from
caffeine (Shekelle, et al. 2003).
Studies without caffeine do not support the claim
of enhanced athletic performance (Calfee, 2006;
Bucci, 2000)
Claims of weight loss have been substantiated,
although many of those studies also contained
caffeine (Powers, 2001; Shekelle, et al., 2003).
Side Effects of Ephedra (Calfee, 2006; Powers, 2001;
Shekelle, et al., 2003 ; Winterstein & Storrs, 2001).
Headache
Tremors
Hypertension
Arrhythmias
Insomnia
Nervousness
Increased heart rate
Note: It has also linked to several deaths!
Bitter Orange: A Replacement for Ephedra
Citrus aurantium
Common ingredient in many “Ephedra Free” fat burners
Contains synephrine
Similar effects as ephedra
Commonly paired with caffeine (Bucci, 2000)
Caffeine
Varsity female athletes listed these reasons for taking caffeine:
Enhanced Performance
More Energy
Increased alertness
Taste
Listed forms Taken:
Beverages
Tablets
Energy Bars, Drinks, and Gels
Chocolate
Caffeine: Mode of Action (Graham, 2003)
Chemical structure resembles adenosine
Binds to adenosine receptors
Stimulates release of epinephrine
Direct mode of action on muscle function
•Causes sarcoplasmic reticulum to release more calcium
Caffeine has been reported to:
Enhance β-oxidation
Spare Muscle Glycogen
Sustain Muscle Force Longer
Caffeine and Performance
High Intensity Exercise (Doherty, et al., 2004):
Lower Perceived Exertion
Increased Glycolytic Performance*
Increased Blood Lactate*
* Not all studies have shown increased performance in glycolytic activities
and blood lactate (Greer et al., 1998)
Endurance Exercise:
Main concept id that of fatty acid moblization and glycogen
sparing
Prolongs Endurance Exercise **
** Mechanism behinds enhanced endurance performance not completely
understood
Caffeine: Adverse Effects
Mild Diuretic
Dehydration not likely if athlete is properly hydrating
Tachycardia with Exercise
Increased Blood Pressure
Gastrointestinal Distress
Habituation/Addiction
There are also effects when discontinuing use:
Headache
Fatigue
Possible Flu-like Symptoms
(Ghram, 2 001; Mangus & Trowbridge, 2005)
Caffeine: Dosage
Caffeine paired with ephedra is potentially harmful and
should be avoided (Powers, 2001; Mangus & Trowbridge,
2005 ).
Dosage:
Endurance Exercise:
3-5mg/kg
Since most beverages are variable in the amounts
contained, tablets are probably the most effective
method.
Anabolic-androgenic Steroids (AAS)
AAS are synthetic derivatives of testosterone.
Adolescent female usage is estimated between 2-5% (Congeni
& Miller, 2002; Faigenbaum et al., 1998).
Collegiate use may be higher (Evans, 2004)
Women typically have <10% the amount of testosterone of men
(Evans, 2004).
Testosterone and AAS bind to androgen receptors inside the
cytoplasm and are transported to the nucleus.
This leads to an increase of structural and contractile proteins.
(Congeni & Miller, 2002; Calfee & Fadale, 2006; Evans, 2004)
AAS: Ergogenic Effects
Anabolism
Anti-catabolism
Aggression
May lead to more intense training
Gains:
Muscle Hypertrophy
Strength Gains
Lean body Mass Increases
(Congeni & Miller, 2002; Tokish, et al., 2004)
AAS: Adverse Effects
Virilizing Effects:
Hirsutism
Voice Deepening
Male-pattern Baldness
Enlargement of the Clitoris
Menstrual Irregularities
Reduced Breast Size
Continued…………
AAS: Adverse Effects Continued
Increased Blood Pressure
Left Ventricular Hypertrophy
Decreased HDL
Hepatic Abnormalities
Dermatological Problems
Psychological Effects
Mood swings
Aggression
Note: Some of these effects are irreversible! The adverse effects far
outweigh the benefits for women (Congeni & Miller, 2002; Calfee &
Fadale, 2006; Evans, 2004)
AAS: Withdrawal Symptoms and other Repercussions
Withdrawal Symptoms:
Depression and Anger (Congeni & Miller, 2002; Calfee &
Fadale, 2006)
Injection Related Complications:
Inflammation from repeated use of injection site
Bacterial Infections
Infectious Diseases
Hepatitis B and C
HIV (Calfee & Fadale, 2006; Evans, 2004)
Multivitamins
Female athletes stated these reasons for taking multivitamins:
Meet Nutritional Needs
Boost Immune System
Boost Energy
Increased Alertness
Habit From Childhood
(Kristiansen, et al., 2005; Froiland, et al., 2004)
Many multivitamins marketed as performance vitamins include other herbal
supplements.
Athletes, trainers, coaches, and medical Professionals need to be aware of the
extra ingredients in the OTC (over the counter) multivitamins since
multivitamins are not subject to FDA regulation.
Iron
Women in general tend to have more iron deficiency issues
than men.
Possible causes of iron deficiency:
Underestimated Menstrual Blood Loss
Inadequate Dietary Intake
Increased Loss from Sweat
Gastrointestinal Blood Loss in Runners
Even slight anemia will negatively impact performance!
(Beard & Tobin , 2001; Nielsen & Nachtigall, 1998)
Iron Supplementation
Forms of Iron:
Different forms are absorbed differently
OTC products are unregulated
A Rx Multivitamin with Iron may be the appropriate route for a female
athlete with an iron deficiency.
Athletic Performance has not been improved by supplementing nonanemic athletes with iron
Side Effects of Supplementing with Normal Ferritin Levels:
Gastrointestinal Distress
Constipation
(Beard & Tobin , 2001; Nielsen & Nachtigall, 1998)
Calcium
Female athletes stated these reasons for taking calcium:
Strengthen Bones
Lactose Intolerance
Low Dietary Intake
Dietary protein should be monitored relative to calcium.
(Kristiansen, et al., 2005; Froiland, et al., 2004)
Calcium: Protein Ratio
Increased dietary protein may lower urinary pH and increase
calcium excretion (Barzel & Massey, 1998).
Increased calcium intake can offset the elevated calcium losses
(Dawson-hughes, 2003)
20:1 is the typical recommended ratio for a middle-aged
woman (Heaney, 1998).
An athlete’s need may be different due to an increased protein
consumption to maintain a positive nitrogen balance.
Use of the dietary journal is key to assess nutritional
consumption information.
Summary
Many times athletes do not understand supplements, regulations,
or how to read the labels on these supplements.
OTC supplements are unregulated by the FDA and the product
may be adulterated with products not listed on the label, some of
which may be banned by athletic governing bodies.
Athletes, coaches, trainers, and medical professionals should be
well versed on brands, supplements, and regulations before
recommending use of a product.
Always check the rules of your particular governing body for
legality of the supplement in question!