Chapter 1
Lecture Slides
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Introduction
• Two main focal points of this text
– The role nutrition, complemented by physical
activity and exercise, may play in determining
one’s health status
– The role nutrition may play in the enhancement of
fitness and sports performance
Health Status
• Genetics and Lifestyle
• Six of ten leading causes of death
– 80 percent of all deaths
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Diseases of the heart
Cancer
Stroke
Chronic lung diseases
Diabetes
Chronic liver diseases and cirrhosis
• Preventable
Genetics and Lifestyle
• Genetics
– May account for 30 percent of life expectancy
• Lifestyle choices and environmental factors
– Diet
– Physical activity
– Medicine
Risk Factors
• A health behavior associated with a given
disease
– Family history
– Cigarette smoking
– Excessive alcohol consumption
– Poor dietary habits
– Physical inactivity
• Nutrigenomics and exercisenomics
Cool Website
www.hhs.gov/familyhistory
Create your own family health history.
Sport and Exercise Performance
• Genetics
– Stature
– Body composition
– VO2max
– Vision
• Training
– Optimal physiological,
psychological and
biomechanical training
Physical Fitness
• A set of abilities an individual possesses to
perform specific types of physical activity
– Sports-related fitness
– Health-related fitness
What Is Health-Related Fitness?
Health related fitness
– Healthy body weight and body composition
– Cardio-respiratory fitness
– Adequate muscular strength and endurance
– Adequate flexibility
– Other measures
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Blood pressure
Bone strength
Postural control and balance
Markers of carbohydrate and lipid metabolism
Physical Activity
• General definition of physical activity is any
movement caused by muscle contraction that
results in caloric expenditure
• Unstructured physical activity
– Activities of Daily Living (ADL)
• Leisurely walking
• Structured physical activity
– Planned exercise programs
• Brisk, aerobic walking
What are the basic principles of
exercise training
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Principle of overload
Principle of progression
Principle of specificity
Principle of recuperation
Principle of individuality
Principle of reversibility
Principle of overuse
Principle of Overload
• Intensity of exercise
– % of heart rate or maximal oxygen uptake
– % or repetition maximal (RM)
• Duration of exercise
– Time of exercise session
• Frequency of exercise
– Number of sessions per week
Principle of Progression
• Gradual increase in overload with training
– Faster speed of running
– More weight lifted
Principle of Specificity
• Hans Selye SAID principle
• Specific Adaptations to Imposed Demands
– Endurance training
• Running
• Cycling
• Swimming
– Strength training
• Muscular strength, power and muscle mass
• Muscular endurance
Principle of Recuperation
• Recovery and rest
– Within exercise session
– Between exercise sessions
Principle of Individuality
• Individual responses to exercise training
– Blood pressure
• Responders – Blood pressure is lowered
• Nonresponders – No change in blood pressure
Principle of Reversibility
• Use it or lose it
– Health gains gradually disappear in detraining
• Single exercise bouts
– May induce beneficial effects
• Lowered blood pressure
• Decreased blood sugar response
• Chronic exercise training
– Needed to maximize health benefits
Principle of Overuse
• Excessive exercise may induce adverse health
effects
– Muscle injuries
– Stress fractures
What is the role of exercise in
health promotion?
• Sedentary Death Syndrome (SeDS)
– Health problems with physical inactivity
– Frank Booth – University of Missouri
• Short-term costs
– Metabolic deterioration and weight gain
• Intermediate-term costs
– Type 2 diabetes
• Long-term costs
– Increased rate of premature mortality
What is the role of exercise in
health promotion?
• Physical inactivity
– 45% increased risk of coronary artery disease
– 60% increased risk of stroke
– 30% increased risk of hypertension
– 59% increased risk of osteoporosis
U. S. Centers for Disease Control and Prevention
Health Benefits of Exercise
Health Benefits of Exercise
• Prevent predisease conditions
– Increased body weight (abdominal fat)
– Elevated blood glucose
– Type 2 diabetes
• Diabesity
• Type 2 diabetes
– 171 million worldwide in 2000
– 366 million worldwide in 2030 (projection)
How does exercise enhance health?
• Specific mechanisms not completely
understood
• Physical inactivity
– Impaired gene function
– Cytokines may induce gene expression
• Fewer glucose receptors in fat cells
• Exercise may cause the expression of genes
with favorable health effects
– Cytokines induce beneficial gene expression
• More glucose receptors in fat cells
How does exercise enhance health?
• Local inflammation recognized as a risk factor
for major chronic diseases
• Exercise produces an anti-inflammatory
cytokine to help cool inflammation
• Some healthful adaptations with a single bout
of exercise
– Improved blood lipid profile
– Reduced blood pressure
– Improved insulin sensitivity
Do most of us exercise enough?
• In general, NO.
• Most adults are not getting enough physical
activity
• About 40-50% of college students are
physically inactive
• Children and adolescents more physically
active, but many not obtaining adequate
amounts
– Increased type 2 diabetes in children related to
physical inactivity
How much physical activity is enough
for health benefits?
How much physical activity is enough
for health benefits?
• Comprehensive program of physical activity
– Aerobic exercise
– Resistance exercise
– Flexibility exercise
Moderate and vigorous
physical activity
• Moderate physical activity
– 40-50% of aerobic capacity
• Heart rate monitoring (Chapter 11)
– 5-6 on 10-point RPE scale
– Talk test – carry on a conversation
• Vigorous physical activity
– 60% or more of aerobic capacity
– 7-8 on the RPE scale
– Talk test – difficult to talk in complete sentences
What are some general guidelines for exercise
programs for someone who wants to become
more physically active?
Recent Guidelines
• American College of Sports Medicine and the
American Heart Association (2007)
– www.acsm.org/physicalactivity
• Department of Health and Human Services
(2008)
– http://www.health.gov/paguidelines
General Exercise Guidelines
for Adults and Older Adults
• Aerobic exercise
– 30 minutes of moderate-intensity 5 days a week
or
– 20 minutes of vigorous-intensity 3 days a week
or
– 2 days of moderate and 2 days of vigorous
– May be done as exercise snacks
• 3 bouts of 10 minutes (total 30 minutes)
General Exercise Guidelines
for Adults and Older Adults
• Resistance exercise
– 8-10 exercises that stress the major muscle
groups of the body
– 8-12 repetitions of each exercise at least twice a
week on nonconsecutive days
– May use weights, machines, or body resistance
such as push-ups and pull-ups
General Exercise Guidelines
for Adults and Older Adults
• Flexibility and balance exercise
– Older adults should perform activities that
maintain or improve flexibility on at least 2 days a
w3ek for at least 10 minutes daily
– Older adults should also perform exercises that
help maintain or improve balance about 3 times a
week
General Exercise Guidelines
for Adults and Older Adults
• Individualization
– Exercise programs, especially for older adults,
should be individualized based on physical fitness
and health status
– One key component is simply to reduce the
amount of daily sedentary activity.
– Leisurely walking may be adequate physical
activity for elderly individuals or those with
compromised health status
General Exercise Guidelines
for Adults and Older Adults
• More is Better
– For substantial health benefits, adults should do
at least 150 minutes of moderate intensity, or 75
minutes of vigorous intensity aerobic physical
activity, or an equivalent combination of
moderate and vigorous per week
– For additional and more extensive health benefits,
adults should increase their weekly aerobic
physical activity to 300 minutes of moderate or
150 minutes of vigorous, or an equivalent
combination
One model of the Physical Activity Pyramid
• Level I: 30 minutes daily: low-intensity
• Level II: 3-5 days/week, > 30 minutes of
moderate, 20 minutes of vigorous, or
combination of moderate and vigorous
• Level III: 3-7 days/week stretching to fitness
• Level IV: 2-3 days/week resistance activities
• Level V: Limit physical inactivity (e.g. TV
watching
General Exercise Guidelines
for Children and Adolescents
• Should do 60 minutes or more of physical
activity daily
– Most of the 60 or more minutes should be either
moderate or vigorous intensity aerobic exercise
– As part of their 60 or more minutes daily, musclestrengthening exercises should be performed on
at least 3 days per week
– As part of their 60 or more minutes daily, bonestrengthening exercises should be performed on
at least 3 days per week
General Exercise Guidelines
for Children and Adolescents
• It is important to encourage young people to
participate in physical activities that are
appropriate for their age, that are enjoyable,
and that offer variety.
2008 Physical Activity Guidelines for Americans
Cool Websites
• www.smallstep.gov
• www.Americaonthemove.org
• www.fitness.gov
• Consult these Websites for information on
fitness and starting an exercise program for
most individuals.
www.choosetomove.org
• Choose to Move is a free, 12-week physical
activity program for women developed by the
American Heart Association.
Cool Websites
www.Kidnetic.com
www.nick.com/myworld/letsjustplay
www.whatmovesu.com
www.verbnow.com
• These Websites provide games and activities to
help children become more physically active and
promote overall good health. The What Moves U
Website was developed jointly by the National
Football League and American Heart Association,
and has activity kits for use by school teachers.
Can too much exercise be harmful to
my health?
• Some possible health problems associated
with excessive or improper exercise
– Orthopedic problems
– Impaired immune function
– Exercise-induced asthma
– Osteoporosis
– Heat illness and kidney failure
– Heart attack
Nutrition and Health-Related
Fitness
• Overall definition of nutrition: Sum total of
processes involved in intake and utilization of
food substances by living organisms, including
ingestion, digestion, absorption, transport,
and metabolism of nutrients in food
Six Classes of Nutrients
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Carbohydrates (Macronutrient)
Fats or Lipids (Macronutrient)
Proteins (Macronutrient)
Vitamins (Micronutrient)
Minerals (Micronutrient)
Water
Major functions of nutrients In food
What is the role of nutrition in
health promotion?
• Food is Medicine
– Hippocrates: Let food be your medicine and
medicine be your food.
• Role of nutrients
– Promoters: Lead to progression of chronic diseases
– Antipromoters: Deter initiation or progression of
chronic diseases
• Healthful nutrition reduces the risk of
numerous chronic diseases
Proposed health roles of nutrients
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Inactivate carcinogens or kill bacteria that cause cancer
Increase insulin sensitivity
Relax blood vessels and improve blood flow
Reduce blood pressure
Optimize serum lipid levels
Reduce inflammation
Inhibit blood clotting
Enhance immune system functions
Speed up digestive processes
Prevent damaging oxidative processes
Reduce body fat
Do we eat right?
• As a nation, we eat
– Too many Calories
– Too much fat and saturated fat
– Too much sugar and other sweeteners
– Too much salt
– Too much meat and cheese
– Too few fruits and vegetables
– Too few fiber-rich foods
– In general, more than we need and less of what
we need more
What are some general guidelines for
healthy eating?
• Nutrition and Your Health: Dietary Guidelines
for Americans
– Every 5 years. Current, 2005.
• Health Professional Organizations
– American Heart Association
– American Cancer Society
– American Diabetes Association
What are some general guidelines for
healthy eating?
• Examples of recommended diets
– Mediterranean diet
– Harvard Healthy Eating Diet plan
– Optimal Macronutrient Intake diet plan
• OmniHeart Diet
– Dietary Approaches to Stop Hypertension diet
• DASH diet
The Prudent Healthy Diet
• Based on current recommendations from
major health professional organizations and
government health agencies.
The Prudent Healthy Diet
1. Balance the food you eat with physical
activity to maintain or improve your weight.
The Prudent Healthy Diet
2. Eat a nutritionally adequate diet consisting of
a wide variety of nutrient-rich foods.
The Prudent Healthy Diet
3. Choose a diet moderate in total fat, but low in
saturated and trans fat and cholesterol.
The Prudent Healthy Diet
4. Choose a diet with plenty of fruits and
vegetables, whole grain products, and
legumes.
The Prudent Healthy Diet
• 5. Choose beverages and foods that moderate
or reduce your intake of sugars.
The Prudent Healthy Diet
• 6. Choose and prepare foods with less salt and
sodium.
The Prudent Healthy Diet
• 7. If you drink alcoholic beverages, do so in
moderation.
The Prudent Healthy Diet
• 8. Maintain protein intake at a moderate, yet
adequate level, obtaining much of your daily
protein from plant sources, complemented by
smaller amounts of fish, skinless poultry and
lean meat.
The Prudent Healthy Diet
• 9. Choose a diet adequate in calcium and iron.
Individuals susceptible to tooth decay should
obtain adequate fluoride.
The Prudent Healthy Diet
• 10. Practice food safety, including proper food
storage, preservation and preparation.
The Prudent Healthy Diet
• 11. Avoid excess intake of questionable food
additives and dietary supplements.
The Prudent Healthy Diet
• 12. Enjoy your food. Eat what you like but
balance it within your overall healthful diet.
Am I eating right?
• Take the quiz in the Application Exercises
section at the end of this chapter to rate your
current diet.
• You may also obtain a detailed analysis of
your diet, and physical activity, by accessing
the MyTracker link on www.MyPyramid.gov.
Are there additional health benefits when both
exercise and diet habits are improved?
• A poor diet and physical inactivity are
individual risk factors for a number of chronic
diseases. Collectively they may pose
additional risks.
• A healthy diet and increased physical activity
may exert complementary effects to help
prevent several chronic diseases.
– Diabetes
– Heart disease
– Cancer
Sports-Related Fitness:
Exercise and Nutrition
• What makes a champion?
– Genetics
• Genetic factors determine 20 to 80 percent of the
variation in a wide variety of traits relevant to athletic
performance
– Training
• Optimal training can maximize an athlete’s genetic
potential
– Nutrition
• Some specific nutritional practices may benefit athletes
Sports-related fitness
Sports-related fitness:
• Strength
• Power
• Speed
• Endurance
• Sport-specific neuromuscular motor skills
Sports-related fitness:
Energy demands and control
• Explosive power sports
– Olympic weight lifting
• Very high-intensity sports
– 100-meter dash
• High-intensity, short duration sports
– 5,000-meter run
• Intermittent high-intensity sports
– Soccer
Sports-related fitness:
Energy demands and control
• Endurance sports
– Marathon running (26.2 miles; 42.2 kilometers)
• Low-endurance, precision skill sports
– Golf
• Weight-control and body-image sports
– Bodybuilding
Sports fitness
• Training of elite athletes: United States
Olympic Training Center
– Physical power
• Physiological energy systems
– Mental strength
• Psychological processes
– Mechanical edge
• Biomechanical skills
What is sports nutrition?
• The application of nutritional principles to
enhance sports performance.
– To promote good health
– To promote adaptations to training
– To recover quickly after each training session
– To perform optimally during competition
Louise Burke, Australian Institute of Sport
Is sports nutrition a profession?
• Professional associations
– SCAN, American Dietetic Association
– International Society of Sports Nutrition
• Certification programs
– Specialty in Sports Dietetics (SCAN)
• Research productivity
– International Journal of Sport Nutrition (1991)
• Consensus statements and position stands
– Nutrition and athletic performance
(ACSM,ADA,DC)
Are athletes today receiving adequate
nutrition?
• Dietary survey research
– Underreporting
– Nutrient intake versus clinical deficiency
• Individual variability
• Weight-control sports
– Eating disorders
• Young athletes
• Athletes not meeting recommendations
• Source of nutrition information
How does nutrition affect athletic
performance?
• Role of nutrients
– Provide energy
– Regulate metabolic processes
– Promote growth and development
• Malnutrition
– Undernutrition
– Overnutrition
What should athletes eat to help optimize
sports performance?
• Depends on a variety of factors
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Gender
Age
Body weight status
Eating and lifestyle patterns
Climatic conditions
Type of sport and training
• Viewpoints
– Nutrient supplements are needed by all athletes
– No athlete needs nutrient supplements
– Some athletes may benefit from nutrient supplements
Ergogenic Aids and Sports Performance
• Genetics
• Training
• Ergogenic aids – Beyond training
What is an ergogenic aid?
• Ergogenic
– Defined as a means to increase potential for work output
– Performance-enhancing techniques
– Performance-enhancing substances
• Classes of ergogenic aids
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Mechanical aids
Psychological aids
Physiological aids
Pharmacological aids
Nutritional aids
Why are nutritional ergogenics so popular?
• Use of drugs is illegal
– Doping
– World Anti-Doping Agency (WADA)
• Dietary supplements
– Sports supplements
• Popularity
– Belief in magical properties of some supplements
– Recommended by coaches and fellow athletes
– Shrewd advertising and marketing
• Endorsement by star athletes
Are nutritional ergogenics effective?
• Research suggests a few are but most are not
• Supplements are found in each nutrient class
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Carbohydrates: Specific forms such as ribose
Fats: Specific fatty acids such as omega-3
Protein: Specific nitrogen compounds such as creatine
Vitamins: Specific vitamins such as B12
Minerals: Specific minerals such as phosphate salts
Water: Special oxygenated waters
Others: Food drugs like caffeine and herbals like ginseng
Are nutritional ergogenics safe?
• Most over-the-counter (OTC) dietary supplements
are safe taken as directed
• Potential problems
– Product may not contain substances as per the
Supplement Facts label
– Athletes may use the concept “If one is good, ten
is better”
• Young athletes
Are nutritional ergogenics legal?
• Legality or permissibility in sports (Doping)
• Some dietary supplements banned in sports
– Anabolics such as androstenedione
– Stimulants such as ephedrine
• Intentional or inadvertent contamination
– Intentional inclusion of banned substance
– Processed in factory that produces banned substances
Nutritional Quackery in Health and Sports
• Thousands of foods and supplements marketed to
enhance health and physical performance
What is nutritional quackery?
• Misinformation
– Promotion of worthless product
– Glitzy brochures; Infomercials
• Supplements are big business
– Estimated $25 billion annual sales
• To be discussed in chapter 2
– Dietary Supplements Health and Education Act
– Supplement Facts label
• Statement to the effect that the FDA has not evaluated the
effectiveness of this product
Why is nutritional quackery so prevalent in
athletics?
• Attempts to gain a competitive edge
• Possible factors promoting quackery in sports
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Eating behaviors of star athletes
Advice from coaches
Misinformation in sports magazines and books
Direct advertising to the athlete
Cool Website
www.supplementwatch.com
• Click on Product Review, and then Sports & Fitness.
Provides a review of specific sports supplements.
How do I recognize nutritional quackery in
health and sports?
• Some questions to ask about products:
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Does it promise quick improvement in health or sports?
Does it contain some magical ingredient or formula?
Is it marketed by popular personalities or sports stars?
Does it exaggerate a single truth about an ingredient?
Does it question the integrity of the scientific or medical
establishment?
– Does the person or magazine who recommends it also sell
it?
– Is its claim too good to be true?
Where can I get sound nutritional information
to combat quackery in health and sports?
• High quality research
– Scientific books
– Government, professional, educational, consumer groups
• Websites: .gov; .edu; org; use caution with .com sites
– Scientific journals
– Popular magazines
– Consultants
• American Dietetic Association (www.eatright.org)
– SCAN: Certified Specialist in Sports Nutrition (CSSD)
Research and Prudent Recommendations
• Research in the past
– Identify nutrients in foods
– Determine functions of specific nutrients
• Current research with foods and nutrients
– Health benefits
– Performance-enhancing effects
• Evidence-based recommendations
– Data base
– Nature of research and possible limitations
What types of research provide valid
information?
• Epidemiological research (Observational research)
– Study large populations to find relationships between two
variables, for example diet and heart disease
– Retrospective techniques
• Compare diets of those with heart disease to a similar group
(cohort) of those without heart disease
– Prospective techniques
• Diets of individuals without heart disease are studied for years and
then related to those who do and do not develop heart disease
Epidemiological research
• Epidemiological research
– Helps scientists identify important relationships between
diet and health
• 1950s research – Dietary fat
– Does not determine cause and effect relationship
– Causality may be inferred if relationship is very strong
• Relative risk (RR) or odds ratio (OR)
• RR of 1.0 is normal probability; 2.0 is twice and 0.5 is half
Experimental research
• Experimental research
– Essential to establishing a cause and effect relationship
– Randomized controlled trials (RCTs)
– Cause and effect
• Independent variable – cause (Diet)
• Dependent variable – effect (Heart disease)
Experimental research
• Experimental research
– Populations
• Small groups (University laboratory research)
• Large groups (National or International studies)
– Conditions
• Randomization of subjects
– Matching of subjects
• Control or placebo condition
• Double blind procedure
– Gold standard
• RCTs with large populations
Experimental research and sports
performance
• Mostly laboratory studies; some designed to mimic
actual sports performance. However, few studies
with actual competition.
Experimental research:
Supplements and sports performance
• Methodological considerations for laboratory studies
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Logical rationale
Appropriate subjects
Valid performance tests
Placebo control (Note nocebo effect)
Random assignment of subjects
• Matched subjects
• Crossover design
– Double-blind protocol
– Control of extraneous factors
– Appropriate data analysis (statistics)
Why do we often hear contradictory advice about the
effects of nutrition on health or physical performance?
• Media exaggeration or oversimplification
• Quality of the study
– Limited number of subjects in RCT
• Peer-reviewed or presentation at a conference
• Funding sources
• Findings put in proper context
What is the basis for the dietary
recommendations presented in this book?
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Evidence-based research
Individual studies
Reviews of RCTs and epidemiological studies
Meta-analyses of RCTs
Position statements and position stands
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American College of Sports Medicine
American Dietetic Association
American Institute of Cancer Research’
American Heart Association
• Prudent recommendations
How does all this relate to me?
• Individuality
• Responders and non-responders
– Salt sensitivity
– Carbohydrates and gastrointestinal distress
• Seek appropriate guidance for supplements or other
nutritional strategies for medical applications or
performance enhancement strategies
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