Chpt 1 PPT - Lecture notes 1 PDF

Preview

Summary

NTDT 310 Chpt 1...

Description

Chapter 1 Intro to Nutrition for Health, Fitness, and Sports Performance Introduction - Two major focal points of this book: - The role nutrition, complemented by physical activity and exercise, may play in determining one’s health status - The role nutrition may play in the promotion of fitness and sports performance Physical Fitness - A set of abilities an individual possesses to perform specific types of physical activity - 2 categories - Health related fitness: nutrition/PA - Sports related fitness: nutrition/PA Health Related Fitness - What is it? ** - Healthy body weight and composition - Cardiovascular - respiratory fitness - Adequate muscular strength and endurance - Sufficient flexibility - Other measures - Bp, bone strength, postural control and balance, indicators of lipid and carbohydrate metabolism Sports - Related Fitness - Fitness athletes develop specific to their sport - Strength - Power - Speed - Endurance - Neuromuscular motor skills - Compared to health related fitness, training for sports performance is often more intense, prolonged, and frequent Exercise and Health Promotion - Sedentary Death Syndrome (SeDs) (term coined by Frank Booth, University of Missouri) - Physical inactivity is a primary cause of most chronic diseases - Short term cost: - Metabolic deterioration and weight gain - Intermediate term cost: - Increased risk for disease, such as type 2 diabetes - Long term cost:

-

Increase rate for premature mortality

Physical Activity - Physical activity - any bodily movement caused by muscular contraction that results in energy expenditure - Unstructured physical activity - activities of daily living - Leisurely walking and cycling, climbing stairs, dancing, gardening, yard work, domestic and occupational activities and games - Structured physical activity - planned program of physical activities designed to improve fitness - Moderate to vigorous exercise such as brisk walking Health Benefits of Regular Physical Activity

Exercise and Health - Physical inactivity - Causes genes to misexpress proteins, producing unfavorable metabolic dysfunctions - Exercise - Causes expression of genes w/ favorable health effects

Cytokines - Exercise stimulates release of small proteins from muscle cells known as cytokines that influence gene expression - Muscle cells produce - myokines - Fat (adipose) cells produce - adipokines - Cytokines and heat shock proteins (HSPs, produced by muscle cells) may prevent chronic disease - Increase number of glucose receptors, improve insulin sensitivity, and help to regulate blood glucose and prevent type 2 diabetes Effect of Cytokines on Gene Regulation in Body Cells

Inflammation and Disease - Local inflammation - recognized as a risk for several chronic diseases - Exercise produces anti inflammatory cytokine to help cool inflammation and reduce health risks - Most marked improvements in the inflammatory profile are conferred with higher intensity exercise - Combined aerobic and resistance exercise training may provide greatest benefit Other Health Promoting Mechanisms - Loss of excess body fat - may reduce production of cytokines that may impair health - Loss of excess body fat - may reduce estrogen levels, reducing risk of breast cancer - Reduction of abdominal obesity - may decrease blood pressure and serum lipid levels - Increased mechanical stress on bone - with high impact exercise - may stimulate increases in bone density - Production of some cytokines such as brain derived neurotrophic factor (BDNF) may enhance neurogenesis and brain function

Components of Physical Activity Plans that Promote Health and Wellness - Aerobic exercise - Muscle strengthening exercise - Flexibility and balance exercises Guidelines for Aerobic Exercise - Adults - Moderate intensity aerobic: - 150 min/week or 30 mins for 5 days - Vigorous intensity exercise: - 75 mins/week - Or equivalent combo of each Aerobic Intensity - 1. Moderate physical activity - 40-59% of aerobic capacity - 5-6 on 10 point RPE scale (0=sitting, 10 max) - About 3-5.9 METs - Talk test- can talk, but not sing a few notes before taking a breath - Walking 2-3 mph or 20 min/mile - >100 steps/min Aerobic Intensity - 2. Vigorous physical activity - 60% or more of aerobic capacity - 7-8 on the RPE scale - METs > or equal to 6 - Talk test - difficult to talk in complete sentences - 130 steps/min - HIIT = high intensity interval training Examples of Moderate Intensity and Vigorous Intensity Aerobic Exercise

General Exercise Guidelines for Adults and Older Adults - Muscle strengthening (resistance exercise) - Do about 2-3 times/week - 8-10 exercises stress major muscle groups (legs, hips, back, chest stomach, shoulders, arms) - 8-12 repetitions of each exercise (weights, machines, or body resistance such as push ups or pull ups) - Flexibility and balance exercise - Perform activities that maintain or improve flexibility on at least 2 days a week for at least 10 mins daily - Perform exercises that help maintain or improve balance about 3x per week General Exercise Guidelines for Children and Adolescents - 60 mins or more daily - Aerobic - Most of 60 or more mins should be moderate or vigorous intensity aerobic exercise - Muscle strengthening - Part of 60 or more mins daily, muscle strengthening exercise at least 3 days/week

-

Bone strengthening - Part of 6o or more mins of bone strengthening exercise at least 3 days per week (hop scotch, tennis, basketball)

General Exercise Guidelines for Adults and Older Adults - More increases health benefits - Weekly aerobic physical activity - 300 mins of moderate (60 mins x 5 days) - 150 mins of vigorous exercise or an equivalent combo of both Are Americans Meeting Physical Activity Guidelines - No - 80% of adults/adolescents are not getting enough - Those living in the south are less likely to be active - Non hispanic white adults are more likely to meet guidelines Can Too Much Exercise Be Harmful To My Health - Some possible health problems associated w/ excessive or improper exercise - Orthopedic problems - Impaired immune functions - Exercise induced asthma - Exercise addiction - Osteoporosis - Heart illness and kidney failure - Brain damage - Heart attack and sudden death - Accidents Nutrition and Fitness - Nutrition - the sum total of processes involved in the intake and utilization of food substances by living organisms, including ingestion, digestion, absorption, transport, and metabolism of nutrients in food Six Major Classes of Essential Nutrients - Carbohydrates (macronutrients) - Fats or lipids (macronutrients) - Proteins (macronutrient) - Vitamins (micronutrient) - Minerals (micronutrient) - Water Basic Function of Food - Promote growth and development

-

Provide energy** Regulate metabolism

Nutrients - Specific substance in food performs 1 or more physiological or biochemical functions in body - Similar to cytokines - May influence gene expression +/- effects on health - Certain amounts of vit/min may prevent damage to DNA, while excessive alcohol may damage - Most chronic disease have genetic basis - 3 stages Role of Nutrition in Health Promotion - 3 stages of disease progression - Initiation → promotion → progression - Genetic predisposition - Environmental factors - Food is medicine - 2 roles of nutrients: - Promoters - lead to progression of chronic disease - Antipromoters - deter initiation of progression of chronic diseases Health Problems Associated With Poor Dietary Habits

Do Most Americans Eat Right? - On average, Americans of all ages consume: - Too few: - Veggies - Fruits - High fiber whole grains - Low fat milk products - Seafood - Too much: - Added sugar - Solid fat - Refined grains - Sodium What Are Some General Guidelines for Healthy Eating? - 1. Dietary Guidelines for Americans - Every 5 years; current 2015 to 2020 - 2. Healthy People 2020 - 10+ year goal - 3. USDA MyPlate - Recommendations Prudent Healthy Diet (1) - Academy of Nutrition and Dietetics and the various governmental and professional health organizations - 12 guidelines 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 - Pre diabetes - Heart disease - Cancer - Neurological and cognitive disorders Pre-Diabetes - Excess body weight - Impaired fasting blood glucose - Glucose intolerance - Increase risk of type 2 diabetes

-

Prevention: - Diet, aerobic training, resistance training

Heart Disease - Key lifestyle behaviors effective for modifying risk factors: - Proper nutrition - Exercise Cancer - American Institute of Cancer Research: - 3 means for prevention - 1. Choose mainly plant based foods, limit 3 meat, avoid process meat - 2. Be physically active in any way for 30 min every day - 3. Aim to be healthy weight throughout most of life Sports Related Fitness: Exercise and Nutrition - What makes a sport champion - Nature (Genes/hardware) and nurture (Environment/software) are both essential ingredients for superior performance in a given sport What is Sports Related Fitness - Athletes develop sports related fitness by training for a specific sport: - Strength and power in football, bobsled, and shot put - Endurance in long distance cycling, running, or swimming - Neuromuscular skills in gymnastics, archery, and cross country skiing in the biathlon event What is Sports Nutrition? - The application of nutritional principles to enhance sports performance - 1. To promote good health - 2. To promote adaptations to training - 3. To recover quickly after each training session - 4. To perform optimally during competition Are Athletes Receiving Adequate Nutrition? - Results of dietary surveys are mixed - General findings: - Inadequate amounts of energy, particularly carbohydrates - Athletes consume more dietary fat than recommended, particularly saturated fat - Intake of vitamins and minerals varies - Athletes who restrict energy intake may be at high risk for micronutrient deficiencies - Iron and calcium deficiencies may be common in female athletes

-

Many athletes take dietary supplements designed to enhance performance

Why are Some Athletes Malnourished? - Insufficient knowledge to make appropriate food choices - Misconceptions about the roles of specific nutrients in sports performance - May not be getting sound sports nutrition info - Websites and poorly informed coaches - Time limitations for food prep - Financial constraints Roles of Diet and Nutrients During Exercise

How Does Nutrition Affect Athletic Performance? - Role of nutrients - Provide energy - Regulate metabolic processes - Support growth and development - Malnutrition - Undernutrition - Overnutrition What Should Athletes Eat to Optimize Sports Performance? - Depends on variety of factors - Gender - Age

-

- Body weight status - Eating and lifestyle patterns - Environment - Type of sport or event Varying viewpoints: - Athletes need a nutritionally balanced diet- no special recommendations are needed - It is almost impossible to obtain all the nutrients the athlete requires from the normal daily intake of food - nutrient supplementation is absolutely necessary - Others advocate a compromise

What Am I? - Ergogenic Aid - Defined as a means to increase potential for work output - Performance enhancing techniques - mechanical and psychological aids - Performance enhancing substances - physiological, pharmacological, and nutritional aids - *external influence that may enhance training, performance, recovery - Not necessarily FDA approved ** 5 Classes of Ergogenic Aids - 1. Mechanical aids - Designed to increase energy efficiency - Ex. lighter racing shoe, less energy to move legs - 2. Psychological aids - Increase mental strength - Ex. hypnosis - 3. Nutritional aids - Nutrients designed to influence physiological/psychological processes - Ex. protein supplements - 4. Physiological aids - Designed to increase natural body processes to increase physical power - Ex. blood doping - infusion of blood into an athlete - may increase O2 transport capacity, increasing aerobic endurance - 5. Pharmacological aids - Drugs designed to influence body, mind processes - Ex. AAS, deer antler velvet spray (IGF1), caffeine Why are Nutritional Ergogenics so Popular? - Dietary sports supplements: - Powders, pills, and ready to drink products - Nutrition bars and gels - Sports and energy drinks and shots

-

Popularity: - Belief in magical qualities of some supplements - Shrewd advertising and marketing, endorsements by professional athletes - Recommended by coaches and fellow athletes - Belief that sports supplements are natural, safe, and legal

Ask These Questions When Evaluating Ergogenics? - Is it effective? - Is it safe? - Is it legal? Are Nutritional Ergogenics Effective? - Research suggests a few are but most not - Supplements are found in each nutrient class (CHO, PRO, FAT, VIT/min, H2O) - Supplementation above/beyond the RDA is not necessary for the vast majority of well nourished athletes - Consumption of specific nutrients above the RDA has not been shown to exert any ergogenic effect on human physical or athletic performance - Sold on the market with various performance - enhancement claims without specific evidence Are Nutritional Ergogenics Safe? - Majority of over the counter dietary supplements are safe when taken as directed - Potential problems: - Contain chemicals linked to serious illnesses and death, particularly when taken in excess - Mislabeled and contain unlisted substances like stimulants or steroids - Younger athletes may think that “if one is good, then ten is better”, leading to overdose Are Nutritional Ergogenics Legal? - Use of pharmaceutical agents to enhance performance in sport has been prohibited by the governing bodies of most organized sports (doping) - Some dietary supplements are prohibited: - Anabolic steroids such as androstenedione - Stimulants such as ephedrine - Contaminations of sports supplements that may cause an athlete to fail doping test is widespread - Up to 25% of sports supplements target for muscle building and marketed on the internet were contaminated with prohibited substances US Anti-Doping Agency - “Nutritional or dietary supplements is completely at the athlete’s own risk”

Dietary Supplement Health and Education Act (DSHEA) of 1994 - Manufacturing firm responsible for: - 1. Determining dietary supplements it makes/distributes are safe - 2. That any representations/claims made about supplements are substantiated by adequate evidence to show they are not false/misleading FDA Does Not Need To Approval - Dietary supplements do not need approval from FDA before they are marketed (except in the case of a new dietary ingredient) - FDA has to take on burden to prove false Nutritional Quackery in Health and Sports - Increasing numbers of dietary supplements are marketed to enhance health and physical performance - Unfortunately, many of the products have no legitimate basis What is Nutritional Quackery - Quackery - Fake practitioner - Worthless product - Untrue or misleading claims that are deliberately or fraudulently made for any product - Health quackery is a big business - Americans spend almost $27 billion annually on questionable health practices Why is Nutritional Quackery so Prevalent in Athletics - As with nutritional quackery in general, hope and fear are the motivating factors underlying the use of nutritional supplements by athletes - Attempts to gain a competitive edge - Possible factors promoting quackery in sports: - Endorsements by star athletes - Misinformation in sports magazines or books How Do I Recognize Nutritional Quackery in Health and Sports? - Some questions to ask about products - Does it promise quick improvement in health or performance? - 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 Info to Combat Quackery in Health and Sports? - Key resources - Reputable books (check author’s credentials) - Government, health professionals, consumer, and commercial organizations and related websites (.gov, .edu, .org) - Scientific journals - database - Popular magazines (check credentials) - Consultants: The Academy of Nutrition and Dietetics - SCAN: certified specialists in sports Cautions On Using the Internet - The US Department of Health and Human Services has recommended caution in using the internet to find health info - Along with others, here are some of its major points - No one regulates info on the internet - Websites like Wikipedia permit anyone to enter or modify the info presented - Search engines, like Google and Yahoo, host paid advertisements that may contain biased information - Compare the info you find with other resources - Check’s the author’s organization credentials - Be wary of websites advertising and selling products that claim to improve health - Be cautious when using info found on boards - Don’t believe everything you read Research and Prudent Recommendations - Evidence based recommendations - Show the science! What Types of Research Provide Valid Information? - Epidemiological research (observational research) - study large population to find relationships between 2 variables - Ex. dietary fat 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 - Helps scientists identify important relationships between nutritional and practices and health - Dietary fat and heart disease

-

* does not prove a cause and effect relationship

Experimental Research - Essential to establishing a cause and effect relationship - Randomized clinical trials (RCTs) or intervention studies - Usually involve a treatment group and a control (placebo) group - Cause and effect - Independent variable - cause (diet) - Dependent variable - effect (heart disease) Research on Effect of Nutrition on Sports Performance - Most laboratory studies - Tight control of extraneous variables - Mimic the physiological demands of a specific sport - Few studies have actually investigated the effect of nutritional strategies on actual competitive sports performance* Why Do We Often Hear Contradictory Advice About the Effects of Nutrition on Health or Physical Performance? - Difficult to conduct nutritional research about health and athletic performance w/ human subjects - Unknown extraneous factors may lead to erroneous conclusion - Media exaggeration or oversimplification - Consider: - Quality and credibility of the study - Peer reviewed study or presentation at a meeting - Comparison of findings to other studies - Findings put in proper context - Funding sources Well Designed Experimental Research - Methodological considerations for lab studies - Logical rationale - legit reason? Purpose? Why? - Appropriate subjects - strength trained for power perform - Valid performance tests - strength tests, 100m run, ergometer - Placebo control - similar taste, color - Random assignment of subjects - repeated meas./crossover - Double blind protocol - neither subjects nor investigator know - Control of extraneous factors - those influence outcome - Appropriate data analysis (statistics) - SPSS, Anova, sample size, competing interest, funding What is the Basis for the Dietary Recommendations Presented in this Book?

-

-
<...