Introduction to Nutrition for Fitness and Sports

Overall Health Status

l Dependent on 2 primary factors:

– Genetics

l Human Genome Project (HGP) currently being conducted to decipher DNA code to define genes of chronic diseases

– Lifestyle

l Diet and exercise are still important determinants of health

– Certain nutrients may be determined from HGP that are important for health

– Exercise may induce certain chemical changes important for health

Lifestyle Approaches

l Dr. James Rippe coined term “Lifestyle Medicine” in new book

l Healthy People 2010

– Reports designed to promote health and reduce risk of chronic diseases

– May be attained through www.health.gov/healthypeople

l Study of risk factors through epidemiology

Risk Factors to Health

l Smoking (current or quit within last 6 months)

l Hypertension (SBP > 140 mmHg or DBP > 90 mmHg on 2 separate occasions or on BP medication)

l Hypercholesterolemia (> 200 mg/dl or HDL-C of < 35 mg/dl or LDL-C of >130 mg/dl or on lipid lowering medication)

l Sedentary lifestyle (no regular exercise)

l Obesity (>30 kg/m² or waist girth >100 cm)

l Family history (heart problems in father < 55 years of age or in mother < 65 years of age

l Impaired fasting glucose (>110mg/dl on 2 separate occasions)

Physical Fitness

l 2 Categories:

– Health-related fitness

l A healthy body maintained through exercise and proper diet

– Sports-related fitness

l A healthy body capable of performing at high level of physical and mental state

Physical Fitness

l Health-related fitness

– Components:

l Cardiovascular-respiratory fitness

l Muscular strength

l Muscular endurance

l Flexibility

l Body composition

Physical Activity

l Movement of the body

– Classified as:

l Unstructured physical activity

– Daily activities of a normal day, i.e. leisure walking, cycling, gardening, etc.

l Structured physical activity

– Planned program of physical activity usually defined as “exercise”, i.e. running 3 times/week for 20 minutes/session

Role of Exercise in Health

l Prevents and reduces cardiovascular disease

l Prevents cancer, particularly colon cancer

l Building bone and prevents osteoporosis

l Lower triglycerides and raises HDL-C

l Prevents weight gain and helps maintain weight loss

Role of Exercise in Health

l Prevents obesity and controls risk factors

l Improves health-related fitness in older individuals

l Prevents Type II diabetes

l Improves life quality of HIV-infected

l Prevents and treats high blood pressure

l Improves psychological well-being

Role of Exercise in Health

l Improves quality of life

l Improves fitness in pregnant women

l Can increase life span by up to 2 years (according to Paffenbarger)

Do most Americans exercise enough to achieve the health benefits?

l No, not at this time

– 28% of adults participate in regular exercise

– 60% of adolescents participate in regular exercise

l Physical activity decreases with age

Health-related guideline for exercise

l 30 minutes of moderate exercise per day; longer durations are likely to derive a greater health benefit in most cases

l Corbin and Pangrazi designed the Physical Activity Pyramid to serve as a guide

Physical Activity Pyramid

Nutrition and Health-related Fitness

l Nutrition

– The sum total of the processes involved in the intake and utilization of food substances by living organisms

l Nutrient

– Specific substances found in food that perform one or more physiological or biochemical functions in the body

Nutrients

l 6 Major Classes of Nutrients:

– Carbohydrates

– Fats

– Proteins

– Vitamins

– Minerals

– Water

Function of Major Nutrients

l Provide energy for human metabolism

– Carbohydrates and fats are primary sources

l Promote growth and development by building and repairing body tissue

– Protein and minerals are primary sources

l Regulate metabolism, or body processes

– Vitamins, minerals, protein, and water are primary sources

Role of Nutrition in Health

l Fruits and vegetables

– Reduce cataracts

– Reduce lung and colon cancer

l Dietary fiber

– Reduces heart disease

– Reduces colon cancer

l Carotenoids

– Reduce prostate cancer

l Calcium

– Reduces incidence of osteoporosis

Role of Nutrition in Health

l Excessive amounts of certain nutrients can be deleterious

– Alcohol

l Increase in breast cancer, oral and esophageal cancer

l Increase in blood pressure, obesity

l Increase in liver disease

– Fats

l Increase in obesity

l Increase in breast cancer, colon cancer, prostate cancer

l Increase in heart disease

Do we eat right?

l No

l Most Americans consume too many calories and eat less of the food that they should consume

Guidelines for Healthy Eating

l Eat a nutritionally adequate diet

l Choose diet low in saturated fats & cholesterol

l Choose a diet that includes whole grain products and fiber

l Choose low sugar foods and beverages

l Consume foods with less salt

l Alcohol consumption should only be in moderation

Guidelines for Healthy Eating

l Protein intake should be moderate (1 gram/kilogram of body weight)

l Have adequate calcium and iron in diet

l Avoid food additives and dietary supplements

l Balance food intake with physical activity to maintain proper weight

l Enjoy your food

Are you eating right?

l Complete diet quiz in your book (pp 29-31)

l Will discuss briefly at next class

Nutrition + Exercise

l Together, these factors are more effective in helping enhance health-related fitness

l No study has:

– Shown how 1 good health behavior may affect others

– Shown degree of effectiveness for 1 good health behavior within a combination of good lifestyle behaviors

Sports-related Fitness

l An enhanced level of health that allows an individual to compete in sports.

Sports-related Fitness

l Components:

– Strength

– Power

– Speed

– Endurance

– Neuromuscular motor skills specific to a sport

Sports-related Fitness

l Training elite athletes focuses on 3 specific attributes

– Physical power

l Enhancement of physical abilities

– Mental strength

l Dealing with psychological demands

– Mechanical edge

l Performing efficiently via biomechanics, sports equip, etc.

Sport Nutrition

l The application of nutritional principles to sport, such that there is:

– Application of eating strategies to promote good health and adaptation to training

– Quicker recovery after exercise training sessions

– Optimal performance during competition

Are athletes getting adequate nutrition?

l In most cases, no!

– Athletes involved in weight-controlled sports (dancers, gymnasts, bodybuilders, distance runners, and wrestlers) are most susceptible to poor nutrient intake

– Women are most susceptible than men

l Iron + B vitamins were most deficient

– Low caloric intake is primary reason for poor nutrition

How important is nutrition to sport performance?

l It may make the difference between winning and losing in a major competition

– Malnutrition represents unbalanced nutrition as either:

l Undernutrition (lack of adequate nutrients)

l Overnutrition (excessive amounts of single or multiple nutrients)

Nutrition for training

l Since energy expenditures increase with additional physical training, it is recommended that:

– An additional 500-1,000 calories per day be included in diet, depending on sport activity

l Adjustments to the energy systems will need to occur also. This is called the “chronic-training” effect

Dietary Supplements and Health

l What is a dietary supplement?

– A food product, added to the total diet, that contains at least one of the following ingredients:

l Vitamin

l Mineral

l Herb or botanical

l Amino acid

l Metabolite

l Constituent

l Extract

l Combination of the above ingredients

Will dietary supplements improve health?

l Not in nutritionally-prudent individuals

l May be helpful in certain circumstances

– Women in child-bearing age may reduce poor pregnancy outcomes by taking folate

l May be hurtful in other circumstances

– Ephedrine-containing supplements for weight loss have result in deaths

l First supplement to be banned by Federal government

Dietary Supplements and Sports Performance

l Ergogenic aids

– Substances or devices used to increase potential for work output or performance

– Types

l Mechanical

l Psychological

l Physiological

l Pharmacological

l Nutritional

Ergogenic Aids in Sports

l May be effective in some cases, but not in others; examples of some cases of use:

– Carbohydrates – compounds enhance utilization during activity

– Fats – alternative fuel to CHO’s

– Protein – stimulate muscle growth and development

– Vitamins – increased strength & increased vision (B₁₅)

– Minerals – anabolic in nature (chromium, vanadium, boron)

– Water – oxygenated water to increase O₂ delivery

Nutritional Quackery

l The business of promoting a worthless nutritional product

– High level of false claims exist

l May originate from

– Star athletes

– Coaches will little or no knowledge of nutrition

– Sport magazines and books

– Direct marketing (most significant contributing factor in sports)

Where do we find the answers to nutritional questions?

l Epidemiological research

– Study of large populations to find relationships between 2 or more variables either at one point in time or over a number of years

l Experimental research

– Study of treatment groups (including a control or placebo group) to establish cause and effect relationships between variables