Lecture 9: Diet Planning: Food First Supplements Second

Post on 12-Jan-2017

755 views 0 download

Transcript of Lecture 9: Diet Planning: Food First Supplements Second

NDD 30503LECTURE 9

Diet Planning: Food First Supplements Second

DR. SHARIFAH WAJIHAH WAFA BTE SST WAFA & HH04

MONDAY (7 NOVEMBER 2016), 2:00-4:00PM

Introduction to Diet Planning• A diet is a pattern of eating

• Athletes should match dietary intake to training

• Both energy (kcal) and nutrient intakes are important

Introduction to Diet Planning

• It is relatively simple to obtain needed nutrients with the increased caloric intake associated with regular, moderate-intensity exercise. In contrast, a person with a sedentary lifestyle needs fewer calories and should choose more nutrient-dense foods.

Energy: The Basis of the Diet Planning Framework

• Humans are designed to be biologically active o Active individuals need more kcalo Higher caloric diets make it easier to obtain needed

nutrientso Caloric need for athletes can range considerably

• Energy needs will vary with training cycleo Usually lowest in the “off-season”o High volume training periods can substantially

increase needo Daily intake of no less than 30 kcal/kg is not typically

recommended

Estimating Daily Energy Needs of Athletes

Training Schedule and Estimated Energy Expenditure of a Female Collegiate Rower

Dietary Prescription

• Helps athletes consume the proper amount of macronutrients within energy needso Consider carbohydrates and proteins firsto Fats and alcoholo Add in discretionary calories

o excess calories to enjoy once your required nutrient needs are met. They can be used toward higher-fat forms of foods like milk, cheese and meat, and high-fat and sugary toppings such as butter, sauce, sugar and syrup.

Modifications to Reduce Body Fat

• “Discretionary calories” reduced or eliminated• Mild to moderate reduction in dietary fat• Increased energy expenditure• Goal is to not reduce daily intake below 30

kcal/kg• Larger deficits make it difficult to train • Individualized diet plan needed

Underweight Athletes

• Goal is usually a 500 kcal per day increaseo Increasing portion sizes and eating often

• Difficult for underweight athletes to increase weight

• Individualized diet plan needed

Nutrient Density• Relatively high concentrations of nutrients

compared to kcalo Most fruits and vegetableso Whole grains, beans, legumeso Lower fat meat, fish, poultry, and dairy productso Not necessarily low in kcal (e.g., nuts)

• Low nutrient dense foodso Sugaro Alcoholo When sugar and fat are added, nutrient density typically

declines

Nutrient Density of Skim and Whole Milk

Nutrient Density of Sugar and Alcohol

Translating Nutrient Recommendations into Food Choices

• Guidelines for meal planningo Food Intake Patterns (ChooseMyPlate)o Especially useful for those with little knowledge of

nutritiono Public domain information

• Individualizing a diet plano The key to diet planningo May involve a new dietary patterno May involve modification of current diet

Guidelines for Food and Fluid Intake Prior to Exercise

Food and Fluid Intake Prior to Exercise

• Goalso Provide energy for exercise, particularly CHOo Delay fatigue during prolonged exerciseo Prevent hypohydration and excessive dehydration oMinimize gastrointestinal distresso Satisfy hunger

Guidelines for Food and Fluid Intake Prior to Exercise

• All guidelines are subject to trial and error• Timing

o Work backwards from time of exercise onset (if known)o Adjust volume of food and fluid based on time

• CHO o 1.0 g/kg body weight 1 hr prior, 2.0 g/kg 2 hrs prior, etc.o Depends on gut tolerance

• Protein and fato Some protein is usually includedo Fats provide satiety but must allow for slow absorption

• Adjust pre-training guidelines for pre-competition intake• The wrong pre-competition meal is more detrimental than the

right pre-competition meal is beneficial!

Guidelines for Food and Fluid Intake Prior to Exercise

Guidelines for Food and Fluid Intake During Exercise

Food and Fluid Intake During Exercise —Goals

• Provide energy, particularly CHO• Delay fatigue • Prevent hypohydration and excessive

dehydration • Prevent excessive changes in electrolyte

balance• Replace sodium, if losses are large or rapid• Minimize gastrointestinal distress

Food and Fluid Intake During Exercise —CHO

• Limited CHO stores• As endurance exercise continues, higher percentage derived

from blood glucose• Liver glycogen tries to compensate but gluconeogenesis

capacity is limited• CHO intake allows blood glucose concentration to remain

within the normal range• Studies show CHO intake of ~ 30 to 60 g/hr can delay fatigue• Intake beneficial for endurance, ultraendurance, and “stop-

and-go” athletes

Food and Fluid Intake During Exercise —Fluids and Electrolytes

• Customized fluid and electrolyte intake plan• Avoid over- or underconsumption of fluid• Excessive sodium losses should be replaced

during exercise• Endurance athletes often include CHO in the fluid

o ~ 4 to 8% CHO

Guidelines for Food and Fluid Intake During Exercise

Guidelines for Food and Fluid Intake After Exercise

Food and Fluid Intake After Exercise — Goals

• Provide carbohydrate to resynthesize muscle glycogen

• Provide proteins to build and repair muscle • Rehydrate and re-establish dehydration • Replace lost electrolytes• Avoid gastrointestinal upset

Food and Fluid Intake After Exercise — Timing

• Begin recovery strategies as soon after exercise as practical• Cell sensitivity and permeability is high• Carbohydrate

o Muscle glycogen synthesized at highest rate immediately after exercise

o Two-hour delay results in substantial reduction of muscle glycogen resynthesis

o ~ 1.5 g/kg body weight in first hour post-exerciseo Medium to high glycemic index foods are beneficial o ~ 0.75 to 1.5 g/kg each hour over the next three hours

Food and Fluid Intake After Exercise — Protein

• Intake immediately after exercise is beneficial• At least 6 g of indispensable amino acids needed• ~ 0.1 g/kg indispensable amino acids• Be practical (e.g., chocolate milk, turkey sandwich)

Food and Fluid Intake After Exercise — Fluid and Electrolytes

• Intake immediately after exercise is important• ~ 1.5 L (1,500 ml) fluid per kg of body weight lost• Consume enough fluid to be euhydrated before next

exercise session• Replenish lost electrolytes (e.g., sodium)

Guidelines for Food and Fluid Intake After Exercise

Caffeine

• Legally and socially acceptable stimulatory drug

• Primary ingredient is methylxanthine• Considered safe at low doses, but does have

side effects• May be a banned substance at certain urinary

concentrations

Caffeine Content of Selected Foods, Beverages, and Medications

Safety of Caffeine• Generally considered safe but addictive• Side effects

o Increased blood pressure at rest and during exerciseo Increased heart rateo Gastrointestinal distresso Insomnia

• Moderate doses of 200 – 300 mg/day are recommendedo Doses greater than 500 mg may result in irritability, anxiety,

headaches, etc.o Moderate doses in athletes do not negatively affect hydration

statuso Use in hypohydrated athletes is a concern

Effectiveness of Caffeine• As a performance enhancer• Fatty acid mobilization increased but does not

spare muscle glycogen• Effective as a central nervous system stimulant• For weight loss• By itself, does not result in fat or weight loss• Enhances the effect of ephedrine

Dietary Supplements and Ergogenic Aids

• May contain banned substances• Except for creatine, most have not been well studied in

athletes• Few dose-response studies• Label recommendations may not be same as used in

research• Few have been shown to enhance performance• Some have been shown to be detrimental• There is no substitute for disciplined training and proper

diet

Supplements — The Professional’s Role

• Provide as much unbiased, scientific information as possible

• People who sell supplements are not a source of unbiased information

• Express concerns about potential side effects• “Guide but don’t decide” (athlete’s decision)

Understanding a Dietary Supplement Label

• Serving size• Amount• Percent Daily Value• Ingredient list• Additional information• Principal Display Panel• Health and structure/function claims

Supplement Facts Label

Evaluating the need for a multivitamin and mineral supplement involves estimating current intake, awareness of safe levels, and weighing the risks and benefits.

Vitamin and Mineral Supplements

• Most widely used supplement by athletes• Benefit depends on dietary intake• If diet is adequate in nutrients,

supplementation will not improve performance

• May be beneficial to offset a dietary deficiency

Protein Supplements

• Can consume enough protein from food• Supplements may be convenient• Not more or less effective for increasing

muscle mass than food proteins

Botanical and Herbal Supplements

• Often used as alternative medications• Most are more drug-like than food-like• Garlic, soy, and phytochemical supplements

are more closely related to food

A Comprehensive Nutrition Plan to Support Training and Performance

• Periodization • Nutrition Periodization— development of a

nutrition plan that parallels the demands of each training cycle

• Requires understanding of sport and position played

• Each has unique demands• Body composition goals vary

Questions????