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Chapter 11

Lecture Slides

Introduction

• Weight loss programs

• Clinical programs• Medically supervised

• Nonclinical programs• Commercial programs

• Counselors; usually not health professionals

• Example: Weight Watchers

• Do-it-yourself programs• Behavior modification

• Diet

• Exercise

Basics of Weight ControlHow may Calories are in a pound of body fat?

• 1 pound of fat = 454 grams

• 1 gram of fat = ~ 9 Calories

• 1 pound of pure fat = ~ 4,086 Calories

• Body fat contains some protein, minerals and water

• 1 pound of body fat = ~ 3,500 Calories

Is the caloric concept of weight control valid?

• First Law of Thermodynamics

– Energy is neither created nor destroyed

Caloric Concept of Weight Control

• Caloric costs for changes in body mass

– Fat = 9 Calories per gram

– Protein = 4 Calories per gram

– Carbohydrate = 4 Calories per gram

– Water = 0 Calories per gram

• Caloric cost of weight loss may vary

• Loss of body fat, however, costs about

3,500 Calories /pound

Caloric Concept of Weight Control

• Calories from food may vary slightly

– Fat may be stored more efficiently

– Protein may increase the TEF

– Alcohol may be stored as abdominal fat

• However, caloric balance is the key to weight control

How many Calories do I need per day to maintain my body weight?

• Estimated Energy Requirement (EER) Technique

– Review Chapter 3

– EER is the dietary energy intake predicted to maintain energy balance in a healthy individual

– EER same as Total Daily Energy Expenditure (TDEE)

• EER components

– Resting energy expenditure (REE)

– Thermic effect of food (TEF)

– Thermic effect of exercise (TEE)

Total Daily Energy Expenditure

Estimated Energy Requirement (EER)

• A key factor is the Physical Activity Level (PAL), which is the TDEE divided by the BEE. The PAL is used to determine the Physical Activity (PA) coefficient

Physical Activity Level (PAL)

Institute of Medicine bases the PAL on the amount of daily physical activity that is the equivalent of walking at a pace of 3-4 MPH, or 15-20 minutes per mile

– Low Active (PAL 1.5): Walk 2.2 miles

– Active (PAL 1.75): Walk 7 miles

– Very Active (PAL 2.2): Walk 17 miles

You need not actually walk this amount, but do other physical activities that are the equivalent of walking a mile, such as using an elliptical trainer for 12-15 minutes

Sedentary and very active females

22 years old; 132 lbs (60 kg); 55 inches (1.4 m)

Calculating your EER

• Access the MyTracker Program

– www.MyPyramid.gov

• Use the “Standard Option”

• Once enrolled, you may access the site directly

– www.MyPyramidTracker.gov

Calculating your daily energy expenditure

• Other methods

– Calorie Counting Technique

• If body weight is stable

• Calculate daily caloric intake (MyPyramid)

– Simplified technique

• Approximate caloric intake per pound body weight

How much weight can I losesafely per week?

• Without medical supervision

– Recommended maximal amount

• Adults: 2 pounds/week

• Growing children: 1 pound/week

– Realizable goals

• Adults: 1 pound/week

• Growing children: ½ pound/week

– Weight loss should be body fat

How can I determine the amount of body weight I need to lose?

• Set realistic goals

– Appearance

– Health

– Sport performance

• Seek professional help if necessary

Determining Weight Loss Goals

• Body Mass Index protocol

– Target body weight is in kilograms (kg)

• Target body weight = Target BMI x height in meters²

– Height in meters = Height in inches x 0.0254

– 67” x .0.0254 = 1.70 meters


• Example of Body Mass Index protocol

– 5’7” (1.70 m) male weighs 170 pounds (77.2 kg)

– BMI is currently 26.7 (77.2 ÷ 1.70²); slightly overweight

– Goal is a healthier BMI of 23

– Target body weight = 23 x 1.70² = 66.5 kg (146 pounds)

• Weight loss = 24 pounds

• Weight loss = 14% (24 ÷ 170)


• Body-fat, lean body mass (LBM) percentage protocol

• Target body weight = Lean body mass in pounds

1 ― desired body-fat %


• Example of body fat , lean body mass protocol

– Athlete weighs 150 pounds, is 20% body fat, 80% LBM

• Lean body mass = 120 pounds (150 x .80)

– Goal is 15% body fat

– 120 = 120 = 141 pounds

1.00 – 0.15 0.85

Athlete needs to lose 9 pounds (150 – 141 = 9 pounds)

Behavior ModificationWhat is behavior modification?

Model system for health improvement

• Knowledge

– Have proper knowledge about benefits of diet and exercise

• Values

– Develop set of personal values or attitudes

• Behavior

– Modify behavior to reflect your values

Behavior Modification

• Learn new ways to deal with old problems

• For weight control, reduce or eliminate physical or social stimuli that contribute to

– Excessive caloric intake

– Physical inactivity

• Learn to eat a leaner, healthier diet

• Learn to exercise more

How do I apply behavior-modification techniques in my weight-control program?

• YOU are the most important component of your weight-control program

• YOU must– Face the fact that being overweight impairs your health

– Know that losing weight will improve your health

– Establish weight loss as a high priority

– Be able to tolerate some discomfort as you make changes

Behavior Modification

• One of the first steps is to identify your dietary and exercise behaviors - Keep a 24-hour record

Diet and Exercise Behaviors

• Establish long-range and short-range goals

– Long-range• Lose 10-15% of body

weight over 4-6 months

– Short-range• Lose 1-2 pounds per week

• Small behavior changes

– “ Nothing builds success like success”

– Small Steps

Small Stepswww.smallstep.gov

• Website provides numerous small steps relative to diet, cooking, drinking, and exercise that help promote weight loss. There is a set for children and another for teens and adults.

Behavior Modification: Suggestions

• Self-discipline, self-control, and advanced planning

• Foods to eat

• Food purchasing

• Food storage

• Food preparation and serving

• Location

• Restaurant eating

• Methods of eating

• Activity

• Mental attitude

Self-discipline, self-control, and advanced planning

• Establish realistic weight-loss goals

• Establish weight loss as a high priority

• Think about this priority before eating

• Take small helpings deliberately

• Plan for a modest daily caloric deficit

• Check your body weight on a regular basis

Foods to eat

• Use low-Calorie healthful foods for snacks

• Plan low-Calorie, high-nutrient meals

• Plan your food intake for the entire day

• Eat only foods that require no or minimal processing

• Allow yourself small amounts of foods you like, but stay within daily caloric limits

• Know the Food Exchange system, particularly portion size and high-fat foods and Calories per exchange

Food purchasing

• Do not shop when hungry

• Prepare a shopping list and do not deviate from it

• Buy only nutrient-dense foods

• Read and compare food labels

• Buy natural foods as much as possible

Food storage

• Keep high-Calorie foods out of sight

• Have low-Calorie snacks like carrots and radishes readily available

Food preparation and serving

• Buy mainly foods that require preparation of some type

• Do not add fats or sugar in preparation, if possible

• Prepare only small amounts. Be able to visualize one serving size for any given food

• Do not use serving bowls on the table

• Put the food on the plate, preferably a small one

Location

• Eat in only one place, such as the kitchen or dining area

• Avoid food areas such as the kitchen or snack table at a party

• Avoid restaurants where you are most likely to buy high-Calorie items

Restaurant eating

• When eating out, select the low-Calorie items

• Request your meals be prepared without fat

• Have condiments, like butter, mayonnaise, and salad dressing served on the side; use sparingly

• Order water, not a high-Calorie beverage

• Be wary of portion sizes as most restaurant servings contain 2-3 normal servings. Ask for a take-home container before you eat and put half of your meal in the box.

Methods of eating

• Eat slowly. Chew your food thoroughly or drink water between bites

• Eat with someone; conversation slows eating

• Cut food into small pieces

• Do not do anything else while eating

• Relax and enjoy the meal

• Eat only at specified times

• Eat only until pleasantly satisfied, not stuffed

• Spread your total Calories over the day; snack often

Activity

• Decrease the amount of time spent being sedentary

• Increase the amount of daily NEAT

• Walk more

• Use the stairs, not the elevator or escalator

• Do exercise snacks. Brisk 10-minute walk

• Get involved in physical activities with others

• Avoid sedentary night routines

• Start a regular exercise program, both aerobic and resistance exercises

• Schedule exercise as an appointment in your daily planner

Mental attitude

• Recognize that you are not perfect and that lapses will occur

• Deal positively with your lapse; put it behind you and get back on your program

• Put reminders on the refrigerator door at home or on your telephone at work

• Reward yourself for sticking to your plans

Weight maintenance

• Maintaining your new healthy body weight is the key

• Lifelong commitment to healthy diet and exercise behaviors is needed

• Prevent a lapse from becoming a relapse

– Injury can curtail exercise

– Have alternative exercises you can do

• National Weight Control Registry

– Maintained weight loss for at least 2 years

Dietary Modifications

• To lose weight, the key component is Calories

– One needs to consume fewer Calories than one expends

• Proponents of macronutrient diets

– High carbohydrate

– High fat

– High protein

How can I determine the number of Calories needed in a diet to lose weight?

• First, calculate how many Calories (C) you need daily to maintain your current body weight

• Second, estimate how much weight you want to lose each week.

• Example:

– 35-year old sedentary woman needs 1,820 C to maintain current body weight at 140 pounds

– To lose 1 pound/week would require a 500 C daily deficit

– 1 pound of fat = 3,500 Calories; 3,500 ÷ 7 = 500 C

– 1,830 ― 500 = 1,330 C day diet

How can I predict my body-weight loss through dieting alone?

Why does a person usually lose the most weight during the first week on a reducing diet?

• The goal is to lose body fat, not muscle

• Weight loss via dieting may come from decreased body stores of carbohydrate and protein and resultant body water losses, which require no Calories

– Carbohydrate stores may also bind water

– Carbohydrate losses: 300 grams

– Associated water losses: 900 grams

– Total losses: 1,200 grams (1.2 kg), or 2.6 pounds

– Water is also lost with muscle protein losses

• Loss of 1 pound occurs with < 3,500 Calorie deficit

Why does it become more difficult to lose weight after several weeks or months on a diet program?

1. Body water losses decrease

– Body weight losses are now primarily from body fat, which requires an energy deficit of 3,500 Calories

2. At your lower body weight, you need fewer daily Calories to maintain this weight

– Example: Male who needs 18 Calories/lb to maintain weight

• 200 lbs x 18 = 3,600 Calories to maintain weight

• 180 lbs x 18 = 3,240 Calories to maintain weight

3. To maintain a set rate of weight loss, you would need

to cut more Calories from the daily diet

What are the major characteristics of a sound diet for weight control?

• Hundreds of diet plans have been proposed

– Fast and easy diet plans

• No such diet

• Most diet plans focus on macronutrients

– Acceptable Macronutrient Distribution Range (AMDR)

• Carbohydrate: 45-65% of energy intake

• Fat: 20-35% of energy intake

• Protein: 10-35% of energy intake

Popular Diets (Diet Books)

Diet Plan Average Daily Calories

%

Carbohydrates

%

Fat

%

Protein

Weight watchers

1,450 56 24 20

Atkins 1,520 11 60 29

South Beach 1,340 38 39 23

Volumetrics 1,500 55 23 22

Jenny Craig 1,520 62 18 20

Zone 1,660 40 30 30

Ornish 1,520 77 6 17

Adapted from Consumers Union. Rating the Diets.

Consumer Reports 70 (6):21, 2005.

Low-fat, High-carbohydrate Weight-loss Diets

• Examples of diet plans

– Ornish – Eat More and Weigh Less

– Rolls – Volumetrics

– Glycemic Index diet

• Key point of such diets

– Fruits, vegetables, whole grains

– High fiber content

Low-carbohydrate, High-fat Weight Loss Diets

• Example of diet plans

– Atkins

– South Beach Diet

• Key points of such diets

– Start with 20 grams of carbohydrate daily

– Foods rich in fat and protein

– May be more satisfying

– Gradually increase carbohydrate, but still low

– Low in Calories

High-protein Weight-loss Diets

• Example of diet plans

– Zone (40:30:30)

– Possibly Atkins and South Beach

• Key points of such diets

– Protein is 30% or more of energy intake

– Effects of protein

• Increase thermogenesis

• Maintenance of lean body mass

• Decrease levels of ghrelin with eating; decrease appetite

Balanced Weight-loss Diets

• Examples of diet plans

– Various health profession organizations

• Key points of such diet plans

– Reduced in Calories yet supply all essential nutrients

– Contain a wide variety of foods that appeal to your taste and help prevent hunger between meals; moderate in fat

– Suited to your current lifestyle and personal preferences

– Provide a slow rate of weight loss; 1-2 pounds/week

– A lifelong diet

Weight-loss Diet Plans

• Current research

– The Calorie content of the diet is the key factor

– Diets varying in carbohydrate, fat, or protein are equally effective if caloric content is similar

Popular Diets

Diet Plan Average Daily Calories

%

Carbohydrates

%

Fat

%

Protein

Weight watchers

1,450 56 24 20

Atkins 1,520 11 60 29

South Beach 1,340 38 39 23

Volumetrics 1,500 55 23 22

Jenny Craig 1,520 62 18 20

Zone 1,660 40 30 30

Ornish 1,520 77 6 17

Adapted from Consumers Union. Rating the Diets.

Consumer Reports 70 (6):21, 2005.

Is it a good idea to count Calories when attempting to lose body weight?

• Counting Calories may be helpful during early stages of a diet

• Learning the Food Exchange System and using Food Labels helps you learn the caloric contents and serving sizes of various foods, which can help in the selection of low-Calorie, nutrient dense foods

• Keep track of foods rich in fat and sugar

What is the Food Exchange System?

How can I determine the number of Calories I eat daily?

• Carry a notebook with you and a reminder, such as a rubber band on your finger

• Record your daily food intake, and physical activity, in detail, as soon as possible

• Record food intake over a 3-7 day period of time which represents your normal dietary habits

• Use the Food Exchange System or Nutrition Facts on food labels to record serving size and Calories

• Use measuring devices, such as a measured cup

• Learn to estimate portion sizes

Figure 11.5

Determining Caloric Intake

• Eating out

– Fast-food restaurants

• Nutrition fact sheets

• See Appendix F

– Other restaurants

• Use PDA or cell phone

• Email [email protected]

• Receive response with Calorie, fat, and carbohydrate content

Determining Caloric Intake

• Enter food record into MyPyramid dietary analysis program

• You may keep a record of your caloric (energy) intake over the course of a year

What are some general guidelines I can use in the selection and preparation of foods to promote weight

loss or maintain a healthy body weight?

• Consumer Reports study of 32,000 dieters who lost weight and kept it off

– The National Weight Control Registry

• No specific plan but used sensible strategies

– Cut portion sizes

– Eat fewer Calories from fat and sugar

– Eat healthier carbohydrates, fats, and proteins

Guidelines for Weight Control and Healthy Eating

• Twenty (20) guidelines based on reputable sources

– National Weight Control Registry

– Consumers Union

– Dietary Approaches to Stop Hypertension (DASH) diet

– Optimal MacroNutrient Intake for Heart Health diet (OmniHeart)


1. Decrease caloric intake -- eat more nutrient-dense foods and fewer energy-dense foods

2. Eat foods that make you feel full

3. Restrict portion sizes

4. Eat less fat

5. Eat fewer and smaller amounts of refined sugar

6. Reduce the intake of both fat and sugar

7. Eat more low-fat dairy products


8. Eat more low-fat meat and meat substitutes

9. Eat more whole, unprocessed carbohydrates

10. Eat more fruits

11. Eat more veggies

12. Consume fewer high-Calorie fat exchanges

13. Reduce liquid Calories

14. Limit intake of alcohol

15. Limit salt intake


16. Eat slowly

17. Nibble, don’t gorge

18. Eat breakfast

19. Learn to cook

20. Learn low-Calorie foods


1. Eat more nutrient-dense foods and fewer energy-dense foods


2. Eat foods that make you feel full

Volumetrics: High-volume, low-Calorie foods

Soups

Salads

Vegetables

Whole grains


3. Restrict portion sizes

Evolution of Coca-Cola

8-ounce bottle

12-ounce bottle

20-ounce bottle

64-ounce fountain serving

Evolution of fast-food hamburgers

Single 4-ounce patty

Double burger

Triple burger


4. Eat less fat

Proposed rationale:

• Rich in Calories

• Appetizing and does not rapidly suppress the appetite

• Has a lower TEF or higher metabolic efficiency

• May be stored preferentially in the abdominal area

Use fat substitutes


5. Eat fewer and smaller amounts of refined sugar

• Reduce intake of sugar-sweetened beverages

• Use sugar substitutes


6. Reduce the intake of both fat and sugar

• May constitute 50% of daily energy intake


7. Eat more low-fat dairy products

• Rich in protein, vitamins and minerals, especially calcium


8. Eat more low-fat meat and meat substitutes

• Very lean meat exchange

• Fish, chicken breast, beef eye of round, flank steak

• 35 Calories, 1 gram of fat

• High in protein

• Low in fat

• Low in Calories

• Rich in minerals (iron and zinc)


9. Eat more whole, unprocessed carbohydrates

• High volume food

• Rich in fiber

• Select 100% whole wheat or whole grain


10. Eat more fruits

• Select fresh fruits

• Select canned or frozen fruits in own juices

• Avoid fruits in heavy sugar syrups

• Limit intake of dried fruits (high in Calories)

• Limit intake of fruit juices (high in Calories)


11. Eat more vegetables

• High volume foods

• Low in Calories

• Rich in vitamins, minerals, fiber, phytonutrients

• Many vegetables are listed as Free Food Exchanges

• Fewer than 20 Calories per serving


12. Consume fewer high-Calorie fat exchanges

• Reduce intake• Butter

• Margarine

• Cooking oils

• Salad dressing

• Mayonnaise

• Most are pure fat

• Use fat-free or low-fat versions


13. Reduce liquid Calories

• Beverages other than milk and fruit juice should have no Calories

• Sweetened sodas and drinks may be associated with weight gain and obesity

• Some specialty coffees contain as many Calories as McDonald’s Big Mac• Starbucks Choclaty Chip Frappuccino Blended Crème > 500 Calories


14. Limit your intake of alcohol

– A gram contains 7 Calories, comparable to fat

– Calories in alcohol do not replace Calories in a meal, so total caloric intake is increased

– Selecting low-alcohol beer and wine may help save Calories

• 64 Calories versus 150 Calories

• Decreased carbohydrate and alcohol


15. Limit salt intake

• Salt may increase appetite

• Salt may increase thirst for sugar-sweetened beverages

• Use herbs, spices and other nonsalt seasonings


16. Eat slowly

• Eating slowly may help curb your appetite

• Eat a low-Calorie soup or salad as an appetizer

• May help curb the appetite for the main course


17. Nibble, don’t gorge

• Eat 5-6 smaller snacks and meals during the day

• May help curb the appetite

• Use low-Calorie, nutrient-dense foods

• 100-Calorie snacks• An apple

• A hard-boiled egg

• A dozen almonds

• 3 Hershey’s kisses

• 3 cups of air-popped, fat free popcorn


18. Eat breakfast

• A hearty breakfast may help curb appetite through the morning hours

• A high-protein breakfast may be helpful

• Egg substitutes

• Whole wheat bagels with salmon

• Whole grain cereals with skim milk and fruit


19. Learn to cook

• Select healthy foods

• Cook and serve small portions

• Ease of cooking

• Microwaves

• Electric grills


20. Learn low-Calorie foods

• Learn to substitute low-Calorie foods for those high in Calories

• Know the Food Exchange System

• Practice what you learn

• Gradual transition in small steps

• Whole milk → low-fat milk → skim milk

How can I plan a nutritionally balanced, low-Calorie diet?

Are very-low-Calorie diets (VLCD) effective and desirable as a means to lose body weight?

• VLCD are modified fasts (< 800 Calories/day)

• May be used under medical supervision

• Not recommended for typical individual who wants to lose 10-20 pounds

Is it harmful to overeat occasionally?

• Occasional overeating is not harmful to dieting, as long as it does not become a habit

• Try to avoid high-fat meals if prone to cardiovascular disease

• Rapid weight gain from overeating may occur, but is not body fat

– Water retention with carbohydrate stores

– Water retention with excess sodium

• Getting back on your weight loss plan will return body weight to normal

Exercise and Weight Control

Exercise ProgramsWhat role does exercise play in weight reduction

and weight maintenance?

• Physical inactivity is one of the major contributing factors to the development and maintenance of overweight and obesity

• Research studies with twins

– The physically active twin had significantly less fat than physically inactive twin


Two ways to increase total daily energy expenditure

• Decrease the time you are physically inactive

– Reduce TV viewing

– Increase NEAT

ExerciseHow to get more into your day!

• Walk to work

• Walk during lunch hour

• Take family walk after dinner

• Do yard work

• Wash car by hand vigorously

• Pace the sidelines at kid’s athletic games

• Park as far as possible from store entrance

• Take the stairs instead of the escalator

• Walk anytime you can


Two ways to increase total daily energy expenditure

• Decrease the time you are physically inactive

– Reduce TV viewing

– Increase NEAT

• Start a planned exercise program

– Resistance exercise

– Aerobic exercise


• Resistance exercise benefits

– May help preserve lean body mass as muscle

– May help prevent decrease in REE associated with dieting

– May help motivate individuals to a more physically active lifestyle

• Energy expenditure with resistance exercise

– Relatively low compared to aerobic exercise

– May be increased in circuit-type training

• Resistance training discussed in Chapter 12


• Aerobic exercise benefits

– Most effective means to increase energy expenditure


• Energy expenditure ↑ with ↑ in exercise intensity

• Walking faster expends more energy


• The Long-haul concept

– Average-size male expends about 100 Calories jogging a mile

– 3,500 Calories equals 1 pound of body fat

– Need to jog 35 miles to lose 1 pound

– Jog 2-3 miles daily will lose 2 pounds in a month, which is the long-haul concept

Exercise and Weight ControlLong-haul Concept

• Caloric expenditure in walking and running 1 mile– Slow, leisurely walking = 0.45 calorie/pound body weight – Running = 0.73 calorie/pound body weight

• To burn 1 pound of body fat (3500 calories) in 154-lb male– Walking would burn about 69 calories per mile; need to walk about 50

miles– Running would burn about 114 calories per mile; need to run about 31

miles

EXERCISE AND WEIGHT CONTROLLong-haul Concept

• Walk 4 miles daily 5 days a week

Burns 1400 Calories per week

Lose about 5 pounds in 3 months

• Jog/run 4 miles daily 5 days a week

Burns 2300 Calories per week

Lose about 8 pounds in 3 months



– May increase RMR slightly after exercise

– May help prevent the decrease in REE seen with dieting

• However, may decrease the REE in athletes who are already lean

– Manifold health benefits

• Reduce abdominal fat

• Reduce symptoms of the metabolic syndrome



– Prevention of initial weight gain

• Prevention of childhood obesity

– Prevention of weight regain

• Maintenance of weight loss

• Essential for lifelong maintenance of healthy body weight

– If you like to eat but not gain weight, exercise is the intelligent alternative

Does exercise affect the appetite?

• Short-term effects

– Intense exercise (> 65% VO²max) may ↓ the appetite

• Increased core temperature

• Increased epinephrine

– Exercise before evening meal

• Long-term effects

– A compensatory increase in energy intake

– Individual variability

– Women seem to compensate more and maintain weight

Does exercise affect the set point?

• The settling point

– Some suggest that individual may reach a level of fat and energy balance at lower levels of body fatness, indicative of a settling of the set point to a lower level

– May be a limit. Ghrelin increases with increased exercise-induced weight loss. Ghrelin stimulates the appetite

What types of exercise programs are most effective for losing fat?

• Aerobic exercise

– Mode

– Intensity

– Duration

– Frequency

– Enjoyment

– Practicality

– Versatility

Aerobic Exercise

• Mode of exercise

– Large muscle groups

– Rhythmic exercises

Aerobic Exercise

• Intensity of exercise

– Beginners should start with low-intensity exercise

– Use the Principle of Progression

– To maximize energy expenditure, exercise at an intensity appropriate for the amount of time you have to exercise

– Check Appendix B to find high-energy activities for your body weight

Aerobic Exercise

• Duration of exercise

– The duration concept is probably the most important factor in total exercise energy expenditure

– Study conducted for 30 months• Subjects expended either 2,500 or 1,000 Calories/week

• Subjects in 2,500 group lost 25 more pounds

– Time versus distance• Energy expenditure much greater running for 1 hour versus playing

tennis for 1 hour

– Exercise snacks: 4 x 10 minutes same as 40 minutes

– Intensity and duration are interrelated

– Increase duration as your endurance capacity improves

Aerobic Exercise

• Frequency of exercise

– Weekly energy expenditure

– 3-4 days may be satisfactory if intensity and duration are adequate

– 6-7 days often recommended for weight control

• Goal for weight control (Duration and Frequency)

– About 2,000-2,500 Calories per week

Aerobic Exercise

• Enjoyment of exercise

– Find an activity you enjoy

• Aerobic dancing

• Singles tennis

• Pickleball

– Treat work as play

• Mowing the lawn with push mower

• Vacuuming the house vigorously

Aerobic Exercise

• Practicality of exercise

– Limitations

• Lack of partners

• Lack of facilities

• Weather

• Costs

– Bias towards walking and running

• Brisk walking ideal for most weight control programs

• Walk or run anywhere

• Low cost and little equipment necessary

– Indoor exercise equipment may be practical

Aerobic Exercise

• Versatility of exercise

– Do a variety of activities weekly

• Run

• Cycle

• Swim

• Elliptical trainer

• Racquetball

– Less likely to become bored

– May help prevent overuse injuries

– May provide alternative exercise if you are injured

If I am inactive now, should I see a physician before I initiate an exercise program?

• Health professional recommendations

– If you are young (20s-30s) and have no risk factors, it is probably safe to initiate an exercise program

– The older you are, the better the idea to have a medical exam; it is prudent for all those over age 40

– Be aware of any personal medical problems that might be aggravated by exercise

– Have a medical examination if you have any coronary heart disease risk factors

What other precautions would be advisable before I start an exercise program?

• If overweight and unconditioned, start easy.

– Walking is the recommended exercise

– Walk before you jog

– Progress slowly

• Safety factors

– Cycling safety

– Pedestrian safety

• Meal time

– Avoid strenuous exercise for 2-3 hours after heavy meals

• Be aware of symptoms of heat stress

What is the general design of exercise programs for weight reduction?

Typical Exercise Sessions

• Warm-up

– Warm up the specific muscles to be used

– Do the same activity as you will do during the stimulus period, but at a slower pace

– Gently stretch muscles to be used in the stimulus period

• Warm-down or cool-down

– Decrease the intensity of the same exercise used during the stimulus period for about 5-10 minutes

– Helps maintain blood circulation

– Avoid exercise-associated collapse

– More active stretching of the warm muscles

What is the stimulus period of exercise?

Stimulus Period for Aerobic Exercise

• ACSM/AHA Guidelines presented in Chapter 1

– Intensity• Moderate

• Vigorous

– Duration• Minimum of 20-30 minutes

• More for weight loss

– Frequency• 5 days a week moderate

• 3 days a week vigorous

• Possibly more for weight loss

What is an appropriate level of exercise intensity?

• Variety of techniques to express exercise intensity

– VO2max

– Calories/minute

• Practical methods

– Heart rate

– RPE

– The Talk Test

Measures of Exercise Intensity

• Heart rate

– Manual palpation

– Heart rate monitor


• Heart rate method

• Various formulae to predict maximal heart rate (HRmax)

– Original formula

• 220 - age

– Updated formula

• 207 – 0.7 age

– Formula for physically trained men

• 205 – 0.5 age

– Formula for obese individuals

• 200 – 0.5 age


• Predicted HRmax for 40- and 70-year old male

40 70

– Original formula

• 220 – age 180 150

– Updated formula

• 207 – 0.7 age 179 158

– Formula for physically trained men

• 205 – 0.5 age 185 170

– Formula for obese individuals

• 200 – 0.5 age 180 165

Measures of Exercise Intensity• Maximal heart rate method

– Example: 40-year old male with HRmax of 180

– 60-80% of HRmax = target heart rate range of 108-144


• Heart rate: Target heart rate range (Karvonen method)

– Expressed as a percentage of heart rate range• Also known as heart rate reserve

• Heart rate range = HRmax – RHR

– Karvonen’s formula• Target HR = X% (HRmax – RHR) + RHR

– Example• Individual with HRmax of 180 and RHR of 70

• Goal is to exercise at 60% of HR range

• Target HR = 0.60 (180 – 70) + 70

• Target HR = 0.60 (110) + 70

• Target HR = 66 + 70

• Target HR = 136


• Maximal heart rate reserve method

– Based on maximal (HRmax) and resting heart rate (RHR)

• Target HR = X% (HRmax ― RHR) + RHR

– Example: 40-year old male with HRmax of 180, RHR of 70

– Target range of 60-80% of HRmax reserve • 0.6 (180 ― 70) + 70 = 66 + 70 or 136

• 0.9 (180 ― 70) + 70 = 99 + 70 or 169

– Target heart rate range = 136 - 169


• Ratings of Perceived Exertion

– Scale based on your perception as to how hard you are exercising

– Scales based on values of 1-10 and 6-20

• The 6-20 scale is related to heart rate

• Add a 0 and the value should be similar to your heart rate

Exercise Intensity

• Moderate

– 40-60 % of aerobic capacity

– 5-6 on 10-point RPE scale

• Vigorous

– > 60% of aerobic capacity

– 7-8 on 10-point RPE scale


• The Talk Test: Based on respiratory effort

• You can first hear your breathing

– Entering into the lower range of HR zone

• Breathing harder but able to carry on a conversation in complete sentences

– Moderate-intensity exercise

• Difficult to carry on conversation in complete sentences

– Vigorous-intensity exercise

How can I determine the exercise intensity needed to achieve my target HR range?

• Exercise test to measure heart rate and RPE response

– Select your exercise• Walk, Run, Cycle, Swim, Row, Indoor equipment, etc.

– Exercise about 4-6 minutes to reach steady-state HR

– Recover after each exercise bout to reduce heart rate

– Do about 4-5 bouts of exercise

– Do 1st bout very easy

– Increase exercise intensity on 2nd and subsequent bouts

– Monitor intensity, HR, and RPE responses for each bout

Determining Personalized Exercise Intensity

• Example: Female with HRmax of 200 and RHR of 70

• Target HR range of 50-85% HR reserve = 135-180

• Walk/jog 0.5 mile at increasing speeds

• Test 2 is just below 50% level

• Test 3 is middle range

• Test 4 is at the upper limit Test Time RPE HR Min/Mile

1 8:00 11 108 16:00

2 7:10 13 132 14:20

3 6:30 15 156 13:00

4 6:00 18 180 12:00

How can I design my own exercise program?

• Clues from research with successful exercisers

1. Do not exceed your abilities during early stages

Start slowly

Walking slowly ↓ ankle forces in obese persons

Designing your own exercise program


2. Set both short-term and long-term goals

Short: Walk a mile in 15 minutes

Long: Walk the Rock `n Roll Half Marathon



3. Keep a record of your exercise

Buy a pedometer or accelerometer



4. Find the time to exercise

Block out time in your daily planner

Exercise before work, at lunch, or after work

Exercise while watching TV



5. Find a convenient place to exercise

Local fitness facility close to home or work

Buy exercise equipment for home use

Walk, jog, or run anywhere



6. Stay motivated to exercise

Enjoy exercising

Exercise with others

Become skilled at your exercise

Know that exercise will enhance your health

Walking as an Ideal Exercise

• Efficacy

– Aerobic, or brisk, walking

– Goal: 10,000 steps/day

• Practicality

– Convenience

– Cost

• Safety

– Reduced chance of injury

• Graduate to jogging, running

– Interval training

Energy Expenditure during Walking and Running

Example: 154 pound (70 kg) male

Walking:

70kg x 1.0 Calories = 70 Calories per mile

154 x 0.45 Calories = ~ 70 Calories per mile

Running:

70kg x 1.6 Calories = 112 Calories per mile

154 x 0.73 Calories = ~ 112 Calories per mile

Walking Running

Calories/kg/mile 1.0 1.6

Calories/lb/mile 0.45 0.73

Cool Websites

How much exercise is needed to lose weight?

• The magnitude of exercise needed for weight loss may be greater than what is necessary to elicit significant improvements in health

• ACSM/AHA exercise guidelines for health

– 30 minutes of moderate-intensity exercise

– About 200-250 Calories of energy expenditure per session

– 5 days per week totals about 1,000 to 1,250 Calories

• ACSM/AHA notes that more exercise is better

Exercise to Lose Weight

• ACSM position stand on weight control

– 4.5 hours of moderate intensity per week

– Approximately 2,000 Calories energy expenditure weekly


– Expend about 1,500-2,000 Calories weekly via exercise

• Institute of Medicine /National Academy of Sciences

– 60 minutes daily; walking or jogging at 4-5 MPH

– Approximates 2,000 Calories energy expended weekly

From what parts of the body does the weight loss occur during an exercise weight reduction program?

• Body weight losses via dieting

– Some muscle protein

– Some glycogen

– Some water losses

– Some fat losses

• Body weight loss via exercise

– Mainly body fat

– May increase some muscle

Should I do low-intensity exercises to burn more fat?

• Low-intensity exercise

– Caloric energy expenditure is low

– % of energy derived from fat Is high

• Higher levels of exercise intensity

– Caloric energy expenditure increases

– % of energy derived from fat decreases

– However, total caloric expenditure increases and Calories derived from fat may increase or stay the same

• Remember, exercise training makes one a better fat burner at all levels of exercise intensity

Is spot reducing effective?

• Studies with local muscular exercise

– Sit-ups and abdominal fat

– Resistance training and upper arm fat

– No effect of exercise on subcutaneous fat

• Exercise-associated fat loss occurs where body fat is most conspicuous

– Primarily the abdominal area, including visceral fat

• Gluteal fat, as in gynoid-type fat distribution, more resistant to change

Is it possible to exercise and stillnot lose body weight?

• Body changes with exercise

What about the five or six pounds a person may lose during an hour of exercise?

• Rapid weight losses

– Sweat

– 1 pint = 1 pound

• May lose 10-12 pounds or more in a summer workout

• Regain body weight with fluid intake

Comprehensive Weight-Control Programs

• Comprehensive program

– Behavior modification

– Diet

– Exercise

• Most important feature

– Maintenance of stable healthy body weight

• Lifelong commitment

What is more effective for weight control—dieting or exercise?

• Dieting alone may be an effective means to lose excess body fat

– Increasing protein content may help maintain muscle

– Some indicate dieting alone to maintain weight is designed to fail in the long run

• Exercise alone may also be an effective means to lose body fat

– Dietary energy intake needs to remain constant

Dieting and Exercise for Weight Control

• Combination of dieting and exercise is the most effective approach to weight control

– A proper diet can control energy intake

– A proper aerobic and resistance exercise program provides multiple benefits• Expends caloric energy

• Prevent decrease in lean body mass

• Maintain resting energy expenditure (REE)

• Exercise may improve dietary compliance



• Average member has lost about 70 pounds and has kept it off for 6 years


• National Weight Control Registry: Key behaviors

– Eat a low-Calorie diet; low in fat and high in carbohydrate

– Eat breakfast; reduce hunger later in the day

– Watch only a limited amount of television

– Do about 60 minutes or more of physical activity daily; walking is the favorite exercise. Also engage in aerobic classes and resistance training. Expend about 2,000 Calories weekly through physical activity

– Weigh themselves frequently; daily or several times a week; helps prevent a lapse from becoming a relapse

If I want to lose weight through a national or local weight-loss program, what should I look for?

• Proper qualifications of health professionals

• Medical screening

• Reasonable weight goal and rate of weight loss

• Individualized program

• Behavior modification component

• Planned diet and exercise program

• Weight maintenance phase

• Written contract with risks/benefits explained

Selecting a health club or fitness facility

• Qualification of the staff

– No national standards for personal trainers

– Check certification• American College of Sports Medicine (www.acsm.org)

• American Council on Exercise (www.acefitness.org)

• National Strength and Conditioning Association (www.nsca-lift.org)

• Variety and availability of exercise equipment

What type of weight-reduction program is advisable for young athletes?

• American Academy of Pediatrics recommendations

– Gradual weight loss over realistic time frame• Not to exceed 1-2 pounds per week

– Eat enough to cover the energy costs of daily living, growth, and energy for sport participation• Carbohydrate (55-65%); fat (20-30%); protein (15-20%)

– Lose excess body fat, not muscle or water by dehydration

– Lose weight by both diet and extra exercise

– Maintain body weight once obtained; no weight cycling

– Discuss weight loss with health-care professional and family

What is the importance of prevention in a weight-control program?

• Treatment of obesity is difficult

• Prevention appears to be the key approach

• Small changes to prevent creeping obesity

– Walk 2,000 more steps daily

– Remove 100 Calories from daily diet

– This combination will prevent 1.5 pound weight gain monthly

Figure 11.16

Prevention of weight gain

• Importance for children– Neural circuits may be formed; difficult to eradicate

• Need multipronged efforts– Government set standards for ads to children

– Food manufacturers produce healthier products

– Communities plan recreational facilities

– Schools provide daily physical education

– Parents provide healthy foods and limit sedentary behavior

Weight Control

• The Bottom Line

Eat less, move more

Diet and Exercise for Weight Control

• Eat less– Fat– Sugars and refined carbohydrates

• Consuming less fat and sugar isoften all that is needed to reducedaily caloric intake by 200-300 calories

• Eat more– Whole grains– Fruits and vegetables– Lean fish, poultry, meat– Low fat dairy products

• Move more– Daily activities– Planned exercise

Exercise, Diet & Body Weight

• Useful Web siteswww.MyPyramid.govEstimated energy expenditureClick MyTracker

Enter physical activityClick Energy Balance

www.MyPyramid.gov/kidsPrograms for children

www.Americaonthemove.orgSuggestions for exercise and diet forweight control

www.smallstep.govHow to incorporate exercise and healthy nutrition into daily life; ideas for adults, teens, children

chapter 11 lecture slides - cerritos collegeweb.cerritos.edu/nbueno/sitepages/nutrition for...

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