Chapter 5Metabolism and Ideal Weight

Why has there been an increase in eating disorders?

What can we do to stop the trend in eating disorders?

What are some healthy reasons to control your weight?

How can you control your weight in a healthy way?

Define Metabolism

Metabolism is the chemical reactions that occur in the body to break down food and build new materials.

Why do we need food?

The body breaks down food so it can be used for energy and other purposes?

What is a calorie?Energy content of food

How many calories should I eat?

The amount of calories you should consume is determined by 2 factors:

1. Basal metabolism rate (BMR)2. Level of activity

Basal Metabolic Rate (BMR)The amount of energy it takes to keep your

body functioning normally when you are at rest.

Differs from individual to individualHigh Fitness level = faster BMRMen vs. womenAge

Energy Balance EquationYou can maintain your current body weight if

you balance the number of calories you eat with the number of calories you burn.

Calculating your Caloric Needs1. Calculating BMR Calories

Females: body weight (pounds) x 10Males: Body weight (pounds) x 11

2. Calculating Activity LevelsActivity Level %BMR CaloriesMultiply ByInactive 30 .30Average Activity 50 .50Strenuous Activity 75 .75

3. Calculating Calories Needed to Digest Food

(BMR Calories + Activity Calories) (0.1) = Digestion Calories

4. Total Calories needed = Step 1 + 2 + 3

Body CompositionYour body is made of several kinds of tissue,

fat & lean mass (muscle)

Fat: Essential Fat & Storage

Essential FatMen 3%Women 10% - 12%

How is body fat measured?Under water weighingSkin-fold calipersBioelectrical impedance

Can you be overweight and still be healthy?Do height/weight charts tell you how healthy

you are?

3500 Calories = 1 lb of fatIncreasing your intake by 500 calories a day

one 20 ounce sodaIn 7 days you will gain 1 lb of fat

Decreasing your intake by 500 caloriesOne 20 ounce sodaIn 7 days you will lose 1 lb of fatWhat if you also exercise to burn an extra 500

calories? Jog, bike, or swim for about 30 minutes

Lose weight sensiblyEstablish weight goal based on excess body fat

not body weightCombine diet and exercise: most effective

At lease 20 minutes to burn fat, not carbohydrates

Plan to lose no more than 4 lbs a monthDrink plenty of water (at least 64 ounces)

Body is about 70% waterDevelop eating habits for a lifetimeNever skip meals (slows metabolism)

Eat smaller meals more often

Fad DietsA weight-loss plan that promises unrealistic

results.Quick fix, but unrealisticTake advantage of peoples emotionsCan be dangerous to your healthWeight lost generally returns when you go

back to your old eating habits.Metabolism slows down