ENERGYCh.12

WHAT IS ENERGY

Ability to do work.Types of energy: Chemical Mechanical Heat

Cannot create or destroy it; can only change form

http://safari.pisd.edu/?a=47764&ch=2&d=00267AA

ENERGY IN

CALORIES3 WAYS TO GET ENERGY CARBOHYDRATES (what your body prefers)

FATS PROTEINS

HOW DO I KNOW HOW MUCH ENERGY IS IN MY FOOD?

A FOODS CALORIE VALUE IS A MEASURE

OF THE HEAT IT GIVES OFF WHEN IT IS BURNED IN A

BOMB CALORIMETER!

THE ENERGY IT TAKES TO RAISE WATER THE ENERGY IT TAKES TO RAISE WATER 1 DEGREE CELISIUS = 1 CALORIE1 DEGREE CELISIUS = 1 CALORIE

http://safari.pisd.edu/?a=47771&ch=3&d=00308AA

Calorie Density

CONCENTRATION OF ENERGY IN FOOD

DIVIDE GRAMS INTO CALORIES

THE MORE WATER CONTENT OF FOOD….THE LESS CALORIE DENSE

(WATER DOESN’T BURN)

ENERGY OUT

Three reasons you need energy. Basal Metabolism Physical Activity Thermic Effect of Food

ALL THESE added TOGETHER EQUALS

= THE TOTAL AMOUNT OF ENERGY (CALORIES)

YOU NEED DAILY

BASAL METABOLISM

60% of your calories are used for this functionBasal Metabolism is the amount of energy needed to support the operations of all internal body systems

What are some of the ways your body uses basal metabolism?

Breathing Blood Circulation Maintaining Nerve Activity Secreting Hormones Maintaining Body Temperature Make new cells

BMR

Basal Metabolic Rate is the rate at which the body uses energy for basal metabolism.Women require approximately .4 calorie per pound, per hourMen require .5 calorie per pound, per hourWhat is your basal energy need?

WHAT EFFECTS BMR?

Body structure

Body composition – percentage of different tissues in the body;

Fat Muscle Bone

Gender

Age

Body Temperature

Diet

Disease Thyroxine

Physical Activity

Need energy to move your musclesNeed energy for extra breathes and circulation while working or exercisingEnergy output varies depending on body size. The larger the body, the more energy is needed.Actual amount of movement of

muscles will affect total energy output

PHYSICAL ACTIVITY

30% of your calories are used for this functionSleep

You burn 60 calories per hourSedentary Activities

Reading, Eating, Watching TV, Playing cards, Using a computer

You burn 80-100 calories per hour (average 90)

Light Activities Cooking, Doing Dishes, Ironing, Walking slowly

You burn 110-160 calories per hour (average 135)

Physical Activity cont’d

Moderate Activities Walking, Making a bed, light gardening,

Standing activities requiring arm movement You burn 170-240 calories per hour (average 205)

Vigorous Activities Walking fast, Golfing, Yard Work

You burn 250-350 calories per hour (average 300)

Strenuous Activities Running, Dancing, Bicycling, Playing football,

Playing Tennis, Cheerleading, Swimming, Skiing You burn 350 or more calories per hour

Determining Your Calorie Needs for Physical Activity

Indirect Calorimetry- measures a persons oxygen intake and carbon dioxide output.

THERMIC EFFECT OF FOOD

10% of your calories are used for this functionEnergy required to complete the processes of digestion, absorption,and metabolism.Energy required to extract the energy from food.Depends on the types and amount eaten

ENERGY IMBALANCE

Occurs when a person consumes too few or too many calories for his or her energy needs.

ENERGY DEFIENCY

Occurs when energy intake is less than energy output.Food sources may be scarce.Illness may depress appetite“ Ketone Bodies”- when the body changes fatty acids into compounds to meet energy needs.“Ketosis” –abnormal buildup of ketone bodies in the bloodstream.

Energy Deficiency

No carbohydrates to burn as energy, body burns fat (weight loss)Body changes fat into “Ketone Bodies” to use as fuel for the nervous system“Ketosis” is abnormal buildup of ketone bodies in the bloodstreamLow carbohydrate diets and starvation will set up a “state of ketosis”.Atkins Diet an exampleDifficult on kidneys and heart

ENERGY EXCESS

Occurs when energy intake is greater than energy output.Body can use stored energy when there is not enough food intake to meet immediate energy needs.If there is excess energy on a regular basis- weight gain occurs3500 calories = 1 pound of stored fat

LOCATION OF BODY FAT

Fat stored in the abdomen seems to pose a greater risk than fat stored in the buttocks, hips, and thighs.Fat around the waist increase the liver’s production of low density lipoproteins, which is a risk factor for heart disease.

KEY TO WEIGHT MANAGEMENT IS BALANCING ENERGY IN WITH ENERGY YOU EXCERT!