ENERGY BALANCE AND BODY

COMPOSITION

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DO NOW

Describe the difference between BMR and BMI

Refer to your notes on metabolism for help.

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ENERGY BALANCE

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WHAT IS ENERGY BALANCE AND WHY IS IT IMPORTANT?

An energy imbalance results in weight gain or loss. Positive energy balance: Energy intake is more than

energy expended Weight gain from:

increased muscle mass increased adipose tissue or both

Periods of growth: pregnancy, childhood, and adolescence

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WHAT IS ENERGY BALANCE AND WHY IS IT IMPORTANT?

Negative energy balance: Energy expended is more than energy intake Food intake is reduced, more energy is expended through

exercise, or both Results in weight loss

Fat loss Muscle loss Loss of glycogen or water

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WHAT IS ENERGY BALANCE AND WHY IS IT IMPORTANT?

Body processes and physical activity result in energy out. Energy needed throughout the day will vary for each

individual based on: Basal metabolism Thermic effect of food (TEF) Thermic effect of exercise (TEE) Adaptive thermogenesis

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ENERGY BALANCE

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ENERGY IS USED FOR PHYSICAL ACTIVITY OR EXERCISE Thermic effect of exercise (TEE): Increase in

muscle contraction that occurs during physical activity Amount of kilocalories you need for TEE depends on the

activity performed, duration of activity, and how much you weigh

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ENERGY USED FOR DIGESTION AND ABSORPTION IS CALLED THE THERMIC EFFECT OF FOOD (TEF) Thermic effect of food (TEF): Energy used to

process the macronutrients and extract kilocalories from food 10 percent of kilocalories in food consumed is used for

TEF. Meals high in protein have greater TEF than those high in

carbohydrate, which have greater TEF than those high in fat.

TEF is influenced by Type of nutrients consumed, composition of a meal, alcohol

intake, age, and athletic training status

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ENERGY IS USED FOR ADAPTIVE THERMOGENESIS

Body's regulation of heat production influenced by environmental changes such as stress, temperature, or diet All result in a change in metabolism.

Some researchers think it explains why two people can have similar diets and exercise patterns but differing body compositions.

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(less than 30 min of activity)

WHAT IS BODY COMPOSITION AND HOW IS IT ASSESSED?

Body composition: The ratio of fat tissue to lean body mass (muscle, bone, and organs) Usually expressed as percent body fat Important for measuring health risks associated with

too much body fat

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MOST BODY FAT IS STORED IN ADIPOSE TISSUE

Two types of fat make up total body fat. Essential fat

Essential for the body to function Women have more essential fat (12%) than men (3%)

Stored fat Found in adipose tissue Subcutaneous fat is located under the skin. Visceral fat is stored around the organs in the abdominal

area. Insulates the body from cold temperatures Protects and cushions internal organs

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VISCERAL AND SUBCUTANEOUS FAT STORAGE IN THE BODY

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WHAT'S YOUR BMI?

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HOW DO WE ESTIMATE A HEALTHY BODY WEIGHT? (CONT'D) Interpreting the BMI values:

Obese individuals have a 50 to 100 percent higher risk of dying prematurely than those at a healthy weight.

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BMI Classification

18.5–24.9 Healthy Weight

25–29.9 Overweight

≥ 30 Obese

HOW DO WE ESTIMATE A HEALTHY BODY WEIGHT? (CONT'D) BMI is not a direct measure of percent of body fat.

BMI may not be accurate for everyone. Athletes and some individuals: BMI > 25 but have high muscle mass and low body fat

Older adults with chronic weight loss: May have healthy BMI but significant loss of muscle mass and depletion of nutrient stores

Individuals less than 5 feet in height may have a high BMI, but not be unhealthy.

Combine indirect measurements to get a better estimate of body composition

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USING BMI AND WAIST CIRCUMFERENCE TO DETERMINE HEALTH RISK

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WHAT ARE THE HEALTH RISKS ASSOCIATED WITH BODY WEIGHT AND BODY COMPOSITION? Being underweight increases health risks.

Symptomatic of malnutrition, substance abuse, or disease

Higher risk of anemia, osteoporosis and bone fractures, heart irregularities, and amenorrhea

Correlated with depression and anxiety, inability to fight infection, trouble regulating body temperature, decreased muscle strength, and risk of premature death

May be unintentional and due to malabsorption associated with diseases such as cancer, inflammatory bowel disease, or celiac disease Also may be due to certain medications, smoking, and

substance abuse

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HEALTH RISKS ASSOCIATED WITH BODY WEIGHT AND BODY COMPOSITION Being overweight increases health risks.

Overweight and obesity are associated with increased risk of heart disease, hypertension, stroke, gallstones, hyperlipidemia, sleep apnea, and reproductive problems.

Increases risk of certain cancers, including colon, breast, endometrial, and gallbladder cancer

More than 80 percent of people with type 2 diabetes are overweight.

Metabolic syndrome is associated with central obesity.

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DOL

1. A BMI of what number or higher indicates that an adult is obese?

a. 20.7b. 25c. 28d. 30

2. A sedentary person does less than how many minutes of moderate to heavy physical activity a day?

a. two hoursb. one hourc. 30 minutesd. 15 minutes

3. Being physically active can help you:a. increase your chances of living longerb. feel better about yourselfc. decrease your chances of becoming depressedd. all of the above