TOPIC 3.1: ENERGY BALANCE

Question 1

WHAT IS A CALORIE? HOW CAN THEY BE DETERMINED? WHAT IS A KILOCALORIE?

Answer 1

• a unit of meaurment for energy contained in a food
• can be determined by determining the amount of heat transferred into water when food is burned (in calorimeter)
• a kilocalorie is the amount of energy needed to raise the temp of water from 15 to 16ºC

Question 2

WHEN DO THE BODIES ENERGY STORES CHANGE?

Answer 2

change when energy in is different than energy out

Question 3

WHAT IS THE RELATION IN ENERGY DEFECIT, ENERGY EXCESS, AND ENERGY BALANCE AND CONNECTION TO WEIGHT GAIN

Answer 3

energy defecit: energy intake < energy need = weight loss
energy excess: energy intake > energy need = weight gain
energy balance” energy intake = energy need = weight maintenence

Question 4

WHAT ARE THE DIFFERENT TYPES OF WAYS THE BODY USES ENERGY? WHAT PERCENTAGE OF ENERGY DO THEY USE?

Answer 4

1. basal metabolic rate: takes up 60-75% body expendtiture. it is used to maintian things like HR, breathing, nerve impulses, etc (not digestion)
2. activity energy expenditure is voluntary activities and takes up 16-35%
3. thermic effect on food (TEF) is a percentage of energy in a meal thats used in stepped at metabolism hour after a meal (peristalsis, segmentation, etc), takes up 5-10%

Question 5

WHAT FACTORS INCREASE BMR

Answer 5

• gender (male)
• higher lean body mass
• younger age
• elevated thyroid hormone levels
• stress, fever, illness
• pregnancy, lactation
• certain drugs, coffee, tobacco, stimulants

Question 6

WHAT FACTORS DECREASE BMR

Answer 6

• female gender beause less lean tissue
• less lean body mass
• older age
• depressed thryoid hormone levels
• lower height
• starvaiton, fasting, certain diets