Lecture 12 Flashcards
Energy =
Energy IN - Energy OUT
Where is Energy IN from?
From food and beverages
What is Energy OUT?
Heat loss (radiant and evaporation) and work
What energy does Energy In count for?
Metabolisable energy only
What are the 4 ways to spend energy?
- Resting Energy Expenditure
- Thermic Effect of Food
- Physical Activity
- Growth
Define BMR
- Basal Metabolic Rate
- Energy expended at rest to fulfil life-sustaining functions
Describe the conditions of BMR
- Very strict condition
- Relaxed physical and mental state
- Thermoneutral environment
- Fasted for 12 hours
- Well rested
From BMR calculations which parts of the body use the most energy?
- Muscle
- Brain
- Liver
What is the Resting Energy Expenditure
(same as BMR)
-Energy expended at rest to fulfil life-sustaining functions
What’s the difference between BMR and Resting Energy Expenditure
BMR has much stricter conditions making it more difficult to measure, REE doesn’t have strict conditions.
What can Resting Energy Expenditure be affected by?
- Body weight/height
- Fat free mass (brain/heart/kidney/liver)
- Fat mass
- Age, gender
- Hormones
- SNS
What is Diet-Induced Energy Expenditure?
The energy needed for digestion and processing of food
What % of energy does Diet-Induced Energy Expenditure make up?
Approx 10%
What causes Diet-Induced Energy Expenditure to vary?
Varies with diet consumption
-Fat needs less energy, then carbohydrates, then protein needs the most energy
What determines Diet-Induced Energy Expenditure?
- Amount of food/food composition
- Hormones
- SNS
What are the two measures for physical activity?
- Activity-Induced Energy Expenditure (AIEE)
2. PAL (physical activity level
What are the determinants of physical activity?
- Intensity
- Duration
- Body weight
- Genetics
What is the equation for positive energy balance?
Energy IN > Energy OUT = Growth
What is the equation for negative energy balance?
Energy IN < Energy OUT = Weight Loss
What is the equation for energy balance?
Energy IN = Energy OUT -> adults
- fluctuates throughout the day
- highly variable
- balance achieved over longer period
What is the effect of a decrease in Energy IN for children and adults?
It slows growth in children
-they will still grow, but not to potential
Adults will be hungry
What are the global trends for energy intake?
Starvation and obesity are both increasing
