Energy requirements & measurement of energy expenditure

Question 1

macronutrient balance

Answer 1

• CHO, prot. & alcohol not easily converted to body fat
• increase intake -> increase oxid’n rates
• increase fat intake does noyt increase oxid’n rate of fat -> fat storage

Question 2

energy intake needs to cover the energy costs of:

Answer 2

• daily living
• sport
• building & repairing mus. tissue
• menstruation & reproduction
• growth in younger athletes

Question 3

BMR - RMR diff between sedentary people & athletes (depending on sport)

Answer 3

60-80% of total EE in sed
35-55% of total EE in athletes

Question 4

Thermic effect of food

Answer 4

6-10% of total EE but will depend on energy content, type of food, macronutrient comp. etc

Question 5

Thermic effect of activity - sedentary vs athletes

Answer 5

sed 10-15% of EE
ath. up to 50%

Question 6

factors that influence RMR

Answer 6

• age, sex & body size -> 80% of RMR - RMR decreases with age, lower in females, increase FFM -> increase RMR
• genetics
• energy balance
• exercise - RT increase FFM

Question 7

Measuring total EE

Answer 7

• indirect calorimetry (measures vco2 & vo2)
• doubly labelled water (measures VO2)

Question 8

Estimating total EE

Answer 8

• Schofield, Harris-Benedict
• RMR estimated x activity factor = total EE
• PAL range: 1.4(sed) - 2.5(v active)