Physical activity, sedentary behaviour & body mass Flashcards
Food intake in excess of energy expenditure is called ?
Positive Energy balance
Food intake less than energy expenditure is called?
Negative energy balance
How is energy provided to the body via nutrients?
Catabolism of nutrients
What maintains homeostasis when it comes to nutrition?
Dietary intake must be approximately equal to energy expenditure
How many calories are in 1 g of lipids?
9 kcal
Again of protein contains how kCal?
4 kCal
How many kCal are in1g of carbohydrates?
4 kCal
What is Basal metabolic rate (BMR)?
Is the energy expenditure by the body when at rest, but not asleep, under controlled conditions of thermal neutrality, measured about 12 hours after the last meal, and depends on weight, age and gender
What does the Total energy expenditure depend on ?
Depends on BMR, the energy required for physical activity, and the energy cost for synthesising reserves in the fed state
What if the formula for Metabolic Rate Energy Output?
Metabolic rate energy output= external work + energy storage + heat
What is Catabolism?
oxidation of carbohydrates , proteins and fats to produce carbon dioxide and Water and ENERGY
What is Anabolism?
Energy can be stored in the form of energy rich phosphate compounds and in the form of proteins, fats and complex carbohydrates
Energy requirement varies with what?
Varies with age
Varies with sex
Varies with activity level
What is the Total Energy Expenditure (TEE)?
Number of calories needed per day
What is the Total Energy Expenditure (TEE)?
(1) Resting Energy Expenditure or basal metabolic rate
(2) Thermic effect of food (Rough estimation: TEF = Total calories consumed/day x 0.1)
(3) Activity - Activities of daily living (ADL) - physical activity. (PA)
What is BMR?
Basal Resting Metabolism
Accounts for 60-75% of daily expenditure
What is the most important determinant of BMR?
Body size
BMR is higher in leaner individuals
True or false?
True
What is the REE?
Resting Energy Expenditure,
What is Thermic effect of feeding (TEF) ?
TEF is the energy cost of digestion, absorption, processing and storage of nutrients
Comprises about 10% of TEE in sedentary individuals
There are no significant differences in between ages or gender
Lower TEF is often seen in obese individuals
What is diet induced thermogenesis?
increase in metabolic rate after a meal
The most useful way of expressing the energy cost of physical activities is as a multiple of BMR.
True or false?
True
This is known as the physical activity ratio (PAR) or metabolic equivalent of the task (MET).
How much hBMR di sedentary activities use?
About 1.1 to 1.2 x BMR
What is PAL physical activity level ?
is the sum of the PAR of different activities, multiplied by the time taken for that activity, divided by 24 hours.
At any weight, a person whose body weight and physical activity remain stable must consume the same number of calories as are expended.
True or false
True
As weight (body mass) increases, basal metabolism and the cost of carrying the extra weight in activities both rise gradually, roughly in proportion to the weight gain. So continued weight gain will occur only if the calories consumed continue to rise.
True or false?
True
For continued weight loss, to treat obesity, energy intake must fall further to remain at a level below the reduced energy expenditure
True or false?
True
What is the equation for EER Estimated Energy Requirement ?
EER = 354 - (6.91 x age [y]) + PA x { (9.36 x weight [kg]) + (726 x height [m]) } women
EER = 354 - (6.91 x age [y]) + PA x { (9.36 x weight [kg]) + (726 x height [m]) } me
What are the factors that affect metabolic rate?
Muscular exertion during or just before measurement Recent ingestion of food High or low environmental temperature Height, weight, and surface area Sex Age Growth Reproduction Lactation Emotional state Body temperature Circulating levels of thyroid hormones Circulating epinephrine and norepinephrine levels
What is the BMI based on gender?
Men: Desirable = Less than 94, High = 94-102, Very high = More than 102
Women: Desirable = Less than 80, High = 80-88, Very high = More than 88
What are the advantages of BMI ?
Easy to measure and to monitor
Simple and easy to understand
Good indication of body fatness in the majority of people
Widely used in scientific journal articles, by health reporting bodies and medical professionals
What are the disadvantages of BMI?
Not as reliable in children
Not suitable for those with high lean body mass (i.e. high proportion of muscle)
Does not represent percentage body fat
Does not give any indication of central adiposity (increased health risk)
Reducing energy intake has the central role in weight loss and prevention of regain will help
prevent discouragement.
true or false?
True
