Lecture 5 - Weight Management Flashcards
Metabolic Syndrome and Symptoms
1 in 5 Canadians have metabolic syndrome
Diagnosis is have 3 or more of the following conditions:
- High blood pressure
- High blood glucose levels
- High Trigycerides
- Low HDL Cholesterol
- Large Waist Circumference
Metabolically Healthy Obesity
Commonly defined as having 0,1,2 of symptoms
Therefore having MHO is guys having fewer metabolic abnormalities then unhealthy obesity
Studies have shown that even metabolically healthy obese people are still more at risk of mortality
What is energy?
The capacity to do work
Work = force x distance
Energy usually observable by the performance for work done and/or in the form of heat (abstract)
Units of energy
1 Joule = 1 newton metre
Calories = nutritional energy
1000 small c calories = 1 kilocalorie (C or kcal)
1 kcal = roughly 4.1 kilojoules (kJ)
First Law of Thermodynamics
Law of conserving energy (ATP=chemical energy)
Energy can’t be created or destroyed to can only be transferred in between forms
Change in body’s energy stores = energy intake -energy expenditure
Energy balance equation
Change in body’s energy stores = energy intake -energy expenditure
Where:
energy intake = energy content of food ingested
Energy expenditure=energy used for various purposes
Change in body’s energy stores = energy intake - (RMR+TEF+EAT+NEAT). Dynamic equation
Total daily Energy Expenditure (TDEE)
BMR/RMR (resting metabolic rate) =energy required for basal physiological functions at rest
EAT (Exercise activity thermogenesis)= energy required for thermal exercise
NEAT (Non-exercise activity thermogenesis)= energy required for daily movement
TEF (Thermic effect of food)= energy required to metabolize
RMR/BMR
Energy required for body to perform basic functions and energy required by the body at resting condition
50-70% of TDEE
RMR is proportional to lean body mass
Energy for substrate utilized
At rest we rely on fats RER=0.7
During exercise we rely on carbs RER=1.0+
RER (respitatory exchange ratio) gives info on proportion of fat vs carbs oxidized for energy
Respitatory Exchange info
For energy yeild, 1 L O2 consumed = 5kcal
we often used VO2 as a proxy for energy expeniditure
EAT
Refers to the energy expenditure for formal exercise
Varies on intensity and duration, hard to say on TDEE but roughly 5% on average
Measuring energy expenditure during physical activity
METs (metabolic equivalents) is the measurement used to determine energy expenditure.
1-3 is light intensity
sleeping
watching tv
3-6 is moderalty intensity
walking
light cycling
7-10 is vigorous intensity
1 MET = 1kcal/kg/hour
NEAT
all physical activity that is not formal exercise
everyday actives
Can have large cumulative effect on overall energy expenditure
around 15%
TEF
After eat our metabolic rate increases
TEF referes to the energy expenditure of processing and food storing
TEF=10% of TDEE
proteins =20-30% thermal effect of food
Carbs= 5-10%
Fats=0-3%
Dynamic energy balance equation
Change in body’s energy stores = energy intake - (RMR+TEF+EAT+NEAT)
body weight is lost, RMR may decrease
since it is proportional to lean mass
When less food is eaten, thermic effect of food decreases. More energy spent when eating
NEAT may decrease with diet and increased exercise. More tired and less daily movement
These factors can all impact energy expenditure
