Midterm Flashcards
lectures up to Feb 8 (74 cards)
1
Q
Physical Activity
A
- any bodily movement produced by the skeletal muscles that results in energy expenditure above resting (basal) levels
- this encompasses exercise, sports, and physical activities done as part of daily living, occupation, leisure and active transport
2
Q
Exercise
A
- physical activity that is planned, structured, and repetitive
- has a final or intermediate objective the improvement or maintenance of physical fitness
3
Q
Nonexercise activity thermogenesis (NEAT)
A
- the portion of daily energy expenditure which results from spontaneous physical activity that is not exercise
4
Q
Aspects of physical fitness
A
- health-related fitness: capacity of an individual to carry out the physical activities of daily living without undue fatigue
- skill-related fitness: related primarily to successful sports and motor skill performance
5
Q
What are the major systems involved in exercise? (5)
A
- nervous system
- skeletal muscle
- cardiovascular system
- respiratory system
- neuroendocrine system/metabolism
6
Q
a “muscle-centric” view of exercise
A
- muscles are the direct source of movement
- “service” organs facilitate muscle work by permitting continued exercise and maintaining homeostasis and facilitating allostasis
7
Q
three factors of health and longevity
A
- environment
- behaviours
- genetics
8
Q
what percentage of deaths are due to poor diet and sedentary behavior?
A
?????ASK SOMEONE
9
Q
lifestyle diseases
A
- sitting disease: hastens the deterioration of the human body
- sedentary death syndrome: causes of death attributed to lack or regular PA
- Hypokinetic disease: illness related to lack of PA
10
Q
24 hour movement guideline for adult
A
- 7-9 hrs of sleep
- 150 MVPA mins/week
- sedentary behavior below 8hr
11
Q
Physical activity levels defined
A
- light PA (uses <150 calories/day): walking to and from work, taking stairs, household chores
- Moderate PA (uses 150 calories/day or 1000 calories/week): brisk walking or cycling and raking leaves
- vigorous PA (requires >6 METs): sports and exercise
12
Q
Energy expenditure
A
- the total amount of energy expended during exercise
- this includes the resting energy expenditure
- may be articulated in METs, kilocalories, or kilojoules
13
Q
MET = metabolic equivalent
A
- and index of energy expenditure
- MET is the ratio of the rate of energy expended at rest
- one MET is the rate of energy expenditure while sitting at rest and is equal to oxygen uptake of 3.5mL/kg/min
14
Q
MET-minutes
A
- an index for the total amount of physical activity (per day/week)
- calculated as the product of the number of METS of an activity and the time spent doing it (METs x mins)
15
Q
V02 Max
A
- the maximal rate of oxygen uptake
- oxygen uptake (mL) per kg body mass per min
16
Q
Examples of the benefits of PA
A
- important for muscle, bone, and joint health
- improves mood, cognitive function, creativity
- enhances the brain function
17
Q
Why are people not meeting PA guidelines when we know the benefits?
A
- it is hard to change
- our behaviors are based on our core values and personal nature
- we resist changes that are not immediately rewarded
18
Q
what triggers people to want to change their habits
A
- receiving gratification for their action
- having their feelings addressed
19
Q
anchor points
A
- social norms that individuals use as a reference when considering a new behaviour
- in our current world, physical and social obstacles of PA promote unhealthy practices and norms that are our anchor points
20
Q
what is the role of the basal ganglia
A
- area of the brain where habits are formed
- striatum (largest nucleus of the basal ganglia) plays a key role in habit formation and contains dopamine to reinforce
21
Q
what is the role of the prefrontal cortex
A
- helps you change habits because it is able to focus on long-term values
- PFC reminds us who we are
- puts the brake on impulsive behaviour
- predicts outcomes based on previous experience
- serotonin (confidence chemical) is abundant here
22
Q
Learning theories
A
- most behaviors are learned and maintained under complex schedules of reinforcement and anticipated outcomes
23
Q
problem solving model
A
- many behaviors result from making decisions as the individual seeks to solve a problem behavior
24
Q
social cognitive theory
A
- behavior change is influenced by the environment, personal factors, and characteristics of behavior itself
25
relapse prevention model
- people are taught to anticipate high risk situations and develop action plans to prevent lapses and relapses
26
Structure of a research paper
- abstract
- introduction
- methods
- results
- discussion
27
panel consensus judgement
- expert judgement is based on the panel's synthesis of evidence and/or deprived from the consensus of panel members based on clinical experience or knowledge that does not meet the above listed criteria
28
can exercise negate sitting?
- there is a study that suggests that 1 hour of PA can eliminate the detrimental effects of 8 hours of physical inactivity
29
how does PA benefit health
- decreases risk of CVD
- increases life span
- prevention and management of type 2 diabetes
30
why does body composition matter
- overweight and underweight individuals are at higher risk of certain illnesses
31
what factors can classify someone as obese
- not only body weight - has more to do with overall composition
- individuals who are normal weight can still be classified as obese if they have a high fat content
32
BMI classifications
- >30kg/m^2 is classified as obese
- 25.0-29.9kg/m^2 is overweight
- <18.5kg/m^2 is underweight
33
android obesity
- fat stored in the trunk or abdominal area
34
gynoid obesity
- fat stored around the hips and thighs
35
body composition
- % water and % mineral
- reference method for developing population-specific reference and formulas
- takes into account: age, sex, ethnicity
- population specific prediction equations do not exists for all age groups within ethnicities
36
essential fat
- needed for normal physiological function
- found within tissues such as muscles, nerve cells, cone marrow, intestines, heart, liver, and lungs
37
storage fat
- stored in adipose tissue
- subcutaneous fat: found just beneath the skin
- visceral fat: found around major body organs
- functions: stores calories when needed, releases hormones that control metabolism, helps in retaining body heat, acts as padding against physical trauma
38
skinfold method
- indirect measurement of subcutaneous body fat
- assumptions:
* good measure of subcutaneous fat
* distribution of subcutaneous and internal fat is similar for all of the same sex
* sum of SKF from multiple sites it used to estimate total body fat
39
Bioelectrical Impedance analysis
- non-invasive - indirect method of measuring FFM
- sensors are applied to the skin and a weak electrical current is run through the body to measure it's electrical resistance because fat is a less efficient conductor than lean tissue
- combination of pairs of sending and receiving electrodes
40
Dual-energy X-ray Absorptiometry
- three component (3C) model
- usual dual x-ray beam frequencies
- best method to see mineral contribution as well
- fasting prior to increases testing accuracy
41
Total energy expenditure (TEE)
- TEE = RMR + dietary thermogenesis + EAT + NEAT
- EAT: exercise activity thermogenesis
- NEAT: non-exercise thermogenesis
42
how large of a calorie deficit is needed to lose 1lb
3500 kcal
43
FITT principle
- used for training load
- F: Frequency
- I:Intensity
- T:Time
- T:Type
44
Eight principles of training
1. overload
2. Recovery
3. Supercompensation
4. progression
5. specificity
6. reversibility
7. individual needs
8. variation
45
ATP
- adenosine triphosphate
- the energy currency of life and movement
- constantly broken down and created
46
the PCr system
- ATP generation by ADP receiving a P from phosphocreatine
- very fast, low capacity
47
the glycolitic system
- ATP generations through anaerobic glycogenolysis and glycolysis
- quite fast, medium capacity
- results in high lactate, low pH in muscle - unsustainable
- produces lactate and H+
- takes place in the cytoplasm/sarcoplasm
- conversion of one molecule of glucose of two molecules of lactate
48
the aerobic/oxidative system
- ATP generation through oxidative phosphorylation in mitochondria
- slow, high capacity
- sustainable
49
what limits the rate of ATP production in the oxidative system
1) mitochondrial capacity
2) rate of oxygen delivery
3) rate of substrate provision
50
how long does it take for the PCr to get depleted
- 10-15s of all out exercise
51
what is the glycolytic capacity
- threefold higher
- lasts 30-90s
- not limited by glycogen availability but instead by increasing intramuscular acidity
52
Measuring energy expenditure
- can be done by measuring heat lost
- direct - sealed chamber
- indirect - o2 consumption and CO2 production
* 5 kcal/L of O2 consumed
53
carbohydrates as fuel
- all carbs are eventually converted to glucose (6-carbon sugar)
- at rest, carb is stored in muscle and liver in the form of glycogen
54
fat as fuel
- main source during prolonged and low-intensity exercise
- adults with more fat can carry more energy thi sway, while carb stores cannot go up
- fat metabolism yields (9.4 kcal/g)
- free fatty acids are the only one that can be used for energy
55
protein as fuel
- up to 10% of energy during prolonged exercise
- can only be used during severe starvation
- must be converted into glucose (gluconeogenesis) or FFA (lipogenesis)
- produces 4.1 kcal/g
56
functions of the spinal cord
- delivers motor commands, returns information from the periphery and coordinates reflexes
1) motor nerves (efferent)
* pyramidal tract (voluntary movements)
* 31 pairs of spinal motor nerves (8 cervical, 12 thora coccygeal)
2) sensory nerves (afferent)
3) interneurons
57
motor unit
- makes up the functional unit of the movements
- consists of an alpha motoneurons and the specific muscle fibers that it innervates
- all or none principle
58
Epimysium
- connective tissue that surrounds the entire muscle tissue
59
perimysium
connective tissue surrounding a bundle of muscle fibers
60
endomysium
a network of connective tissue which surrounds individual muscle fibers
61
fasicle
a group of muscle fibers is bundled as a unit within a muscle
62
sarcolemma
the plasma membrane of the muscle cell
63
sarcomere
basic contractile unit of a muscle fiber
64
what is the structure of muscle fiber
- each muscle fiber is a very specialized cell
- multiple nuclei
- fibers packed with myofibrils
- volume of myofibrils is 80-85%
- mitochondria is %5 and up to 10% in trained individuals
65
define neuromuscular fatigue
- failure to maintain the required force during a given task
66
Maximal Voluntary Activation (MVA)
- maximal force from your central nervous system and your muscles
- cannot tell us whether the deficit is in the brain or the muscle
67
which intensity of exercise causes peripheral and central fatigute
- higher intensity results in more peripheral fatigue
- lower intensity results in more central fatigue
68
capacity of PCr
- depends on the resting content
- takes 10-15s of all out exercise
69
factors affecting PCr content
- muscle PCr content appears to be unresponsive to training
- dietary intake or creatine does make a difference
70
why does glycolysis slow down
- 30 second spring can break down 25% of glycogen (more in type II fibers)
- glycogen depletion is typically not considered the main reason for glycolysis slow down
- glycogen is resynthesized again during recovery
- ANSWER: phosphofructokinase (PFK) enzyme that limits the rate
71
lactate transport
- transported out of cells through monocarboxylate (MCT1 and MCT4)
- MCT4 is abundant in cells that have high rates of glycolysis (type II muscle fibers)
- MCT1 transporters are abundant in cells importing lactate for oxidative phosphorylation
- Lactate- and H+ are co-transported by MCT
72
buffer systems in blood
- vigorous exercise can cause the pH of the body to fall below 7 instead of its regular 7.4
- this requires the carbonic acid-bicarbonate buffer system in blood to buffer the acidity
73
buffering in muscle
- capacity is increased through high intensity training
- caropsine content also impacts buffereing capacity
- phosphate buffering system is the most important followed by the buffering provided by proteins
74
