Physiology Flashcards
(216 cards)
1
Q
Term for EE above resting rate post exercise?
A
EPOC/Excess post-exercise oxygen consumption
2
Q
What is relative VO2max?
A
Total volume of oxygen consumed related to body weight (in kg)
3
Q
Formula for calculating VO2max?
A
Relative VO2max = L/min x 1000 divided by body weight
4
Q
Why is it important to measure EE?
A
Your diet revolves around the things you do everyday
5
Q
Why is it good to eat a decent amount of carbs and protein post-workout?
A
Stimulates MPS, improves recovery and enhances the quality of the next workout
6
Q
Minutes of aerobic activity recommended per week for 18-65 year olds?
A
150 mins moderate/75 mins vigorous/equivalent combinations of both
7
Q
Formula for calculating respiratory exchange ratio?
A
RER = VCO2 produced divided by VO2 consumed
8
Q
Oxygen (L/min) needed per min to satisfy resting energy requirements?
A
0.2-0.35 L/min
9
Q
Formula for calculating METs?
A
METs x 3.5 x Body Weight (kg) divided by 200 = kcal/min
10
Q
What is the equivalent of foodstuff + oxygen?
A
Water + CO2 + ATP + Heat
11
Q
What units can energy be reported in?
A
Joule (J) & kilocalorie (kcal)
12
Q
What are the main purposes of energy?
A
Growth, repair, digestion, and storage
13
Q
What is the 1st law of thermodynamics?
A
Energy can be changed from one form to another, but it cannot be created or destroyed
14
Q
What is 1kcal in Joules?
A
4186J
15
Q
What is the ratio of CO2 expired to O2 consumed at the level of lungs?
A
The respiratory exchange ratio
16
Q
What is the average total metabolic rate of an individual engaged in normal daily activities?
A
1800-3000kcal
17
Q
What is direct calorimetry?
A
The measurement of heat production from an individual, in calories, when placed in an insulated chamber.
18
Q
Where does direct calorimetry usually take place?
A
In a professional medical setting and on a treadmill.
19
Q
How is the volume of oxygen consumed measured in direct calorimetry?
A
Measured through the exhaled air.
20
Q
How is heat production measured in direct calorimetry?
A
The temperature of water (which travels through the room via pipes) is measured before and after the subject enters the room.
21
Q
What are the limitations of direct calorimetry?
A
- A small percentage of heat will be lost by friction
- A small percentage of heat will still be stored in sweat molecules
- The method wouldn’t be relevant to measuring EE of stop/start sports
22
Q
What is indirect calorimetry?
A
The method by which measurements of the RER are used to estimate the EE.
23
Q
What is the principle of indirect calorimetry?
A
Energy releasing reactions in the body depend upon oxygen utilised and carbon dioxide produced.
24
Q
What is the assumption of indirect calorimetry?
A
Rate of oxygen and carbon dioxide exchanged in the lungs = Rate of usage and release by body tissues.
25
What is an example of indirect calorimetry?
Spirometry
26
What is closed circuit spirometry?
1. ) Subject inhales via a face mask from a container full of oxygen.
2. ) Exhaled air goes back to the container via soda lime, which absorbs CO2.
3. ) This changes the volume of oxygen in the container and is recorded as volume of oxygen consumed.
27
Equipment for open circuit spirometry?
- Treadmill
- Low resistance 2 way valve
- A nose clip
- Low resistance falconia tubing
- Douglas bag
28
What is meant to occur in open circuit spirometry?
- Exhaled oxygen = decrease
- CO2 = increase
- Nitrogen = stays at a similar percentage compared to inhalation
29
Why isn't all oxygen used up in spirometry or exercise?
Oxygen still provides for other bodily functions, such as the function of your organs, and cannot all be used for exercise
30
What is the oxygen consumption formula? Units?
Volume of oxygen in - Volume of oxygen out = Oxygen consumption (VO2) (L/min)
31
What is VO2? VCO2?
```
VO2 = Oxygen consumption
VCO2 = Carbon dioxide output
```
32
Other terms/abbreviations for carbohydrates?
- CHO
| - Glucose
33
What factors influence energy expenditure?
- Gender
- Age
- Body mass
34
What is ATP?
- Adenosine Triphosphate
| - Important to all life as it stores and releases energy for many cellular processes
35
What does a fixed amount of energy expenditure always produce?
A fixed amount of heat
36
Ways of measuring energy expenditure?
- Amount of movement
- Weight gain/loss
- Calorimetry
37
Source of recommended activity guidelines? Year?
Gary O'Donovan, Journal of Sport Sciences, 2010
38
What RER suggests that fat is the predominant source fuel? Carbs?
- Fat = 0.7
| - Carbs = 1.0
39
What are the names of the key connective tissue in muscle?
```
Epimysium
Perimysium
Fascicle
Endomysium
Muscle cell
```
40
What is epimysium?
The connective tissue around muscle
41
What is total muscle?
Groups of fascicles
42
What is perimysium?
The connective tissue around fascicles
43
What are fascicles?
Groups of muscle cells
44
What is endomysium?
The connective tissue around muscle cells
45
What are muscle cells?
The cells that make up muscle
46
Easy sentence to remember the structure of muscle?
Even Pulis Finds Emery Mad
47
3 key features of skeletal muscle?
1. ) Movement of skeleton
2. ) Under voluntary control
3. ) Rapid and forceful contractions for short durations
48
What is a sarcomere?
The functional unit of striated muscle (the most basic unit that makes up our skeletal muscle).
49
How many different parts does the sarcomere have? Names?
5 parts:
1. ) A Line
2. ) H Line
3. ) I Line
4. ) M Line
5. ) Z Disc
50
Easy sentence to remember the structure of a sarcomere?
I must have a zebra
51
What is the A Line in a sarcomere?
Thick filaments (myosin) length
52
What is the H Line in a sarcomere?
Thick filaments (myosin) but no thin filaments (actin)
53
What is the I Line in a sarcomere?
Thin filaments (actin) but no thick filaments (myosin)
54
What is the M Line in a sarcomere?
Supporting proteins holding the thick filaments (myosin) in place
55
What are Z Disc's?
Defines the boundaries of an individual sarcomere
56
What are the 5 key ingredients required for muscle contraction?
1. ) Action potential
2. ) Calcium
3. ) ATP
4. ) Actin
5. ) Myosin
57
First step of the sliding filament theory?
Action potential causes the release of calcium from the sarcoplasmic reticulum.
58
Where is calcium stored?
In the sarcoplasmic reticulum
59
Chemical name/abbreviation for calcium?
Ca2+
60
Chemical name/abbreviation for inorganic phosphate?
Pi
61
What is troponin?
Protein in muscle fibres that help to regulate muscle contraction.
62
What is actin?
The thin filaments in a sarcomere
63
What is myosin?
The thick filaments in a sarcomere
64
4 key steps for initiating a contraction?
1. ) A stimulus to the skin is received by a sensory receptor
2. ) The action potential travels through sensory neurons to the CNS
3. ) The CNS interprets the information and the most appropriate motor response is derived
4. ) The motor action potential travels out from the CNS through motor neurons to the appropriate point
65
What are action potentials?
Nerve signals.
66
What is resting membrane potential?
The difference in sodium and potassium ions inside and outside a neuron (nerve cell) = -70mV (millivolts)
67
Chemical name/abbreviation for sodium?
Na+
68
Chemical name/abbreviation for potassium?
K+
69
Key parts of a neuron (nerve cell)?
- Cell Body
- Dendrites
- Axon
- Synaptic end bulb
70
How can you measure the voltage across a neuron (nerve cell)?
Using a voltmeter
71
What happens to a neuron (nerve cell) when a stimulus occurs?
- Sodium (Na+) moves into the cell and Potassium moves out
| - Inside of the cell becomes less negative
72
What is depolarization?
When the inside of a neuron (nerve cell) becomes less negative due to a stimulus
73
What happens when you get a depolarization greater than or equal to 15-20 mV?
- Threshold occurs
| - Action potential is generated
74
How is action potential generated?
1. ) -70mV is the resting membrane potential
2. ) If the stimulus is sufficient to cause a depolarization greater than or equal to 15-20 mV (e.g. membrane potential becomes -55mV to -50mV) threshold occurs
3. ) Action potential is generated
75
How does depolarization occur?
1. ) Voltage gated sodium channels open after a stimulus
2. ) Rapid sodium entry into the neuron occurs, making the inside less negative
3. ) Voltage gated potassium channels open
4. ) Potassium leaves the neuron to the outside extra cellular fluid
76
What are voltage gated sodium/potassium/calcium channels?
Small compartments on the membrane of a neuron (nerve cell) which allow the movement of sodium/potassium/calcium in/out of the cell
77
What occurs after depolarization in a neuron (nerve cell)?
1. ) Voltage gated potassium channels remain open after depolarization allowing additional potassium to leave the neuron (nerve cell) = hyperpolarization
2. ) Eventually the channels close
3. ) Less potassium leaves the cell
4. ) Sodium is pumped out of the cell
5. ) Cell returns to its resting membrane potential
78
What is hyperpolarization?
When additional potassium leaves a neuron (nerve cell) due to the voltage gated potassium channels remaining open after depolarization
79
Where does action potential move to and from along a nerve cell?
Axon hillock to the axon terminal
80
What is the term for the process of a substance being produced and discharged by a cell?
Secretion
81
What is the term for the process of action potential moving from one node of ranvier to the next?
Saltatory conduction
82
What separates each node of ranvier along a neuron (nerve cell)?
Myelin sheath
83
What is the myelin sheath?
A waxy substance secreted by the schwaan cell that separates the nodes of ranvier
84
What are the nodes of ranvier?
The regions of the cell where there is no myelin sheath
85
What is the schwaan cell?
A cell that secretes myelin sheath
86
How does action potential move along a neuron (nerve cell)?
- Opening of the voltage gated sodium channels
- Action potential develops as an electrical impulse
- Action potential jumps from one node of ranvier to the next
87
Where does action potential specifically move to and from when moving from nerve to muscle?
From the cell body to the motor end plate
88
Where does the nerve cell come into very close contact with the muscle cell?
Motor end plate
89
What happens when action potential as an electrical impulse reaches the motor end plate?
- Voltage gated calcium channels open
| - Calcium moves into the cell
90
What happens when calcium moves into the neuron (nerve cell)?
1. ) Vesicles containing acetylcholine fuse with the end of the nerve cell
2. ) Acetylcholine releases into the gap between the nerve cell and muscle
3. ) Acetylcholine attaches to the surface of the muscle cell
91
What happens when acetylcholine attaches to the surface of the muscle cell?
1. ) Causes gates on muscle cell to open and sodium rushes in
2. ) AP then passes through the muscle cell and calcium is released from the sarcoplasmic reticulum
92
What happens when AP passes through the muscle cell and calcium is released from the sarcoplasmic reticulum?
1. ) Causes a change in actin allowing binding to occur
| 2. ) Allows the sliding filament theory to occur thus leading to muscle contraction
93
What is a neurotransmitter?
A group of chemical substances released by neurons to stimulate other neurons or muscle or gland cells
94
How fast does action potential travel through a neuron (nerve cell)?
119m/s
95
What is multiple sclerosis?
- Autoimmune disease that attacks myelin sheath causing scarring
- This results in the slowing/blocking of action potential
96
What is demyelination?
Any condition that attacks myelin
97
What is sclerosis?
When the myelin sheath is scarred
98
What is a muscle biopsy?
- A method of examining an individuals fibre types
1. ) A small device plunged into muscle, removing a sample of it
2. ) It is then frozen, sliced up, stained, and looked at under a microscope
3. ) Type 1 appears black, type 2a = white, type 2x = grey
99
What are type 1 muscle fibres?
Slow twitch muscle fibres
100
What are type 2 muscle fibres?
Fast twitch muscle fibres
101
What determines fibre type?
Fibre type depends upon the nerve (motor) that innervates the fibres
102
What are the characteristics of type 1 fibres?
- High oxidative capacity
- Low glycolytic capacity
- Slow contractile speed
- High fatigue resistance
- Low motor unit strength
103
What are the characteristics of type 2 (x) fibres?
- Low oxidative capacity
- Highest glycolytic capacity
- Fast contractile speed
- Low fatigue resistance
- High motor unit strength
104
What is a motor unit?
Term to describe a group of muscle fibres controlled by a single nerve
105
Which fibre type means that the motor nerve fires at a low frequency?
Slow twitch/type 1
106
Which fibre type means that the motor nerve fires at a high frequency?
Fast twitch/type 2
107
Why is power greater in type 2 muscle fibres for the same absolute force?
1. ) Velocity is 5-6 times greater
2. ) Fast form of myosin ATPase, therefore faster cross bridges are formed
3. ) More developed SR, therefore greater storage of calcium and a faster release of it
108
Formula for power?
Power = Force x Velocity
109
What is myosin ATPase?
The enzyme that helps break down ATP in the myosin head
110
What are enzymes?
Proteins that speeds up the rate of a chemical reaction in a living organisms
111
Why is force 10-20% greater in type 2 fibres?
1. ) Larger, therefore more myosin cross-bridges per unit CSA
2. ) Motor nerve excite >300 fibres whereas type 1 = <300
112
CSA?
Cross sectional area
113
What does the level of force a muscle produces depend upon?
1. ) Number and type of motor units recruited
2. ) Firing frequency of each motor unit
3. ) The size of muscle
4. ) Speed and type of contraction
5. ) Sarcomere length
114
Why is there an optimal sarcomere length for force production? (Person and year?)
There is an optimal overlap between thick (myosin) and thin (actin) filaments. (Macintosh, 2006)
115
When do we get maximum force?
When there is maximum cross-bridge formation being able to generate force
116
When does maximal isometric force occur?
At zero velocity
117
What happens as the velocity of concentric contraction increases?
Force generation decreases
118
What is a reason for force generation decreasing as the velocity of contraction increases?
As the velocity is increasing, there is insufficient time for myosin and actin to form cross bridges during force
119
What happens as the velocity of eccentric contraction increases?
Force generation increases
120
What is a reason for force generation increasing as eccentric contraction increases?
Increased number of cross bridges attached to actin, increased actin/myosin interactions generating more force
121
In what way are muscle fibres recruited?
During a physical task according to their size, in this order:
1. ) Type 1/Slow twitch
2. ) Type IIa
3. ) Type IIx
122
In what pattern does the blood flow through the heart?
Cycle of down, up, down, up
123
How does deoxygenated blood travel DOWN the heart?
1. ) Superior vena cava
2. ) Right atrium
3. ) Tricuspid valve
4. ) Right ventricle
124
How does deoxygenated blood travel UP the heart?
1. ) Pulmonary semilunar valve
| 2. ) Pulmonary artery
125
What does blood do after it travels through the left pulmonary artery?
Picks up oxygen from the lungs
126
How does oxygenated blood travel DOWN the heart?
1. ) Pulmonary vein
2. ) Left atrium
3. ) Mitral (biscupid) valve
4. ) Left ventricle
127
How does oxygenated blood travel UP the heart prior to around the body and before the cycle repeats itself?
1. ) Aortic semi-lunar valve
| 2. ) Aorta
128
What is the whole heart known as? What does it mean?
Myocardium:
- Myo = muscle
- Cardium = heart
129
Which part of the myocardium divides the two ventricles?
Interventricular septum
130
Cardiac structure? (outside to inside)
1. ) Fibrous pericardium
2. ) Pericardium
3. ) Pericardial cavity
4. ) Epicardium
5. ) Myocardium
6. ) Endocardium
7. ) Heart chamber
131
What is the role of the pericardial cavity?
To allow the expansion and contraction of the heart
132
3 layers of the heart which classify as the 'heart wall'?
1. ) Epicardium
2. ) Myocardium
3. ) Endocardium
133
How does blood travel AWAY from the heart?
Through the pulmonary artery
134
How does blood travel TOWARDS the heart?
Through the pulmonary vein
135
What is the biggest chamber of the heart?
Left ventricle
136
When does the first heart sound occur?
When the atrioventricular valves close and the semilunar valves open
137
When does the second heart sound occur?
When the semilunar valves close and the semilunar valves open
138
What does systole mean?
Contraction of`
139
When is the atria relaxed?
During the ventricular systole & diastole phase
140
What does diastole mean?
Relaxation of
141
What happens during phase 1 of the Wiggins diagram?
Rapid ventricular filling:
- Mitral valve opens
- Zero aortic blood flow
142
What happens during phase 2 of the Wiggins diagram?
Rapid ventricular filling begins to slow down:
- Mitral valve still open
- Still zero aortic blood flow
143
What happens during phase 3 of the Wiggins diagram?
Atrial systole occurs:
- Still zero aortic blood flow
- Ventricles are full of blood and pressure starts to build
144
What happens during isovolumetric contraction? (Phase 4 of Wiggins diagram during ventricular systole)
1. ) Mitral valve closes and ventricular pressure increases as its full of blood
2. ) Aortic valve opens
145
What happens during rapid ejection? (Phase 5 of Wiggins diagram during ventricular systole)
Blood flows out at a high pressure thus ventricular volume decreases and aortic blood flow increases
146
Another term for aortic blood flow?
Ventricular outflow
147
What happens during reduced ejection? (Phase 6 of Wiggins diagram during ventricular systole)
- Blood is released at a reduced rate
- Left ventricular pressure decreases
- Aortic blood flow decreases
148
What happens during isovolumetric relaxation? (Phase 7 of Wiggins diagram during ventricular systole) (Final phase)
- Left ventricular pressure continues to decrease
- Aortic blood flow returns to zero as the aortic valve closes
- Ventricular volume plateaus
149
2 key terms for intrinsic cardiac stimulation?
1. ) Autorhythmic
| 2. ) Myogenic
150
What does Autorhythmic refer to?
The heart maintains its own pulse rate.
- External control dictates the change in pulse rate
- Without external stimulus pulse rate would be 100bpm
151
What does Myogenic refer to?
The heart acts as its own conduction system as the cardiac cells are able to conduct electrical stimulation, and activate the cardiac muscle cells in a particular pathway
152
How is the heart Autorhythmic?
1. ) The sinoatrial node, located at the top right atria stimulates the atria and makes it contract.
2. ) It then sends a signal to the atrioventricular node, located between the aria and ventricles in the middle of the heart.
3. ) The atrioventricular node then sends an electrical impulse around the ventricles initiating their contraction, sending blood through the body.
153
2 types of extrinsic cardiac control?
1. ) Parasympathetic
| 2. ) Sympathetic
154
What is the role of the parasympathetic nervous system?
The slowing of the heart, hyperpolarising autorhythmic fibres.
155
What is the vagus nerve?
Part of the PNS.
| Decreases heart rate and force of contraction.
156
What does PNS mean?
Parasympathetic nervous system.
157
What does SNS mean?
Sympathetic nervous system.
158
What is the role of the sympathetic nervous system?
To increase HR and force of contraction due to a stress stimulus, through depolarising autorhythmic fibres.
159
How does the SNS increase BPM?
Uses either:
The sympathetic cardiac nerve to act on the SA node or the AV node.
Through catecholamines.
160
What are cathecholamines?
Adrenaline.
161
What does 'hyperpolarisation' mean?
A less polarised state making it harder for a contraction to occur
162
What does 'depolarisation' mean?
A more polarised state making it easier for a contraction to occur.
163
What type of control is the heart under when your HR is BELOW 100bpm? Through what?
Under parasympathetic control through the vagus nerve
164
What type of control is the heart under when you HR is OVER 100bpm? Through what?
Under sympathetic control through sympathetic fibres and cathecholamines
165
What does 'polarisation' refer to?
The level of charge a nerve fibre has.
166
What happens to nerves millivolts when depolarisation occurs?
The level of charge goes closer to zero from -70mv.
167
What happens to nerves millivolts when repolarisation occurs?
The level of charge increases/decreases AWAY from zero.
168
What happens to nerves millivolts when hyperpolarization occurs?
Decreasing level of charge.
169
Hyperplasia?
An increase in the number of cells within a muscle associated with maturation.
170
Statural/incremental growth?
Body mass increases in size and length.
171
What is statural/incremental growth due to?
An increase in the length of bones.
172
Where do the cells involving growth habituate?
Epiphyseal plate.
173
When does growth stop?
When your epiphyseal plates fuse and create solid bone.
174
3 types of growth?
1. ) Statural/incremental growth.
2. ) Hypertrophic growth.
3. ) Reparative growth.
175
Hypertrophic growth?
Body mass increases in response to functional demands.
176
Reparative growth?
Structural maintenance of tissue and repair of damaged tissues.
177
3 stages of growth & development?
1. ) Infancy.
2. ) Childhood.
3. ) Adolescence.
178
When does a very rapid rate of growth and improved neuromuscular co-ordination occur?
During infancy.
179
How long does the infancy period last for?
1 year.
180
When does a steady rate of growth and maturation with large increases in motor co-ordination occur?
Childhood.
181
When is the childhood period?
Junior school years.
182
When does the growth spurt and puberty phase occur?
During adolescence.
183
Until around what age do boys and girls grow at a similar rate?
8.
184
When does peak height velocity occur in girls?
8-12 years.
185
When does peak height velocity occur for boys?
12-15 years.
186
What factors regulate growth?
Hormones.
| Environmental factors.
187
What does the growth hormone affect the most?
Long bones.
188
Which hormone tends to turn off the epiphyseal plates causing bones to fuse?
Oestrogen.
189
Do men or women produce more oestrogen?
Women.
190
What environmental factors up regulate GH, receptors and stimulate growth factors?
Moderate exercise.
| Proper nutrition.
191
What environmental factors can impair growth?
Excessive exercise.
| Inadequate caloric intake.
192
Maturation?
The timing and tempo of the biological system as it matures.
193
What is the final period in the growth process leading to maturity?
Adolescence.
194
When does adolescence begin?
```
When you reach critical levels of:
Body fat.
Body mass.
Height.
Skeletal maturity.
```
195
When does adolescence occur for girls on average? Boys?
```
Girls = 10.5-13 years.
Boys = 12.5-15 years.
```
196
What happens to girls the earlier the onset of adolescence?
Rate of growth is faster the earlier the onset of adolescence.
197
What do female early maturers typically have?
Shorter legs.
| Narrower shoulders.
198
What is the typical growth (inches) for girls per year during adolescence?
3 inches per year.
199
What do male early maturers typically have?
Muscular short legs.
| Broader hips.
200
What is the typical growth (inches) for boys per year during adolescence?
4 inches per year.
201
What is considered a poor measure of "real" biological age?
Chronological age.
202
Most exercise performance indices are related to growth and maturation factors such as...?
Muscle mass.
Height.
Heart size.
Etc.
203
What types of body composition does maturation affect?
Fat tissue.
Bones.
Muscle.
204
How does hypertrophy/hyperplasia affect fat tissue throughout maturation?
```
Hypertrophy = Increase in fat cell size.
Hyperplasia = Increase in fat cell number.
```
205
How does bone growth occur during maturation?
Deposition/increase of minerals.
| Increasing number of cells.
206
How does muscle growth occur during maturation?
Hypertrophy.
207
Around what kg of fat free mass do boys/girls reach by adulthood?
```
Boys = 65kg.
Girls = 45kg.
```
208
Around what kg of fat mass do boys/girls reach by adulthood?
```
Boys = 10kg.
Girls = 15kg.
```
209
Around what fat % do boys/girls reach by adulthood?
```
Boys = 15%.
Girls = 25%.
```
210
What factors in children warrant special consideration in exercise testing and prescription?
Smaller stature.
Smaller body mass.
Immaturity of their physiologic systems.
211
At the ages of 5, 7, 9 and 11, what excess % of energy will children need in order to walk at the same speed as an adult?
```
5 = 37%
7 = 26%
9 = 19%
11 = 13%
```
212
Gait dynamics?
The way you walk.
213
Second step of the sliding filament theory?
Calcium binds to troponin, moves tropomyosin and reveals binding site on actin.
214
Third step of the sliding filament theory?
Myosin attaches to actin via cross-bridge and power stroke occurs due to the release of inorganic phosphate.
215
Myofibrillar ATPase?
Identifying fast and slow contracting muscle fibres.
216
Cross-bridge cycling?
Bridges constantly being formed and broken during muscle contraction.
