Final Exercise physiology deck Flashcards
Which equation below accurately represents the CO2 buffering equation at the lungs?
HCO3- + H+ = H2CO3 = CO2 + H20
What term is used to describe the blueish tinge tissue exhibits during hypoxia?
Cyanosis
Which of the following occur immediately when exposed to high altitude?
The ventilation rate increases
What distance above sea-level would be classed as ‘high’ altitude, where altitude sickness and acclimatisation become clinically relevant, and performance is considerably impaired?
3000 – 6000 meters
What is the average lactate concentration at rest?
1 mM
Which are the physical activity guidelines for children and adolescents?
A. 60 or more minutes of MVPA/day
The QRS complex represents
Ventricular depolarization
Where is the electrical activity of the heart generated?
Sinoatrial node
How does the process of aging affect VO2max in adult men and women?
It declines approximately 1% per year and occurs twice as fast in sedentary compared to physically active
Men and women attain their highest bone mass levels between the ages…?
20-40
What percentage of our vitamin D comes from the sun?
90%
What is the amino acid precursor to dopamine?
Tyrosine
List some of the key physiological changes that occur with age?
40% decline in spinal cord axons
10% decline in nerve conduction velocity, due to structural changes in myelinated neurones, resulting in increased internal distances, decreasing signal jumping over Schwann cells
Also a loss of fastest conducting axons and decrease in soma size
It declines approximately 1% per year and occurs twice as fast in sedentary compared to physically active (VO2)
Bone mass decreases after 40
Explain the topic of altitude sickness?
Acute altitude sickness ‣ Headache ‣ Nausea ‣ Fatigue ‣ Causes Ascending faster than 500m/d
high altitude pulmonary oedema:
develops 2-3 days when higher than 2500m
Can be fatal within hours
Accumulation of fluid in the lungs that prevents air spaces from opening up and filling with fresh air with each breath
bad coughing symptoms
high altitude cerebral oedema:
An increase in blood flow to the brain is a normal response to low oxygen levels, as needs to maintain the oxygen to the brain. However, if the blood vessels in the brain are damage fluid may leak out and result in death
What’s the ventilatory threshold?
The point at which pulmonary ventilation increases disproportionately with oxygen consumption during graded exercise
Figure
VO2 on the x axis (VO2 ml.min^-1) up to 4500
VCO2 on the y axis (ml.min^-1) up to 6000
Draw one line with not that steep gradient
Draw one with a steeper gradient further on and crossing over
Label crossing over point as ventilatory threshold
Calculations for Oxygen carrying capacity of blood?
Units are ml per litre of blood
{O2} = ({HB} x 1.34 x 0.97) + (PO2 x 0.003)
{HB} = males 150g/1L, females 130g/1L
PO2 = 100
- 34 represents ml O2 g Hb
- 97 represents 97% saturation
- 003 represents O2 solubility
If asked:
Total = both sides of the equation
Toddler activity guideline?
Physically active daily for at least 180 minutes (3hours), spread throughout the day.
‣ All under 5s should minimise the amount of time spent being sedentary (being restrained or sitting) for extended periods.
Equation for CO2 + H2O to HCO3- and it relating to chloride shift?
takes place when the blood gives up oxygen and receives carbon dioxide.
CO2 + H2O = (via carbonic anhydrase) H2CO3 = H(+) + HCO3-
HCO3- leaves the red blood cell, Cl- moves in to restore charge
Ficks law of diffusion?
THE RATE OF GAS TRANSFER IS PROPORTIONAL TO THE TISSUE AREA, THE DIFFUSION COEFFICIENT OF THE GAS, AND THE DIFFERENCE IN PARTIAL PRESSURE OF THE GAS ON THE TWO SIDES OF THE TISSUE, AND INVERSELY PROPORTIONAL TO THE THICKNESS
V GAS = ((P1-P2) x A x D)) / T
What is Boyle’s Law?
Pressure of a gas in a closed container inversely proportional to volume of container at a constant temperature
P1V1 = P2V2
What is Henry’s law?
When a mixture of gas is in contact with a liquid each gas dissolves in the liquid in proportion to it’s partial pressure and solubility until equilibrium is achieved and the gas partial pressure are equal in both locations
Solubility is constant
Pressure gradient is critical - gas diffuse from high pressure areas to low pressure areas
What is Daltons law
Dalton’s law of partial pressures states that the total pressure of a mixture of gases is the sum of the partial pressures of its components: P Total = P gas 1 + P gas 2 + P gas 3 .
- Describe the changes in neural function with training and age?
40% decline in spinal cord axons
10% decline in nerve conduction velocity, due to structural changes in myelinated neurones, resulting in increased internal distances, decreasing signal jumping over Schwann cells
Also a loss of fastest conducting axons and decrease in soma size
Resistance training can reduce it by increasing muscle hypertrophy
What is voluntary activation and the formula?
The level of neural drive to muscle during exercise
estimated by interpolation of a single supramaximal electrical stimulus to the motor nerve during an isometric voluntary contraction
(%) = (1 –a/b) × 100
Human breathing?
Accessory muscles
Diaphragm 75% (in the exam)
Intercostal muscles
Abdominal muscles
Steps of Inhalation:
Diaphragm flattens
External intercostals Up and Out, causing elevation of ribs
Increase Volume
Decrease Pressure
Air rushes in
Steps of exhalation at rest:
Passive process
Elastic recoil
Decrease Volume
Increase pressure
Air forced out
During exercise:
Becomes an active process
Muscles used are the internal intercostals, external obliques, rectus abdomens, transverse abdominus
Acute and prolonged affects of altitude?
Immediate response to increased altitude:
Hyperventillation
Increase in blood flow
Resting system blood pressure increases
Increase in sub maximal blood flow compensates for arterial
EPO concentrations rapidly increase, then goes back to normal
Longer term response to increased altitude:
Increased blood O2 carrying capacity:
Initial decrease in plasma volume
So increase in RBC concentration and Hb synthesis
Wilkerson et al (2017) notes for exam?
8 well trained male cyclists completed 2 50 mile TT
One after consuming nitrate rich beetroot juice, and one after consuming a placebo
BR elevated plasma Nitrate and reduced completion time by 0.8% which wasn’t statistically significant
Problems:
trying to answer does Nitrate supplementation work in longer races as well as does it work in better trained athletes
In pre lab they only did a 10 mile TT for familiarisation which isn’t the same as the 50 Mile tested,
Good things:
0.8% valid in competition
identify responders and non responders to the beetroot juice
Further study:
Use an optimal nitrate loading regimen
Further supplementation eg during
At least one proper familiarisation trial conductied
Ecological validity would be improved by completing the TT on the road, even though this is conflicted by weather
What is tidal volume?
Amount per breath
Breathing frequency?
Number of breaths
How to work out alveolar ventilation?
0.7 x tidal volume
How to work out dead space ventilation?
0.3 x tidal volume
What is inspiratory reserve volume?
Maximum volume of air that can be inhaled (from top of tidal volume on graph)
What is Expiratory reserve capacity?
Maximum volume of air that can be voluntarily exhaled (from bottom of tidal volume on graph)
What is residual volume?
Volume of air remaining in the lungs after maximal exhalation
What is vital capacity?
Maximum volume that can be inhaled and exhaled (IRV + Tidal volume + ERV)
What is FRC functional residual capacity?
Volume of air present in the lungs at the end of passive expiration (ERV + RV)
What is the respiratory muscle metaboreflex?
Fatiguing contractions of the diaphragm expiratory and and accessory respiratory muscles
Increase in reflex activating metabolites
Increase in group III/IV phrenic afferent (up to the brain) discharge
Brain says:
sympathetic efferent discharge, limb vasoconstriction and locomotor muscle fatigue
And decrease O2 transport to the limbs of the working muscles
Question on T and Z scores on bone mass?
-1 to -2.5 = low bone mass
smaller than - 2.5 = osteoporosis
T looks at the small group
Z looks at the whole population
T scores used for bone density
(X - Xbar) / standard deviation
DXA or QUS
Health of the bone is assed by biochemical markers, calciotrophic hormones and it’s rate of collagen synthesis
How to draw the flow volume question?
y axis is flow goes positive and negative, y axis is labelled flow, positive is +ve = expiration, negative is -ve = inspiration
Volume is on the x axis, make sure at the end there is space for the residual volume (0-2), then go up to 6
Triangle with semi circle on bottom, it reaches the y axis
Obstructive lung condition = right side of the triangle slopes down
Restrictive is the same but smaller
Exercise induced asthma the same but keeps getting smaller over time (smaller triangles)
Total lung capacity =?
ERV + Tidal Volume + IRV + residual volume
Inspiratory capacity = ?
IRV + Tidal volume
Minute ventilation?
Breathing rate x tidal volume
Lactate threshold and turning point on a graph?
lactate threshold - The first increase above baseline
Lactate turn point - When there is a sudden increase in Lactate
Draw on graph:
x axis pace 0mph to 15 mph
Lactate on y 0mmol to 10 mmol
Small increase around 8 mph mark with little pointers, then a large exponential increase at 10 mph = lactate turning point
What is VO2?
The difference between volume of gas inhaled and volume of gas exhaled per unit of time
VO2 = {(VI x Fio2) - (Ve x Feo2)} / T
The gold standard aerobic fitness test, used extensively in the assessment of athletes and research.
Underpinned by Fick equation
the maximum or optimum rate at which the heart, lungs, and muscles can effectively use oxygen during exercise, used as a way of measuring a person’s individual aerobic capacity at sea level
Measured by an exercise graded test
Achievement of ‘plateau’ of oxygen consumption
RPE > 17
What’s in the alveoli?
Type 1 cell: More numerous, enable gas exchange
Type 11 cell: Produce surfactant prevents lungs collapsing
Whats are the respiratory control centres in the brain?
Pons:
Apneustic area
Pneumotaxic area
Medulla Rhythmicity area:
Ventral and Dorsal group
More features of the pons?
Apneustic area:
Prolonged and slow rate of breathing
Overridden by pneumotaxic
Features of the pneumotaxic area?
Inhibitory impulse, limits duration of breath in
Breathing becomes faster by limiting breathing in
More features of the medulla oblongata?
Rhythmicity area:
Controls basic rate of breathing
Dorsal respiratory group - mainly inspiratory , can also talk to the ventral, but ventral can’t talk back
Ventral respiratory group
Features of the peripheral chemoreceptors?
Due to Glomus cells, which have K+ going in and out of them
If oxygen is down 60mmHg, the potassium channels close, so potassium builds up in the cell, calcium channels open due to increased voltage so calcium rushes in
Exocytosis of vesicles from cell which are filled with dopamine, which increases breathing rate
Cardiac conduction sequence?
Sinoatrial node
Current makes right atrium contract
Current goes to Bachmann’s bundle makes left atrium contract
Through septum of heart
Goes to atrioventricular node
His bundle
Purkinje fibers
Left posterior bundle and right bundle, ventricles contract
ECG wave?
P wave small hump - atrial depolarisation
QRS complex - down, large up, down, normal = ventricular depolarisation
T wave - small hump - ventricular repolarisation
QRS hides P wave repolarisation§
What is the FICK EQUATION?
Underpins VO2
VO2 (ml/O2/min) = Q (l.min^-1) x (CaO2 - CvO2)
Why is there increased extraction of O2 from the blood during exercise?
Sigmoid curve
Acidity, Pco2, 2,3-BPG, and temperature help remove oxygen
Acidosis increases during exercise, pH decreases, affinity of Hb decreases, more O2 delivered to acidic sites
Pco2 rises, affinity of Hb decrease, more oxygen delivered
BPG formed during glycolysis helps to unload by binding with Hb
Temperature increases affinity of Hb decreases, more O2 is delivered to warmed up muscle
Types of Axoplasmic transport?
They are moved along Microtubules (made of tubulin)
Anterograde transport the movement of molecules/organelles outward, from the cell body, due to Kinesin
Retrorade transport (toward the cell body) due to Dynein
What are Cholinergic neutrons?
Release Acetylcholine (ACh)
Equation for BMI?
Weight(kg) / Height^2 (m)
Physical activity guideline for adults?
2.5 hours a week
muscle work 2 times a week
Calculations for cardiac output?
Total volume of blood pumped by the ventricle per minute
Q (L.min^-1) = HR x SV
SV(ml) = EDV - ESV
so Q (L.min^-1) = HR x (EDV - ESV)
Calculations for blood pressure?
Mean arterial blood pressure = 2/3 DBP + 1/3 SBP
units are mmHg
Equation for find change of blood in arterial and Venus?
CaO2 - CvO2 = difference
Do arterial - however much oxygen is used
Units are ml of O2
Equation for running economy?
If not given VO2
VO2 (ml/Kg/Min) = 13.5(Speed (m\s)) - 8.5
If given speed in km/hr, /60 then /60 then x 1000
But if given Vo2 in ml/kg/min
O2 cost (ml/kg/km) = VO2 (ml/kg/min) / Speed (Km/hr) /60)
This is on the exam
Describe action potential?
-70mmv
Generated by SOPI pumps
Depolarisation occurs due to a stimulus
If hits -55mv, action potential generated, pushing us to + 30 mmv, as sodium channels open
Repolarisation, sodium channels close, potassium channels open goes down,
takes too long causing hyper-polarisation
Typical ECG response to exercise?
Minor changes in P wave form
Superimposistion of P and T waves of successive beats (starts to look like an “M”
Slight decrease in R wave amplitude
Q wave may be deeper
Increase in T wave amplitude
Minimal shortening of QRS complex
Depression of J point (the J point is found where the S wave makes its sharp deviation (right hand turn) toward the T wave
At rest the J point should come back to the isoelectric line
Rate related shortening of QT interval
Will be in exam
