Mid 2 Flashcards
Fick Equation
Relationship b/w Metabolism and Cardiovascular Function
1) VO2= Q (a-v)O2difference
2) VO2= HR x SV x (a-v)O2diff
Cardiac Output Measurement Equation
Q= HR x SV HR= BPM SV= mL
Dead Space- Anatomical vs. Physiological
space in the alveoli
Cardiac Output levels at Rest and Maximal Exertion
at Rest- 4 liters/ min (small person) to 6 liters/min (average) (can vary depending on person)
Maximal- Males 22 liters/min
Females 15 liters/min
Ejection Fraction (EF)
EF= SV / EDV
Averages 60% at rest
Proportion of blood pumped out of L ventricle w/ each beat.
- Common in older people, pumps more but less blood.
Systolic Blood Pressure
increases in direct proportion to the intensity of exercise
Diastolic Blood Pressure
Very Little change w/ exercise
Max Arterial Pressure (blood pressure)
1/3 (systolic- diastolic) + diastolic
Rate Pressure Product
SBP x HR
a Measure of myocardial workload
Factors Affecting Blood Flow
Pressure Gradient: 1 side vessel vs. another side.
HR & SV: + press. on that end.
Vessel Radius- ves. increase in size
Vessel length- travels more/ less
Viscosity of Blood- if blood is thicker it/w flow slower
Factors affecting Vessel radius
Oxygen level Temp. Changes CO2 levels Blood acidity adenosine levels CADET to the right
Hypertension
A SBP of ≥ 140, or a DBP ≥ 90 measured on at least 2 separate locations.
AHA Rec blood pressure levels
Normal: systolic & diastolic 100 or>
Effects of exercise on BP
Reduced resting catecholamine levels
Post exercise dilation of blood vessels
Possible lower blood sodium levels
Weight control
Maximal Oxygen Consumption (VO2 max)
VO2max= Q x a-vO2diff
A-VO2 difference
average A-VO2 difference is 15 @ max exercise
Increase fitness, assoc. w/ increase A-VO2 diff. due to better extraction of oxygen & better distribution of the blood.
Oxygen Utilization
Myocardium utlizes 70-80% of available O2 at rest and exercise
Karvonen
HRR (karvonen)
Target HR= [%exercise intensity x (HRmax - HRrest)] + HRrest
MAX HR
HRmax x % intensity= target HR
Limitations of HR
meds emotions temp humidity air pollution
Rating of perceived exertion
prescribe intensity monitor intensity RPE 12 to 16 -approx 40 to 84% HRR Use alone in conjunction with HR
cool down
reduce risk of cardio complications
gradually reduce intensity 5- 10 min
Allow HR and BP to return to Baseline or near
Prevents pooling of blood in extremities
reduce dizziness and fainting
time (duration)
-prescribe time and intensity to prop. stress cario resp system
ACSM rec:
30-60min moderate
20-60min vigorous
for a total of 150/week of moderate exercise or 75 of vig
increase exercise volume
no more than 10% per week
Aerobic training methods
continuous training
one contnnous exercise bout
Discontinnous training
several intermittent low to high intensity bouts interspersed w/ rest period
signs/symptoms of over training
mild led soreness general aches,
pains in muscles and joints,
washed-out feeling, tired, drained, lack of energy
sudden drop in ability to run normal distance or times
Fick’s Law
Rate of diffusion proportional to surface area, difference in partial pressure, inversely proportionate to membrane thickness
Ambient air
No2 79.04%
O2 20.93%
CO2 0.03%
Dalton’s law of total air pressure
P= PN2 + PO2 + PCO2
Ventilation/Perfusion ratio (V/Q)
Ideally 1.0
Rest or light exercise 0.8
maximal exercise 5.0
Gas Exchange
Pulmonary -lungs
Tissue- muscle etc.
gas exchange in alveoli
amtospheric PO2= 159mmhg
alveolarPO2= 105mmhg
Pulmonary artery PO2= 40mmhg
65mmhg (105mmhg- 40mmhg)
RBC
2,3 DPG is a byproduct of glycolysis in RBC’s, increased levels of reduce hemoglobin affinity for oxygen
Myoglobin
Bind O2 at Lower pressure Only 1 iron per molecule Binds 2 molecule of O2 Releases O2 to mitochondria PO2 is 1 - 2 mmhg
CO2 Transport
Dissolved in plasma 5%
Combined with HEM 20% (carbonemohemoglobin)
Combined w/ H2O
Carbonic acid (H2CO3)
Eventually Bicarbonate (HCO3) - loses 1 H from last step
Factors Controlling ventilation
at rest, PO2 & PCO2 (neurogenic factors)
in exercise, temp. pH, Neurogenic factors, Humoral, muscle and joint receptors.
Ventilatory Equivalent
20 to 25 L of air
1 L of O2
Energy cost of breathing
4% of total metabolism
40% of metabolism for person w/ (emphysema)
Smoking Exercise Capacity
Decrease max exercise capacity
Increase Resistance breathing
Increase time required to get steady state
appear more fit during submax testing
acid base regulation
Chemical bufferes
bicarbonate
phosphate
protein
respiratory Zone
large surface area
300 million alveoli
60- 80 Square meters
Inspiration
Diaphragm contracts and flattens out
external intercostals outside ribs pulling them over
Increased Vol of the chest
allows flow of air to lungs
Expiration
passive at rest
active during exercise or forced expiration
internal intercostils, abdominal muscles
Pulmonary Volumes and capacities
Tidal Volume (~0.5L) Inspiratory reserve (~3,0L) (IRV greater) Expiratory Reserve (~1.0L) (ERV less)
