1. Cardiovascular and pulmonary systems

2. Mid Session Quiz -25% Next week Will be on WebCT assessments
From 9 am 25/8/08  5 pm 29/8/08
Multiple choice and matching
Practice test (question types) up now, practice (content) on companion website for text.
Covers all lecture, lab, text and reading materials from weeks 1-5
Time limit = ½ hour
Grades will be released automatically
Contact me if tech problems

3. Today Cardiovascular Pulmonary System review
Acute adaptations to exercise
Chronic adaptations to exercise
Pulmonary

4. Major Cardiovascular Functions
Delivers oxygen to active tissues
Aerates blood returned to the lungs
Transports heat, a byproduct of cellular metabolism, from the body’s core to the skin
Delivers fuel nutrients to active tissues
Transports hormones, the body’s chemical messengers

5. CV system Consists of; Blood ~ 5L or 8% body mass Heart- pump
55% plasma
45% formed elements (99%RBC, 1%WBC)
Heart- pump
Arteries- High pressure transport
Capillaries- Exchange vessels
Veins- Low pressure transport

6. NEED TO KNOW
Heart
LHS pic (Blue) right atrium = deoxygenated blood returning from the body
 right ventricle  pumps it out the Pulmonary artery to lungs for aeration
Left Aorta recieves blood from the lungs, goes through to the left ventricle where it is pumped throughout the body
Atrioventricular valves ensure that blood movement is all one way RA RV = Tricuspid; LA LV = Bicuspid (Try before you buy)
Lub Dub, Lub Dub LUB is simultaneous contraction of both atria; Dub is simultaneous contraction of both ventricles
(70% of blood coming into atria actually flows into ventricels before contraction of atria)

7.
See blood flow through the heart

8. Peripheral Vasculature
Arteries
Provides the high-pressure tubing that conducts oxygenated blood to the tissues
Capillaries
Site of gas, nutrient, and waste exchange
Veins
Provides a large systemic blood reservoir and conducts deoxygenated blood back to the heart
WHY can we feel pulse through arteries and not veins? Arteries are pumping with heart beat. They contain layers of smooth muscle that constrict to regulate peripheral blood flow
Arterial walls are too thick to allow gaseous exchange this must happen in the capilliaries
Capillaries walls are thin enough to allow RBC through
Once O2 out and wastes in, blood is transported back to the heart through the veins
Veins  major structural component of the veins are their valves allows them to return the blood – milking- the way that we squeez a teat top to bottom

9. Valves prevent backflow of blood
B- shows one way flow of blood through the veins
Shows one way movement of the muscles assists with returning blood 
Constriction of smooth muscle bands successively along vein “Milking” or the way a snake swallows something

10. Blood Pressure Systolic blood pressure Diastolic blood pressure
Highest arterial pressure measured after left ventricular contraction (systole)
e.g., 120 mm Hg
Diastolic blood pressure
Lowest arterial pressure measured during left ventricular relaxation (diastole)
e.g., 80 mm Hg

11. BP changes with cardiac output- direct linear relationship, therefore as HR increases so does BP, systolic moreso than diastolic
WHY???
Systolic is the force of the contraction, which needs to increase to pump the blood around, whereas diastolic (relaxation) would not change much due to exercise

12. Changes for different types of exercise- why do you think resistance exercise has higher SBP???
Sustained muscular force compresses peripheral arterioles which increases resistance
Isometric exertion involves sustained muscle contraction against an immovable load or resistance with no change in length of the involved muscle group or joint motion.
Get someone to push against a wall
The result is a moderate increase in cardiac output, with little or no increase in oxygen consumption. Despite the increased cardiac output, blood flow to the noncontracting muscles does not significantly increase. This combination of vasoconstriction (the narrowing of blood vessels that restricts, or slows, the blood flow) and increased cardiac output causes a disproportionate rise in systolic, diastolic and mean blood pressures.

13. Heart Rate Regulation Cardiac muscle possesses intrinsic rhythmicity
Without external stimuli, the adult heart would beat at about 100 bpm

14. Regulation of HR Sympathetic influence Parasympathetic influence
Catecholamine (NE/E)
Results in tachycardia
Parasympathetic influence
Acetylcholine
Results in bradycardia
Cortical influence
Anticipatory heart rate
Heart rate is controlled by autonomic nervous system (ANS) which maintains homeostasis in the body. These maintenance activities are primarily performed without conscious control or sensation. The ANS has far reaching effects, including: heart rate, digestion, respiration rate, salivation, perspiration, diameter of the pupils, micturition - (the discharge of urine), and erection.
Sympathetic influence - Sympathetic Nervous System (SNS) is always active at a basal level and becomes more active during times of stress. Its actions during the stress response comprise the fight-or-flight response. Activates when scared- quiz right now!!
Catecholamine (NE/E) Norepinepherine is the neurotransmitter
Results in tachycardia ( increased heart rate)
Parasympathetic influence- works in a Complimentary way to sympathetic
Acetylcholine (this system only uses acetylcholine (ACh) as its neurotransmitter)
Results in bradycardia (slows heart rate)
Cortical  anticipatory  heart rates before 12 min run!!
Mild acttion sympathetic NS
Sympathetic nervous system
Promotes a "fight or flight" response, corresponds with arousal and energy generation, inhibits digestion:
Diverts blood flow away from the gastro-intestinal (GI) tract and skin via vasoconstriction.
Blood flow to skeletal muscles, the lung is not only maintained, but enhanced (by as much as 1200%, in the case of skeletal muscles).
Dilates bronchioles of the lung, which allows for greater alveolar oxygen exchange.
Increases heart rate and the contractility of cardiac cells (myocytes), thereby providing a mechanism for the enhanced blood flow to skeletal muscles.
Dilates pupils and relaxes the lens, allowing more light to enter the eye.
[edit] Parasympathetic nervous system
Promotes a "rest and digest" response; promotes calming of the nerves return to regular function, and enhances digestion.
Dilates blood vessels leading to the GI tract, increasing blood flow. This is important following the consumption of food, due to the greater metabolic demands placed on the body by the gut.
The parasympathetic nervous system can also constrict the bronchiolar diameter when the need for oxygen has diminished.
During accommodation, the parasympathetic nervous system causes constriction of the pupil and lens.
The parasympathetic nervous system stimulates salivary gland secretion, and accelerates peristalsis, so, in keeping with the rest and digest functions, appropriate PNS activity mediates digestion of food and indirectly, the absorption of nutrients.
Is also involved in erection of genitals, via the pelvic splanchnic nerves 2–4.

15. CV system during exercise
Acute Adaptations
Chronic adaptations
Q: You have a set amount of blood in your system. What are the 2 ways that your body could send more blood around when you are exercising? Increase HR and Increase amt pumped with each beat (SV)

16. Heart rate At rest- 60-80 bpm Pre exercise- anticipatory response
Trained athletes  lower (28-40 bpm)
Pre exercise- anticipatory response
Sympathetic nervous system release N/E and ephedrine
Increases during exercise to steady state

17. Cardiovascular Dynamics
Q = HR × SV (Fick Equation)
Q: cardiac output
HR: heart rate
SV: stroke volume
Excellent section text starts on page 352

18. Cardiac Output At Rest During Exercise Q = 5 L p/Min
Trained RHR = 50 bpm, SV = 71
Untrained RHR = 70 bpm, SV = 100
During Exercise
Untrained- Q = mL p/min, MHR = 195
SV av 113 ml blood p/beat
Trained- Q= ml p/min, MHR = 195
SV av 179 ml blood p/beat
Q = HR × SV
At rest Q = same for trained/ untrained. RHR is lower for trained, therefore Sv is higher
Reasons = heart muscle stronger- increased ventricular volume; and able to eject a greater volume with more power
Slower HR allows Increased time for blood to fill up.
During exercise blood flow increases in direct proportion to exercise intensity
Training increases cardiac output – able to pump more per beat
What do you get it you have higher cardiac output??? MORE OXYGEN!!! And MORE BLOOD GLUCOSE, as well as Better DISSIPATION OF LACTATE

19. Increases in Stroke Volume
Increases in response to exercise
Is ability to fill ventricles, particularly left ventricle
And more forceful contraction to pump blood out
Training adaptations
left ventricle hypertrophy
Increased blood volume
Reduced resistance to blood flow
Increased ability to fill ventricles during diastole, or when heart is relaxed, lood is more efficiently able to come on in
More forceful contraction to pump blood out- Systolic contraction increases in force. Governed by neurohormonal influence
Training adaptations

20. Training Adaptations: Heart
Eccentric hypertrophy
Slight thickening in left
ventricle walls
Increases left ventricular
cavity size
Therefore increases stroke
volume
LV is the one that pumps all of the blood out into the body

21. Cardiac output distribution
At rest
¼  liver; 1/5  kidney 7 muscles
During exercise
Varies according to many conditions, but essentially, for intense exerciseall blood is shunted to the muscles and away from other tissues

22. Oxygen transport When arterial blood is saturated with oxygen :
1 litre blood carries 200 ml oxygen
During exercise
Q = 22L p /min
= 4.4L oxygen per minute
At rest
Q = 5L p/ min
= 1 L oxygen per minute
250 ml required at rest
Remainder- oxygen reserves
Increase in cardiac output directly increases their Vo2 max  as we can see, the concentration of oxygen in the blood remains the same, so only option to increase vo2 max is to increase cardiac output
How to we increase cardiac output? Increase HR/SV. If we assume that their HR is at max, not able to change that. Therefore the change comes from the increase in stroke volume

23. Stroke Volume and Cardiac Output
Exercise  increases stroke volume during rest and exercise
Slight decrease heart rate
Increase in cardiac output comes from increased stroke volume
Decrease in HR not enough to counteract effects of increased SV

24. Heart Rate
Elite athletes have a lower heart rate relative to training intensity than sedentary people

25. Saltin, 1969 Endurance athletes
Increase in Stroke volume and decrease in heart rate due to 55 day training program
Essentially intensity along x axis
Endurance athletes
Sedentary college BEFORE 55 day aerobic training program
Sedentary college AFTER

26. 4 training sessions can increase plasma volume by 20%
Total Blood Volume
* Plasma volume
4 training sessions can increase plasma volume by 20%
*Increased RBC
- Number of RBC increases, but due to increase in Plasma volume, concentration stays the same
Blood plasma is the liquid component of blood, in which the blood cells are suspended. Plasma is a yellow colored liquid. Plasma is the largest single component of blood, making up about 55% of total blood volume.
Carry more RBC  more haemoglobin
Increased RBC
These things start a whole chain of events that leads to further training adaptations

27. Blood Pressure
Aerobic exercise reduces systolic and diastolic BP at rest and during exercise
Particularly systolic
Caused by decrease in catecholamines
Another reason for exercise to be prescribed for those with hypertension
Resistance training not recommended due to acute high BP it causes
Particularly systolic- what is systolic? Why would exercise reduce this?
Catecholamines- sympathetic nervous system hormones

28. Oxygen Extraction
Training increases quantity of O2 that can be extracted during exercise
Not only are you getting a greater amount of blood per minute, but you are getting a higher concentration of oxygen
How would you therefore explain increased Vo2 Max in 2 people ?

29. Chronic Adaptations to Exercise- Chapter 10
Cardiovascular adaptations to training are extremely important for improving endurance exercise performance, and preventing cardiovascular diseases.
The more important of these adaptations are,
 Size of heart  ventricular volumes
 total blood volume
-  plasma volume
-  red cell mass
 systolic and diastolic blood pressures
 maximal stroke volume
 maximal cardiac output
 extraction of oxygen

30. Factors Affecting Chronic adaptations
Initial CV fitness
Training:
Frequency- 3 x p/week
Only slightly higher gains for 4 or 5 times p/week
Intensity
Most critical
Minimum is 130/ 140 bpm = (av) 50-55% Vo2 max/ 70% HR max
Higher = better
Time
Or duration- 30 min is minimum
Type
Specificity
In terms of vo2 max
initial- some have higher due to genetics etc
Freq. – slight gains in vo2 max that come from training those extra 2 days are not worth the potential injury
Intensity
Time- does 2 x 15min = 30 min?? Research inconclusive, varies for each type of activity
Improvements within a few weeks
Continues on in chapter 13

31. Pulmonary System

33. Pulmonary Structure and Function
The ventilatory system
Supplies oxygen required in metabolism
Eliminates carbon dioxide produced in metabolism
Regulates hydrogen ion concentration [H+] to maintain acid-base balance
3 main functions
GAS EXCHANGE ANIMATION

34. Breathing
At rest
Air in  Trachea- humidified and brought to body temperature
 divides into 2 branches lungs
Lungs hold 4-6 litres of ambient air- huge surface area
300 million alveoli
250 ml oxygen in and 200 ml Carbon dioxide out each minute
Main idea of the lungs is that they are a very compact and convenient area for gas exchange
Probably read in the text that, although lungs weigh only about 1 kg, if spread out, would cover the same area as ½ a tennis court, or 1 whole badminton court
Alveoli
Where all the action happens!! Latin for “little cavity”
Alveoli is completely intertwined with capillaries; and the walls of the alveoli and the cappilaries are both thin enough to allow oxygen and carbon dioxide to travel through the walls

35. Diaphragm contracts (flattens) Moves downward (10cm) Thoracic volume
Inspiration
Ribs rise
Diaphragm contracts (flattens)
Moves downward (10cm)
Thoracic volume
Air in lungs expands
Pressure
to 5 mm Hg below atmospheric pressure
Difference between outside air and lungs = air is sucked in until pressure inside and out is the same
Lungs do not contain muscle that contracts them (Like the heart)
Instead, diaphragm controls thoracic volume and subsequent pressure.
Ribs rise due to contraction of intercostal muscles

36. Expiration Ribs move back down Diaphragm relaxes (rises)
Thoracic volume
Pressure
Difference between outside air and lungs = air is pushed out until pressure inside and out is the same
Ribs move down due to relaxation intercostal muscles (breathing at rest)
Feel that pressure increase when you are swimming underwater, holding breath
Expiration during exercise is far more forceful due to the actions of the intercostal and abdominal muscles  more forceful expiration to eliminate Co2  also increased differences in pressure that results in increased oxygen being drawn in.
What do you notice about the arrows on both of these pages??
Up down up down or down up down up
Can simplify and say that when diaphragm goes down, air goes in and when diapraghm goes up, air goes out

38. Pulmonary system during exercise

39. Lung Volumes Static lung volume tests Dynamic lung volume tests
Evaluate the dimensional component for air movement within the pulmonary tract, and impose no time limitation on the subject
Dynamic lung volume tests
Evaluate the power component of pulmonary performance during different phases of the ventilatory excursion
Static= space available
Dynamic = power / force behind expiration

40. Spirometry
Static and Dynamic lung volumes are measured using a spirometer

41. Static Lung Volumes Page 146 of text
TV- breath normally- this is your tidal volume
IRV- breath normally, breath out normally, then breath in as much as you can. This is inspiratory reserve- it is the max capacity for air in the lungs. Can be 2-3 litres
Breath normally
ERV- Breath in normally, then breath out as much as you can – average one litre of air
FVC (Forced vital capacity) = maximum you can force in and out of lungs IRV + ERV
RLV- residual- the lungs are never empty- RLV is the amount left in them after forced expiration. Usually one litre\
TLC- Total lung capacity = amount you can force in/ out + residual volume left- TLC = IRV + ERV + RLV

42. Dynamic lung volumes Depend on Volume of air moved and the
Speed of air movement
FEV/FVC ratio
MVV
Remember dynamic is looking at the power behind what you can breath

43. FEV/FVC Ratio Forced Expiratory Volume Forced Vital Capacity
Ratio tells us the speed at which air can be forced out of lungs
Normal = 85% FVC can be expired in 1 second.
FVC= max amount expired after maximal inspiration
Ususally used in the diagnosis of obstructive lung diseases such as emphysema, asthma etc

44. Maximal Voluntary Ventilation
Breath as hard and fast as you can for 15 seconds
Multiply by 4
And you have Maximal Voluntary Ventilation
MVV-
Males: Litres
Females: Litres
Elite athletes up to 240 Litres

45. Minute Ventilation At Rest 12 breaths per minute
Tidal volume = 0.5L per breath
= 6 Litres of air breathed p/min
During Exercise
50 breaths p/ minute
Tidal Volume = 2 L per breath
= 100L p/min

46. Alveolar Ventilation Minute ventilation is just total amount of air
Alveolar ventilation refers to the portion of minute ventilation that mixes with the air in the alveolar chambers
Minute ventilation minus anatomical dead space ( ml)- the air that is in the trachea, bronchi etc
Anatomical dead space = air that isn’t in alveoli and is therefore no good at all as is not involved with gas exchange in the blood

47. Alveolar Ventilation =
Minute ventilation (TV x breathing rate) – dead space

48. Gas exchange

49. Gas Exchange in the Body
The exchange of gases between the lungs and blood, and their movement at the tissue level, takes place passively by diffusion

50. Page 149 of text

51. Oxygen Transport in the Blood
Combined with hemoglobin — In loose combination with the iron-protein hemoglobin molecule in the red blood cell
Each Red Blood Cell contains 250 million hemoglobin molecules
Each one can bind 4 oxygen molecules

52. CO2 Transport in Blood In physical solution As carbamino compounds
(~7%) dissolved in the fluid portion of the blood
As carbamino compounds
(~20%) in loose combination with amino acid molecules of blood proteins
As bicarbonate
(~73%) combines with water to form carbonic acid

53. Regulation of Pulmonary Ventilation
Temp- increse in body temp directly stimulates neurons to fire to tell the diaphragm and intercostal muscles to act

54. Regulation at rest: Plasma Pco2 and H+ Concentration
The partial pressure of CO2 provides the most potent respiratory stimulus at rest
[H+] in the cerebrospinal fluid bathing the central chemoreceptors provides a secondary stimulus driving inspiration
If you hold your breath, the thing that forces you to breath again is the high Co2

55. Ventilatory Regulation During Exercise
Chemical control
Po2
Pco2
[H+]
Nonchemical control
Neurogenic factors
Cortical influence
Peripheral influence
During exercise
Remember oxygen debt and deficit?
Start exercise- rapid increase in breaathing rate- 1st 20 seconds = plateau
Stop exercise- fairly rapid slowing down, but remains at 40% of what was happening during exercise
Think about what happened in lactate threshold test
Chemical- levels of these three prompt action Co2 is by product of atp production; Hydrogen is produced in glycolysis  Kreb’s cycle
Nonchemical-
Neural control- brain tells the neurons to tell the diaphragm and intercostals to relax/ contract  inflate
Cortical- anticipatory effect
Peripheral- respiration increases because the joints/muscles are moving  receptors

56. Ventilation in steady rate exercise
Of oxygen ( V E/ V O2)
Quantity of air breathed per amount of oxygen consumed
Remains relatively constant during steady-rate exercise- 25 L air breathed per 1L o2 consumed at 55% Vo2 max
Of carbon dioxide ( V E/ V CO2)
Remains relatively constant during steady-rate exercise

57. Ventilatory Threshold
The point at which pulmonary ventilation increases disproportionately with oxygen uptake during graded exercise
The excess ventilation relates to the increased CO2 production associated with buffering of lactic acid
Have to increase ventilation to increase amount of oxygen to enable aerobic respiration

58. Pulmonary adaptations to Exercise

59. Goals of aerobic training

60. Adaptations to Maximal exercise Minute ventilation increases
Increased oxygen uptake
Pulmonary adaptations often some of the first to be noticed basically reduced feeling of breathlessness in untrained
20 weeks of training increased pulmonary muscle strength by 16%  intercostals and diaphragm better able to create pressure differences which result in inspiration/ expiration

61. Submaximal Exercise Ventilatory equivalent for oxygen
Ventilatory muscles stronger
Ventilatory equivalent for oxygen
( V E/ V O2) reduces indicates breathing efficiency
This leads to
Reduced fatigue in ventilatory muscles
O2 that would have been used by those muscles can be used by skeletal muscle.
Ventlatory equivalent for oxygen is the ratio of the amount of air breathed to the amount of oxygen obtained

62. Pulmonary Adaptations
Increased tidal volume
Decreased breathing frequency
Increased time between breaths (Increased time for oxygen to get into bloodstream)
Therefore less oxygen in exhaled air

63. Summary Need to know Cardiac and pulmonary Structure and Function
Veins/arteries/cappilaries
Flow of blood through the heart
Alveoli bronchii etc
Flow of inspired air and pulmonary exchange
Acute adaptations to exercise
Chronic adaptations to exercise