PE 254

Chapter 12©2008 McGraw-Hill Companies.

All Rights Reserved. 2

Heart, blood vessels, hormones, enzymes and wastes.

Four chambers (size of a fist).◦ Upper chambers (Atriums).

Right atrium contains the sinus node◦ Lower chambers (Ventricles).◦ Vena cava.◦ Pulmonary Artery and vein.◦ Aorta.◦ Coronary Arteries and veins.◦ Veins◦ Capillaries

Chapter 12©2008 McGraw-Hill Companies.

All Rights Reserved. 4

Chapter 12©2008 McGraw-Hill Companies.

All Rights Reserved. 6

Blood vessels◦ Arteries = vessels that carry blood away from

the heart◦ Veins = vessels that carry blood to the heart◦ Capillaries = very small blood vessels that

distribute blood to all parts of the body

Endothelium (inner and outer lining)

Elastic tissues◦ Rebounds◦ Evens flow

Smooth muscles Fibrous tissue

◦ Tough◦ Resists stretch

Figure 15-2: Blood vessels

Alveoli = tiny air sacs in the lungs through whose walls gases such as oxygen and carbon dioxide diffuse in and out of the blood

Lungs expand and contract about 12–20 times a minute at rest

The electrocardiogram (ECG) is an indirect measure of the electrical activity of the heart. The activity can be measured by placing leads on the surface of the skin. The ECG is made up of five points P, Q, R, S and T. The points are grouped together to represent important electrical events in the heart. A normal healthy heart’s ECG is represented by 3 distinct waves: •The P wave, •The QRS complex and •The T wave.

The P wave represents atrial depolarization followed by atrial contraction. The QRS complex represents ventricular depolarization followed by ventricular ejection. The T wave represents ventricular repolarization. Other than the three mentioned above there are other significant pieces to the ECG: The PR segment is the AV nodal delay. The ST segment is the time it takes for the ventricles to contract and empty. The TP interval is the time during which the ventricles are relaxing and filling. http://sprojects.mmi.mcgill.ca/cardiophysio/EKGpwave.htm

http://www.sh.lsuhsc.edu/fammed/OutpatientManual/BasicECG.htm

Carotid artery in the neck Radial artery in the wrist

Count beats for 10 seconds and multiply the result by 6 to get rate in beats per minute

Place the bell of the stethoscope over the third intercostals space (i.e., the space between two adjoining ribs) to the left of the sternum (breast bone). (Or to the left of the sternum just above the nipple line).

Client should rest 5 to 10 minutes in either a supine or seated position before measuring resting heart rate.

Or, client should take resting heart rate first thing in the morning. This method is the most accurate.

AT REST Heart rate: 50–90

beats/minute Breathing rate: 12–20

breaths/minute Blood pressure: 110/70 Cardiac output: 5

quarts/minute Blood distributed to

muscles: 15–20%

DURING EXERCISE Heart rate: 170–210

beats/minute Breathing rate: 40–60

breaths/minute Blood pressure: 175/65 Cardiac output: 20

quarts/minute Blood distributed to

muscles: 85–90%

Figure 25-7: Distribution of cardiac output at rest and during exercise

Effect of exercise on Cardiac Output

Cardiac output is the volume of blood pumped out of each ventricle per minute

It must be remembered that the cardiac output is the amount of blood pumped by EACH ventricle, and NOT the total amount pumped by both ventricles

Two factors determine the magnitude of the cardiac output; these are the stroke volumeand the heart rate

Cardiac Output = Stroke Volume x Heart Rate

Stroke volume is the volume of blood ejected from EACH ventricle per beat

Heart rate is the number of times the heart beats in one minute; that is the number ofcardiac cycles per minute

EXAMPLE: If the heart is beating at a rate of 75 beats per minute, and the volume ofblood ejected from EACH ventricle, for each beat, is 70 cm3 then:

CARDIAC OUTPUT = 75 x 70, which is 5250 cm3 or 5.25 dm3 per minute

Spiroergometric

Spiroergometry is a diagnostic analysis in order to rate the physical condition and fitness. The analysis is based on a step-by-step plan including bicycle ergometer or treadmill fitness tests. With the help of a special mask certain parameters can be measured - for example oxygen and carbon dioxide values, respiratory rates, respiratory volumes, heart rates, etc. You receive detailed information on the following topics:  Which pulse rate is ideal for activating the body's fat burning process? How can I lose weight in the long term with tailor-made workout? Is my resting respiratory rate or my breathing under exertion economic or not? What about the efficiency of my cardiovascular system?  Spiroergometry is equally suitable for amateur sportsmen, pros and health-conscious sportsmen of all ages.

 

Target heart rate zone◦ Estimate your maximum heart rate (MHR)

220 – your age = MHR

◦ Multiply your MHR by 65% and 90% People who are unfit should start at 55% of MHR

◦ Example: 19-year-old MHR = 220 – 19 = 201 65% training intensity = 0.65 X 201 = 131 bpm 90% training intensity = 0.90 X 201 = 181 bpm

A subject’s pre-exercise heart rate is 65 beat per minute (bpm). After a 15-minute bout of cardiorespiratory exercise, the subject’s post-exercise heart rate is 173 bpm. The subject is 26 years of age. Find the following:

 The subject’s maximum targeted heart rate for

cardiorespiratory training intensity?  220 – 26 = 194

The subject’s percentage of cardiorespiratory training intensity?

173/194 = 89%

Figure 15-4: Elastic recoil in the arteries

"Blood pressure"◦ Systolic over diastolic◦ About 120/80 mmHg

Sphygmomanometer◦ "Estimate of pressure"◦ Korotkoff sounds

Figure 15-7: Measurement of arterial blood pressure

Use appropriately size cuffs. The bladder in the cuff should cover two thirds the arm circumference to avoid false measurements.

Size Arm Girth Bladder dimensions: Child 13-20 cm 8 x 13 cm Adult 24-32 cm 13 x 24 cm Large 32-42 cm 17 x 32 cm

ACSM (2001), ACSM's Resource Manual for Guidelines for Exercise Testing and Prescription, 4th ed., pg 7.

YMCA of the USA (2000), YMCA Fitness Testing and Assessment Manual, 4th Edition.

Blood volume Cardiac output Resistance Distribution

Figure 15-10: Factors that influence mean arterial pressure

http://blood-pressure.emedtv.com/high-blood-pressure-video/introduction-to-high-blood-pressure.html

http://www.youtube.com/watch?v=u6saTO8_o2g

http://www.youtube.com/watch?v=ElCbQMiBC6A