Exercise

Introduction

People are designed to be active. It is abnormal to be sedentary. Immobility can seriously damage your health.

Effects of immobility on healthy subjects

Deconditioning - loss of functional capacity secondary to lack of use

* Decreased metabolic rate

* Decreased blood volume and red cell mass

* Increased urinary secretion of calcium, phosphorus and nitrogenous waste products

* Decreased muscle mass

* Increased pulse rate

* Inability to tolerate positional change

Hazards of immobility on the body systems

1. Cardiovascular system

Deep vein thrombosis, (DVT)

Pulmonary embolism, (PE)

Postural hypotension

Increased cardiac workload

2. Respiratory system

Hypostatic pneumonia

3. Muscular skeletal system

Osteoporosis

Muscle wasting and joint stiffness

4. Urinary system

Calculi

Retention

Incontinence

Infection

5. Gastrointestinal system

Constipation

6. Metabolic changes

7. Psychological/psychiatric

8. Pressure sores

Reduced integrity of the integument

9. Individual self - care deficits

Physiological requirements for exercise

Oxygen

Metabolic substrate

Removal of waste

Adequate arterial supply

Adequate venous drainage

Neuronal control

Correct environment for enzymic activity

Acute effects on the body

Increased heart rate and volume

Increased respiratory rate and volume

Increased blood pressure

Increased heat production

Types of exercise

Aerobic exercise

Anaerobic exercise

Lactic acid

Maximal

Sub-maximal

Isometric - no muscle movement

Isotonic - muscles contract and cause movement

An exercise programme

Fitness takes time

Gradual build up over months

Life style - not bursts

Each individual should be individually assessed

Medical advise if in any doubt

Never exercise with any form of systemic infection

20 - 30 minutes five or more times per day - to benefit the cardiovascular system

LSD

Build up fast muscle fibres

Build up slow muscle fibres

Pay attention to diet

Long term effects of exercise

Factor Effect

Mortality from ischaemic heart disease

Number of coronary capillaries

Maximum cardiac output

Resting heart rate

Number of muscle capillaries

Size and tone of muscle cells

Levels of HDL cholesterol

Bone mass

Number of mitochondria

Uptake of oxygen from capillaries to tissues

Blood flow and strength of joints

Endorphine secretion to make you feel good

Effects of inflammation and trauma on joints

From Chris

DIPLOMA IN HIGHER EDUCATION - COMMON FOUNDATION PROGRAMME - PHYSIOLOGY MODULE - NUR 105

SESSION - 1 Cardio-vascular System. D.1.

Introduction to the cardiovascular system in relation to exercise.

CARDIO VASCULAR SYSTEM

D.1 Introduction

D.1.1 Explain the structure of the heart

D.1.2 Explain the coronary and systemic circulation

D.1.3 Appreciate an overview of the interaction of the systems, (eg respiratory, musculo-skeletal and cardiovascular) with particular reference to exercise.

D.1.4 Observe the effects of exercise on respiratory and heart rates

Followed by a guided study on the cardio-vascular system

Session 1

Introduction to the physiology - brief overview and tree of knowledge

Objectives for this session O.H.P.

What does the cardiovascular system consist of?

The heart and blood vessels which are the arteries, veins and capillaries. The blood and its components are integral to the system.

What is the function of the cardiovascular system?

Transport of carbon dioxide and oxygen, nutrients i.e. food substances, water, ions, hormones, metabolic products, defence cells.

What does the heart do?

Acts as a pump.

Hollow muscular organ

Weight 250 - 300 grms (9-12 oz)

Beats 70 per min - 100,000 times a day.

Where is the heart located? O.H.P.

Thoracic cavity, between the lungs in the mediasteinum. TORSO & MODELS

D.1.1 Explain the structure of the heart O.H.P.

The heart is a 4 chambered muscular pump

Considered a double pump because the left side does not have any direct communication with the right side (following birth).

The chambers are divided into two atria and two ventricles

The septum is the dividing wall centrally and valves divide the upper and lower chambers and the exits to the main arteries leaving the heart.

The two atria contract simultaneously and force blood downwards into the ventricles, they then relax and the two ventricles contract together.

Blood flow through the heart - use diagram to explain O.H.P.

Explain coronary , systemic and pulmonary circulation O.H.P

Where does the heart wall get its blood supply?

The heart wall receives its blood supply from the right and left coronary arteries which originate from the ascending aorta.

Layers of the heart

What are the 3 layers of the heart?

The endocardium is the inner layer which is thin and lines the inside of the myocardium and covers the valves of the heart and the tendons are attached to the valves.

The Myocardium - middle layer is the cardiac muscle tissue and constitutes the bulk of the heart, it is responsible for the contraction of the heart.

The Epicardium - outer layer, its thin, transparent layer composed of serous tissue and mesothelium.

The pericardium - The heart is enclosed and held in place by the pericardium, which keeps the heart in position but allows sufficient freedom of movement when it is working fast and hard. The pericardium is composed of an outer fibrous layer and an inner serous pericardium. The serous pericardium is composed of a parietal and visceral layer. Between the layers of the serous pericardium is a potential space filled with pericardial fluid that prevents friction between the two membranes.

What controls heart rate?

The demand for oxygen, nervous system, endocrine system e.g. adrenalin (norepinephrin).

Brief explanation of control of heart rate.

Effects of exercise - general and on the cardiovascular system

The interaction of the systems

Effects of exercise on respiratory and heart rate.

The effects of exercise on the body and cardio-vascular system can be considered in 2 ways

1. The changes that result during the actual exercise period itself

2. The longer term consequences of undertaking regular exercise

Encouraging people to be active and do more exercise forms an important health promotion message.

In a broad sense, physical performance or fitness (the capacity to do physical work) is determined by the individual's capacity for energy output (mainly determined by the cardiovascular and respiratory systems), neuromuscular function, joint mobility and psychological factors, such as motivation. When exercising the body needs to maintain the chemical and physical equilibrium of the cells.

During exercise there is a need to increase the delivery of oxygen and nutrients to the active muscle tissue (this can increase to 50 times in an elite athlete) and to also increase the rate of removal of heat, carbon dioxide, water and metabolic waste products. This necessitates a large increase in the exchange of materials between the intra- and extracellular fluids. In order to prevent the metabolism in the active cells becoming anaerobic (i.e. without oxygen) there needs to be an increase in cardiac output.

What happens when we exercise?

The 'mental' anticipation of exercise can result in sympathetic arousal and lead to an increase in heart rate. Once the exercise is underway, the muscles that are active require an increased blood flow to provide necessary oxygen and nutrients and to remove waste products. Blood flow to the kidneys and gut is reduced as a compensatory vasoconstriction occurs, although blood flow to the skin may increase in order that the body can lose heat. In order for the blood flow to the muscles to increase, the cardiac output must also increase, and this is partly brought about by sympathetic activity.

The maximum attainable heart rate varies with sex, age and state of physical fitness. As a guide, the maximum attainable heart rate is given by the formula 220 - age in years. The cardiac output increases from the resting value of approximately 5 litres per minute and can reach 25 litres per minute ( or even 35 l.min in elite athletes). The ability of the cardiovascular system to cope with exercise increases considerably with training. Athletes have a slower heart rate at rest, resting heart rates of 40 are not uncommon in very fit people.

The benefits of regular physical aerobic exercise

Improved cardiovascular function (reduced heart rate at given oxygen consumption; improved efficiency of heart muscle; lower blood pressure)

Inhibition of clotting processes and platlet aggregation

Favourable trend in incidences of cardiac morbidity and mortality

Increased metabolic rate - both during and after exercise

Can reduce obesity due to increased metabolic turnover

Favourable increase in ratio of serum high density lipoproteins to low density lipoproteins

Enhanced tolerance to hot environments.

Muscle size and strength improve, plus ligament strength (e.g. helps with posture, protects from joint instability and injury, and back pain in pregnancy)

Can help prevent osteoporosis

Increased capillary density in skeletal muscle

Reduced perceived exertion at given work rate

Can help to maintain normal blood glucose levels, especially in diabetics

Increased rate of endorphin secretion (linked to feelings of well-being, reduced anxiety and stress and antidepressant effects).

Ref Page 445 - Hinchliff, S.M. et al. (1996). Physiology for Nursing Practice (2nd Ed). London. Bailliere Tindall.

Long- term effects of inactivity or regular exercise.

Physical activity at its most strenuous is an enormous challenge to body systems. Maximum performance depends both on optimum function of many different parts of the body and on optimum environmental conditions. Fitness can be developed by a planned programme of activity that needs to be kept up if the improvement in condition is not to be lost. If you experience a prolonged period of inactivity, loss of strength and fitness in inevitable.

The form of exercise practised determines the nature of the changes that occur both in the muscles an in the body as a whole. Very short bursts of intense activity are good at developing muscle strength, but they do relatively little for the heart and circulation. Longer periods of regular sub-maximal exercise are required to improve the function of these.

Type of exercise Effect

Bursts of intense activity (seconds) ^ Muscle strength

Intense activity (1 min) ^ Anaerobic power

repeated after a few minutes' rest

Less than maximal activity for 3 - 5 min with ^ Aerobic power

intervening similar periods of rest

Sub-maximal exercise for 30 min ^ Endurance

Rutishauser. S. (1994) Physiology and Anatomy - A basis for Nursing and Health Care. Churchill Livingstone. London.

OBSERVING PULSE RATE, RHYTHM, FORCE, QUALITY

OBSERVING RESPIRATORY RATE, DEPTH AND RHYTHM

WHY IS THE RESPIRATORY AND PULSE RATE MEASURED?

1. to establish a baseline

2. to monitor fluctuations in respirations or changes in the pulse.

The pulse is a rhythmic throbbing caused by regular expansion and contraction of an artery as blood is forced into it by the contraction of the left ventricle.

Normal in adult 70 beats per minute.

OBSERVE

RATE - slightly faster in women - rapid in infants, mild increase in old age

Tachycardia - pain, anger, fear, exercise fever, anaemia, hypoxia, shock, CCF.

RHYTHM - Should be regular. Sinus arrhythmia - increases at the peak of inspiration and decreases on expiration, common in children and young adults

FORCE - Pulse pressure is difference between systolic and diastolic pressure

QUALITY - bounding, normal, weak-thready, absent

Elasticity. The flexibility of the artery feels different. Supple in young adult, hard in arteriosclerosis

1. Explain procedure

2. Ensure comfort and required position

3. Palpate peripheral artery (radial)

4. 2nd or 3rd finger tips

5. Count for 60 seconds to detect abnormalities.

WHAT ARE WE LOOKING FOR WHEN EVALUATING RESPIRATION/

QUALITY - RATE - DEPTH - PATTERN

QUALITY normal relaxed breathing is effortless, automatic, regular and almost silent

RATE and depth determine the type of respiration. The normal rate is 12 - 18 breaths per minute in adults, it is faster in infants and children

ratio of pulse to respiration 5:1

DEPTH is the volume of air moving in and out with each respiration. The tidal volume is normally about 500 ml in an adult and should be constant with each breath. a spirometer is used to measure the precise amount

PATTERN Tachypnoea - increase, seen in fever, resps increase approximately 7 for every 1 degree centigrade

Pneumonia, COAD, lesions of pons or brain stem

BRADYPNOEA - decreased - depression of respiratory centre eg narcotics, tumours

HOW TO MEASURE

1. Attempt to count the respirations when the patient is at rest, not explaining to patient, WHY?

2. Patient comfortable

3. Observe the movement of chest wall

4. Evaluate sounds made

5. Count for sixty seconds, one inhalation and one exhalation together count as one respiration

6. Record number

Usually measure pulse, then unobtrusively count respirations

Breathing is probably the only AL which individuals perform independently from birth to old age.

VIDEO ON THE CARDIOVASCULAR SYSTEM

In pairs take pulse and respiration then exercise for a few minutes then take pulse and respiration. Write down and correlate the results before and after, are they in the ration 5:1.

The guided study of the cardiovascular session covers the anatomy and physiology in more detail in preparation for the sessions on the CVS later on.

THE CARDIOVASCULAR SYSTEM - DIRECTED STUDY

The overall aim of this directed study is to allow you to reflect upon and develop your existing knowledge concerning the cardiovascular system.

You are required to insert the correct word(s) or phrases into the appropriate spaces (the number of words or letters in the words are given in brackets), and to draw or label simple diagrams related to the cardiovascular system.

The text used to prepare this directed study is that of Ross and Wilson - Anatomy and Physiology. You may of course use other texts if you so wish.

THE CARDIOVASCULAR SYSTEM

The heart is located in the (8) cavity in the middle mediastinum between the lungs. It lies a little more to the left than the right.

STRUCTURE OF THE HEART

The heart is composed of (5) layers of tissue. These are:-

(i) (11) (made up of two sacs)

(ii) (10)

(iii) (11)

Layer (ii) is composed of specialised (2 words 7 & 6) tissue found only in the heart.

The heart is divided into right and left sides, separated by a partition called

the (6).

Each side is divided into an upper chamber, the (6) and a lower chamber, the (9).

There are valves between the atria and the ventricles, which open and close when the pressure in the chambers change.

Draw and label a simple diagram of the heart.

BLOOD FLOW THROUGH THE HEART

Draw and label a simple diagram of the blood flow through the heart.

Summarise the blood flow through the heart by completing the following sentences:-

The right side of the heart deals with (12) blood.

The left side of the heart deals with (10) blood.

The vessels carrying blood to the heart are (5).

The vessels carrying blood away from the heart are (8).

Other blood vessels that are concerned with the circulatory system are:-

(i) (10)

(ii) (7)

(iii) (11)

CONDUCTION SYSTEMS OF THE HEART

There are small groups of specialised cells in the (10) layer which initiates and conduct impulses of contraction over the heart muscle.

These impulses originate in the (2 words, 10 & 4). This is often referred to as the " " (Hyphenated words 4 & 5) of the heart.

Impulses are then passed to the (2 words 16 & 4), the (3 words, 6, 2, 3), down the left and right (2 words, 6 & 8),

and into a network of (2 words, 8 & 6)

Draw and label a simple diagram of the conduction system of the heart.

The pattern of electrical activity produced by the heart may be displayed on a screen or traced on paper. This tracing is referred to as an (17).

The normal tracing shows five waves.

These are:-

(i) (1) wave

(ii) (1) wave

(iii) (1) wave

(iv) (1) wave

(v) (1) wave

Draw and label a diagram of the tracing of one cardiac cycle.

Wave (i) represents (6) contractions

Waves (ii) (iii) (iv) represents (11) contractions