Specialist PSI Exercise Module CARDIOVASCULAR SYSTEM Main transport system –Gases –Food –Waste –Hormones –Minerals –Medications Heart rate - controlled

Specialist PSI Exercise Module

CARDIOVASCULAR SYSTEM

• Main transport system – Gases– Food– Waste– Hormones– Minerals– Medications

• Heart rate - controlled by autonomic nervous system


• Circulation

–Pulmonary (to lungs)

–Systemic (to body)

–Coronary (to heart muscle)

• Blood vessels -

“tubes”

–Arteries - from heart to body

–Veins - from the body to the heart

–Capillaries - interchange of gases, food and waste


CONTRACTION OF HEART MUSCLE

• Heart muscle contracts automatically – spontaneous discharge of pacemaker cells

• Sino-atrial node - heart’s pacemaker located in right atrium. Impulses travel through atria to ventricles via A-V node.

• Heart muscle cells are connected


CONTRACTION OF HEART

• Parasympathetic activity slows the heart

• vagus nerve releases Acetylcholine

• Sympathetic activity quickens the heart

• release of Adrenaline and neurotransmitters

• Blood Pressure• cardiac output flowing into vascular system influences systolic pressure • resistance of blood vessels influences diastolic blood pressure


VOLUMES

• Stroke Volume

• Blood per beat

• Cardiac Output

• Blood per minute

• Maximal O2 Uptake

• Amount of oxygen that can be used in one minute – ml/kg/min


Age

% VO2 max

Maxim

al O

xyg

en

Up

take (m

l/kg

.min

)

Dressing

Making the bed

Walking (3mph)

Stair Climbing (slowly)

50

75

25

0

75

50

25

20

40

030 80

% VO2 max

100

100

Men


EFFECTS OF AGEING

At rest no major changes to heart rate, stroke volume or cardiac output due to age alone BUT when the system is challenged then there are age-related deficits – compounded by sedentary behaviour

• stiffness of heart wall (collagen)

• Maximal H.R.

• Maximal stroke volume

• Maximal cardiac output

• Maximal aerobic power – 10% per decade

• systolic blood pressure

• incidence of postural hypotension (failure of venous return)


Fallers vs Non-fallers

• Cardiac symptoms can affect falls– Syncope– Arrythmias– TIAs– Postural Hypotension

• Cardiac medications not a major risk except in combination with other medications (>4)


FUNCTIONAL CONSEQUENCES

• Tasks will require % of maximum in older person

• Unable to sustain submaximal activities

• Postural hypotension can lead to blackout / drop

attack / injury

• Fartlek training approach

• Circulation re-booster on major postural

transitions


EFFECTS OF TRAINING

• Increased time in Diastole ( heart health)

• Maximal aerobic power can be by

– Muscle oxidative enzymes

– Muscle capillarisation

– Stroke volume and cardiac output

• Relative increases similar to young people

• Everyday tasks require % of VO2 max

• Everyday tasks can be performed for longer with greater

ease

Hypertension and Postural Hypotension in some


PULMONARY SYSTEM

• Main transport system for gases

– Oxygen

– Carbon Dioxide

• Ventilation controlled by Nervous

System

– normally automatic (respiratory

centres in brain stem)

– some voluntary control (cortex

overides respiratory centres)


• Nasal passages• Larynx• Trachea• Bronchi• Bronchioles

• Terminal Bronchioles• Alveolar Ducts• Alveoli

• Gas exchange takes place rapidly in alveoli - large surface area surrounded by dense capillaries

Structure


VENTILATION

Inspiration is active

volume of thoracic cavity by

contraction of intercostal muscles and diaphragm

Expiration (at rest) is passive

volume returned to resting values


LUNG VOLUMES


EFFECTS OF AGING

• Stiffness of chest wall

• Strength of respiratory muscles

• Elastic recoil in lung

• Residual dead space

• Functional area of lung

• Cartilaginous support

• Thickening of mucosal lining

• Sensitivity of respiratory centres


FUNCTIONAL CONSEQUENCES

System still adequate for sub-maximal activity

• Respiratory work

• Oxygen costs of many activities

• Breathlessness may reduce tolerance of

exercise

• maximal voluntary ventilation

• mechanical efficiency of movement

• posture


EFFECTS OF TRAINING

• maximal voluntary ventilation

• mechanical efficiency of movement

• posture

Documents

Specialist PSI Exercise Module CARDIOVASCULAR SYSTEM Main transport system –Gases –Food –Waste –Hormones –Minerals –Medications Heart rate - controlled