exercise after stroke specialist instructor training course l5 physical fitness after stroke...
TRANSCRIPT
EXERCISE AFTER STROKESpecialist Instructor Training Course
L5Physical fitness after stroke
background
Overview of talk
• Physical activity and fitness defined
• Components of physical fitness
• Impact of stroke on fitness
• Relation between fitness and function after stroke
• The need for exercise!
Learning outcomes
After this session you should be able to:
• Define “physical fitness”
• Describe and explain the impact of stroke on fitness
• Describe and explain the impact of reduced fitness on function after stroke
Physical activity
• All bodily movement produced by the contraction of skeletal muscle and which substantially increases energy expenditure (USDHHS 1996)
• Includes the muscular work required for – Walking– Maintaining posture – Activities of daily living– Occupational, leisure and sporting activities
What happens to physical activity after stroke?
• After major stroke, patients are often immobile due to the neurological effects of stroke
• Stroke in-patients: only 13% of time engaged in physical activity (Bernhardt 2004)
• Even relatively minor neurological deficits may lead to a reduction in physical activity
• Paucity of literature on levels of physical activity after stroke, particularly after minor stroke
ActivPalTM physical activity monitoring
Physical fitness………….
Is a set of attributes, which people have or achieve, that relate to the ability to perform physical activity (USDHHS 1996)
Is improved by activity and reduced by inactivity
Physical fitness essential for physical activity
Cardiorespiratory
Muscle strength and power
Components of physical fitness Cardiorespiratory fitness Relates to an individual's ability to perform physical activity for an extended
period. Conferred by Central capacity of the circulatory and respiratory systems to supply oxygen
(USDHHS 1996)Peripheral capacity of skeletal muscle to utilise oxygen (Saltin & Rowell
1980).
Muscle strength Maximum force that can be generated by a muscle or muscle groupAbility to sustain repeated muscular actions or a single static contraction is 'muscular endurance' (USDHHS 1996)
Muscle powerRate of generation of strength
Body composition Includes total and regional bone mineral density, and the relative amounts and distribution of adipose tissue, muscle and other vital parts of the body (USDHHS 1996).
What happens to physical fitness after stroke?
• Physical fitness is related to physical activity
• After stroke, activity falls
• So might physical fitness be reduced?
Aerobic fitness (endurance) after stroke
Bachynski1985
Mackay et al.2002
Fujitaniet al 2001
Duncan2003
Kelly 2003
0%
20%
40%
60%
80%
100%
120%
1 10 100 1000 10000
Time since stroke (days)
% A
ge-M
atch
ed P
opul
atio
n M
ean
Potempaet al. 1995
Macko et al
2001
Rimmeret al. 2001da Cunha
et al. 2001
Ryanet al2001
Eng 2004
Pang 2004
Peak V02 synthesised from 16 studies (Dave Saunders 2007 unpublished)
Muscle strength and power after stroke
We recruited 11 patients who had made an apparently full neurological recovery several months after their stroke
We measured – Muscle strength – Power output of both lower limbs
We found that muscle strength and power output in both limbs were significantly lower than age and sex matched values from the population
Greig et al 2001
Measurement of maximum voluntary isometric knee extensor strength
Measurement of lower limb extensor power during a single maximal leg extension
Might these impairments in aerobic fitness, muscle strength and
muscle power have consequences for function, mobility, quality of life?
Influence of impaired leg extensor power on
function after stroke? • In 66 ambulatory patients, who had completed their
rehabilitation, there were associations between impaired LEP in both the affected and unaffected limbs and – Timed up and go– Sit to stand– Functional reach– Comfortable walking velocity – FIM– Rivermead motor index– Nottingham extended ADL– SF36– Elderly mobility scale (Saunders et al 2008)
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LEP (WKg-1)
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)
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LEP (WKg-1)
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-m u
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LEP (WKg-1)
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.sec
-1)
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LEP (WKg-1)
Cha
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ec)
LEP and function in 66 people after stroke (STARTER)
Affected (■) and unaffected (□) legs
Relationship between aerobic fitness and function
• 74 people with chronic hemiparetic stroke demonstrated that walking ability was independently related to – Cardiovascular fitness– balance– paretic leg strength
Patterson 2007
Why is fitness impaired after stroke?
• Reduced physical activity after stroke
• Reduction in fitness may pre-date stroke (age and co-morbidities)
• Direct effect of hemiparesis
Mechanisms of reduced fitness after stroke
FitnessImpairments
PhysicalInactivity
FunctionalLimitations
DISABILITY
OtherImpairments
Process ofDisablement
Cycle ofDetraining
STROKEPathology
Increasing Age
Comorbid Disease
Direct Effectof Stroke
Courtesy Dave Saunders 2008
Summary
• Physical fitness is reduced after stroke– Muscle strength– Muscle power– Aerobic fitness
• Mechanisms include – Direct effect of hemiparesis– Pre-stroke impairments – Reduced physical activity after stroke
• Impairments in physical fitness are associated with reductions in functional ability
Essential ReadingFurther detail about the topics discussed in this
session can be found in section L5 of the course syllabus.