Overweakness and Fatigue Flashcards
Describe Buchner’s curve and it’s relevance
- Buchner’s curve relates function - walking speed (y axis) to strength (x-axis)
- slope looks like a cliff edge
- past a certain threshold of strength, further increases in strength yield no increases in function
- but BELOW that threshold, drops in strength - even small ones - can result in precipitous drops in function
- this can mean the difference between walking VERY slowly - losing strength and not being able to walk at all
Define overwork weakness
PROLONGED reduction in strength and endurance due to EXCESSIVE activity especially ECCENTRIC activity
What are symptoms of overwork weakness?
- DOMS
2. Temporary reduction in max force
Do strengthening execises cause overwork weakness?
NO - unless high intensity performed 4x/week - this is based on Kilmer’s study that increased subjects from 3 to 4x/week
- might be due to less recovery between sessions
What effect do strengthening exercises have on activity and strength?
- improves activity
- effect on strength is inconclusive
How to strengthen without causing overwork weakness?
- no more than 3x/week
- change only 1 training parameter at a time
- monitor for fatigue/exertion/mm soreness
- start SLOW - mod intensity
Define fatigue (in MS)
- a subjective lack of physical + mental energy perceived by the individual or caregiver to interfere with activities of daily living
Characteristics of fatigue in MS
- may be physical/mental
- worse in PM
- agg by heat, depression, pain, excessive exertion
- interferes with physical/social function
Causes of fatigue in MS
- depression
- sleep
- pain
- bladder dysfunction
What are 1º causes of fatigue in MS?
- demyelination
- cortical reorganization
- higher levels of immune markers?
What are 2º causes of fatigue in MS?
- reduced PA causing reduced strength and cardiorespiratory fitness
- heat (0.5º C rise in body temp = heat fatigue)
- anti spasticity meds (reduces force generation of mm’s)
- low sense of control or environment mastery (?)
How is fatigue managed? (list 2 basic ways)
- Acknowledge it as a genuine symptom d/t nervous system damage resulting from the disease
- medications - amantadine (anti viral agent) benefits people with MILD fatigue but has a few SEs (dizziness, nausea, dry mouth, constipation,loss of balance)
- emotional support - Multidisciplinary approach (OT/physio/dietician/psychologist/social worker/pain+sleep clinic etc)
How does the following help to manage fatigue?
- diet
- psychologist
- OT
Diet - low fat/low chol diet = reduction in fatigue impact
Psychologist - mindfullness based training “non-judgemental awareness of experiences” = reduction in fatigue impact and reduces depression and increases QoL
OT - energy conservation course (2hrs/week for 6 wks) = increased self efficacy and reduces fatigue impact
How can physiotherapy help with fatigue?
FITNESS! - address 2º causes of fatigue and increase strength, PA levels, and fitness
What is the effect of exercise on fatigue? On fitness?
Heine et al (2015) (Cochrane SR) - favors exercise training group for reducing fatigue in MS
No evidence that one exercise protocol is superior to another to pick based on patient preference
Platta et al (2016) - exercise improves fitness
