Final Exam: Week 7 Musculoskeletal Flashcards
Neuromuscular changes with age
↓ muscle strength & power
↓ skeletal muscle mass
↓ number of functional motor units
Changes in postural alignment
Bone and cartilage changes
Changes in balance and gait
↓ max speed of movement and initiation in response to stimuli
↑ threshold for vibration sensation (decreased sensitivity)
↓ proprioception
Physically elite
Train on a regular basis in sports competitions, continue to work in demanding occupation
Physically fit
May still work, may participate in activities with folks younger than them, continue to exercise regularly
Physically independent
Participates in IADLs and is still active in leisure and hobbies. May have one+ chronic conditions, function independently
Physically frail
Lives independently with some assist, may be unable to engage in some IADLs
Physically dependent
Cannot perform some ADL/IADL, requires institutional care or full-time assistance
Strength
Force of muscle contractions and ability to generate force quickly
Power
Timing and coordination
Why do strength and power decrease with aging?
- Decrease in number and diameter in myofibrils and certain types of muscle fibers
- Neurological changes that control muscle contraction
What changes occur in strength?
- Minor until age 60, then becomes more rapid
- Isometric & Concentric strength in UE declines less than LE
What changes occur in power?
- Decreases more quickly than strength
- Example of functional activity that requires power is walking or standing up from a chair – timing and coordination of that muscle contraction
Sarcopenia
Progressive muscle wasting and decrease in strength with aging
Changes in muscle
Less elasticity, more fat, neurological changes, atrophy of some fibers, hypertrophy of others, number of myofibrils
Difference between muscle atrophy and sarcopenia?
Sarcopenia is AGE RELATED
Atrophy is muscle SHRINKING
Elements of physical function
Strength+power+endurance+coordination+balance+flexibility
Ways loss of strength affects physical function in older adults
- Many ADLs and IADLs take power and strength (raking, stairs, exit a car)
- Reduced ability to balance with decreased base of support
- Walking speed slowed, stride length decreased
Why are impairments in muscle power more influential than decreased strength on an older adult’s ADL function and mobility?
Decreases more quickly, standing up or getting up from a chair requires muscle power…lose ability to do simple movements
Decreased LE muscle power correlates with…
Stairs and getting out of chairs
Impaired balance leads to…
More disability
Age-related changes to the bones
- Loss of bone density
- More susceptible to fracture
Age-related changes to cartilage, joints, and tendons
- Cartilage is more dense, stiff, thins out, deteriorates
- Joints and tendons: tighter and less flexible
- Matrices of collagen become denser, the collagen structures become stiffer, and the cellular movement of nutrients and wastes becomes impaired
- ROM decreases 20-30% between ages of 30-70
Osteocytes
Bone maintenance
Osteoblasts
Bone formation
Osteoclasts
Bone resorption
