LEC15: Sensory System (Age-Related Changes in Physiology and the Effects of Exercise)

Question 1

Fall Statistics: between (blank) of Canadians aged 65 and over fall each year

Answer 1

20-30%

Question 2

Fall Statistics: falls remain the leading cause of (blank) among Canadians aged 65 and over

Answer 2

injury-related hospitalizations

Question 3

Fall Statistics: falls are the direct cause of (blank) of all hip fractures, leading to death in (blank) of cases

Answer 3

95%, 20%

Question 4

Fall Statistics: falls appear to be a catalyst for what?

Answer 4

The transition to long-term care

Question 5

Activity associated with fall-related injury, age 65+

Answer 5

Walking in any other surface: 45%
Walking on snow or ice: 16%
Up or down stairs/steps: 13%
Due to health problems: 8%
From furniture/rising from furniture: 5%
From elevated position: 5%
Engaged in other sport or physical activity: 4%
Other (includes skating, skiing, and snowboarding): 4%

Question 6

Body part affected by fall-related injury, age 65+

Answer 6

Knee, lower leg: 15%
Ankle, foot: 10%
Lower back or lower spine: 8%
Wrist: 8%
Hip: 7%
Head (including facial bones): 7%
Chest: 7%
Hand: 4%
Elbow, lower arm: 4%
Multiple sites: 4%
Abdomen or pelvis: 3%
Neck, upper back or upper spine: 3%
Thigh: 2%
Eyes (excluding facial bones): 1%

Question 7

Fall-related hospitalizations, by place of occurrence of fall, age 65+

Answer 7

Home: 50%
Residential Institution: 17%
Sports and athletic area: 0%
Industrial and construction: 0%
School, other institution, public area: 7%
Street and highway: 3%
Trade and service area: 2%
Other specified place: 2%
Farm: 0%
Unspecified place: 19%

Question 8

Biological/intrinsic factors associated with an increased risk of falling among older adults

Answer 8

1. Impaired mobility
2. Balance deficit
3. Gait deficit
4. Muscle weakness
5. Advanced age
6. Chronic illness/disability:
   a. Cognitive impairment
   b. Stroke
   c. Parkinson’s disease
   d. Diabetes
   e. Arthritis
   f. Heart disease
   g. Incontinence
   h. Foot disorders
   i. Visual impairment
7. Acute illness

Question 9

Behavioural factors associated with an increased risk of falling among older adults

Answer 9

1. History of falls
2. Fear of falling
3. Multiple medications
4. Use of:
   a. Antipsychotics
   b. Sedative/hypnotics
   c. Antidepressants
5. Excessive alcohol
6. Risk-taking behaviours
7. Lack of exercise
8. Inappropriate footwear/clothing
9. Inappropriate assistive devices use
10. Poor nutrition or hydration
11. Lack of sleep

Question 10

Social and Economic factors associated with an increased risk of falling among older adults

Answer 10

1. Low income
2. Lower level of education
3. Illiteracy/language barriers
4. Poor living conditions
5. Living alone
6. Lack of support networks and social interaction
7. Lack of transportation
8. Cultural/ethnicity

Question 11

Environmental factors associated with an increased risk of falling among older adults

Answer 11

1. Poor building design and/or maintenance
2. Inadequate building codes
3. Stairs
4. Home hazards
5. Lack of:
   a. Handrails
   b. Curb ramps
   c. Rest areas
   d. Grab bars
   e. Good lighting or sharp contracts
6. Slippery or uneven surfaces
7. Obstacles and tripping hazards

Question 12

What are the systems contributing to balance?

Answer 12

1. Sensory (visual, somatosensory, vestibular)
2. Cognitive
3. Motor
4. Older adults and balance dysfunction

Question 13

What is the sensory system?

Answer 13

Brings in information about the state of the body in relation to the environment and task

Question 14

What is the cognitive system?

Answer 14

Makes the decision about what action is needed

Question 15

What is the motor system?

Answer 15

Produces the actions required to maintain or restore balance

Question 16

What are the changes to the visual system with age?

Answer 16

1. Reduced acuity
2. Reduced contrast sensitivity
3. Reduced depth perception
4. A narrowing of the visual field (particularly in the peripheral region)

Question 17

What are the changes to the somatosensory system with age?

Answer 17

1. Sensitivity to the cutaneous receptors to touch and pressure decreases
2. Number of sensory pathways innervating the cutaneous receptors also decreases
3. Older adults experience a 2-10 fold increase in vibration threshold needed to detect sensations of touch (this results in a reduced ability to feel the quality of the contact between the feet and the surface below)

Question 18

What are the changes to the vestibular system with age?

Answer 18

1. By the age of 70, the number of vestibular hair and nerve cells have declined up to 40%
2. A moderate reduction in the gain of the vestibulo-ocular reflex

Question 19

What is the vestibulo-ocular reflex responsible for?

Answer 19

This reflex is responsible for stabilizing vision when the head moves quickly through a space or when there are many moving parts in a space

Question 20

What are the changes to the cognitive system changes with age

Answer 20

1. Deficits in attention, memory, and intelligence become more common with age
2. Dual task situations have been found to be particularly challenging for older adults

Question 21

What are the changes in motor system changes with age?

Answer 21

1. Decreased strength, power, and endurance
2. Increased time spent in the action planning phase (Increased reaction time, movement time, and response time)

Question 22

What is the action planning phase?

Answer 22

The time to process incoming sensory information and formulate an appropriate motor response

Question 23

Does exercise reduce the rate of falls in community-dwelling older adults?

Answer 23

Yes. Meta-analysis showed 21% reduction in fall risk based on 88 studies involving ~19 000 participants

Question 24

Exercise as a single (stand alone) intervention in community-dwelling older adults has a fall prevention effect similar to (blank)

Answer 24

Multi-faceted interventions. Exercise may be more easily implementable and cost-effective compared to multi-faceted interventions

Question 25

What are the two things which show the best reduction in fall rates?

Answer 25

1. The exercises prescribed provided a high challenge to balance
2. Participants were exercising for 3 or more hours each week

Question 26

What are some exercise programs which aim to provide a high challenge to balance?

Answer 26

1. Reducing the base of support (eg, standing with two legs close together, standing with one foot directly in front of the other, standing on one leg)
2. Moving the centre of gravity and controlling body position while standing (eg, reaching, transferring body weight from one leg to another, stepping up onto a higher surface)
3. Standing without using the arms for support, or if this is not possible then aim to reduce reliance on the upper limbs (eg, hold onto a surface with one hand rather than two, or one finger instead of the whole hand)

Question 27

(blank) training may be included in addition to balance training

Answer 27

Strength, walking

Question 28

(blank) in balance training is necessary or the benefits will be lost

Answer 28

On-going participation

Question 29

ACSM position statement on older adults and physical activity states that balance exercises should include the following:

Answer 29

1. Progressively difficult postures that gradually reduce the base of support (eg, two-legged stand, tandem stand, one-legged stand)
2. Dynamic movements that perturb the center of gravity (eg, tandem walk)
3. Stressing postural muscle groups (eg, heel stands, toe stands)
4. Reducing sensory input (eg, standing with eyes closed)