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Flashcards in Lecture 31 Deck (22)
1

What is sarcopenia?

Age-related muscle wasting

2

What is cachexia?

A component of sarcopenia, but not the same

3

Where does sarcopenia occur most in?

Bedridden, slow walking speed, and those with significant atrophy

4

What are the effects of sarcopenia?

low muscle mass
low muscle strength
low physical performance

5

Who does sarcopenis occur most in?

sarcopenia doesnt discriminate against almost anyone, everyone will develop it regardless of their background

6

What is the effect of age on performance?

Gradual decrease, even in those that train

7

What does sarcopenia look like?

Diminished cross sectional area and infiltrating connective tissue

8

When is the onset of sarcopenia?

~50 years old

9

Which is affected more by sarcopenia, fast or slow muscles?

fast, undergo most atrophy
increases type 1 fibre proportion

10

Name some factors controlling muscle mass as we age

Nutrition
Hormones & genetics
Innervation
Inflammation
Oxidative stress
Blood flow
Exercise
Disease
Protein synthesis & degredation

11

What kind of disease is sarcopenia?

neuromuscular syndrome

12

What is believed to happen in sarcopenia?

Neural supply to fast fibres is lost, resulting in muscle wasting, as well as remodelling many to type 1 fibres

13

What are the possible causes of sarcopenia?

loss of signals from nerves to muscles
or
loss of signals from muscles to nerves

14

What is the effect of age on contracting?

impaired release and reuptake of Ca2+, results in slower contraction

15

What happens in neural connections to muscles with age?

Motor neurons are lost, especially in type 2 fibres
Some neurons can give out branches called sprouts, reinnervating type 2 fibres by a type 1 neuron, converting it to type 1

16

What changes occur in nerves during sarcopenia?

widened nerve end plates
longer nerve terminals
fewer side branches
motor end plates usually undergo constant remodelling

17

Is sarcopenia inevitable?

Yes, it will happen to everyone eventually

18

How can sarcopenia be attenuated?

Strength training, flexibility, balance and aerobic exercise for the elderly to increase their strength and increase hypertrophy
Suggests adaptive capacity remains
Neither reverses sarcopenia damage nor stops it however

19

Does sarcopenia attenuation reverse damage?

No, has only therapeutic effect

20

What is the effect of aging on hormones?

Many growth hormone levels decrease, reducing capacity to repair damaged cells

21

Does growth hormone administration reduce sarcopenia?

No, mostly because they are not coupled with exercise training, little effect on its own

22

What is the best intervention for sarcopenia?

Reducing the disease burden by increasing strength and physical function over increasing lean mass. They dont need mammoth muscles, just normal adult sized so they can rely on themselves