EIMD

Question 1

What’s the general process of EIMD

Answer 1

Initial event - mechanical eg. Resistance exercise - high tension
- metabolic eg. Cycling - high temp, lower pH, free rads, Insuff mitochondrial resp

Loss of Ca homeostasis

Autogenic process

Phagocytosis

Regeneration/repair

Question 2

Why do we see more damage with ecc muscle contractions?

Answer 2

They have greater force production, longer muscle length, lower metabolic cost and high mechanical strain per fibre (as you recruit less)

Question 3

What makes up the autogenic process?

Answer 3

Myofibrillar protein degradation, membrane degradation, lysosomal proteases, free rad O2 species, leukocytes and cytokines

Question 4

What occurs in regeneration?

Answer 4

Satellite cells are stimulated via macrophages, IGF-1, IL-6 and mTORC activation and repair the muscle fibre(s)

Question 5

What are direct markers of EIMD?

Answer 5

Biopsy

Question 6

What are the indirect markers of EIMD?

Answer 6

Reduced muscle function, 
DOMS,
Increase in intracellular proteins in blood eg. Ck
Reduced ROM
Swelling,
Markers of inflammation,
Markers of ox

Question 7

mTOR mechanism

Answer 7

mTORC1 upregulates S6K and downregulates 4E-BPI.

These upregulate protein synthesis and ribosomal biogenesis that lead to hypertrophy

Question 8

What upregulates mTOR?

Answer 8

IGF-1, cytokines, mechanical stress

Question 9

What mechanisms lead to hypertrophy?

Answer 9

Satellite cell activation,
mTOR,
IGF-1 signalling pathway