Manipulating substrate availability to alter the exercise induced training response

Question 1

What did De Bock et al 2005 find out about exercising in a carb fasted state?

Answer 1

Carrying out endurance exercise in a carb-fasted state, you see a decrease in post-exercise lipid content in muscle (type I)

When we carry out exercise in a fasted state we are burning fat.

Question 2

What happens to AMPK levels in a fasted state?

Answer 2

Increase - AMPK is activated when AMP levels are high = during exercise or nutrition depletion.

Question 3

What does Wang et al 2004 tell us about the regulation of muscle fibre type + running endurance by PPAR delta?

Answer 3

Transgenic (more type I) animals are far more endurance trained and can run for longer.
Null = PPAR delta inhibited = decreased exercise capacity
- Activated PPAR delta = greater conversion to type I fibres (associated with MB, fat oxidation, endurance capacity).

Question 4

What does Narkar et al 2008 tell us about PPAR delta activation?

Answer 4

Hard to get high activation naturally. We can use drugs to specifically activate PPAR delta.

PPAR delta activation + exercise training increase similar patterns of gene expression in skeletal muscle.

AMPK is activated in muscle in response to exercise and transgenic activation of PPAR delta.