Lecture 11: Energy Metabolism during Exercise

Question 1

role of calcium ions in muscle contraction

Answer 1

• increase in Ca2+ ions signals for muscle contraction
• increases muscle glycogen breakdown by activating glycogen phosphorylase
• stimulates production of NO which causes vasodilation and increased blood flow

Question 2

what affects blood flow

Answer 2

• tissue hypoxia
• adenosine
• K+
• CO2
• H+
• NO
• vascular beta 2 adrenoreceptors stimulated by adrenaline

Question 3

in which cycle is lactate metabolised and where

Answer 3

• Cori cycle

- in liver

Question 4

what are the ways of generating ATP

Answer 4

• phosphocreatine
• anaerobic glycolysis
• aerobic glycolysis and ox phos
• aerobic metabolism with ox phos of glucose and fatty acids

Question 5

at what point in a marathon are glycogen stores depleted and how can this be counteracted

Answer 5

• 20 miles

- carbohydrate loading