L2.2 Hormones and Exercise Flashcards
What is the effects of insulin during exercise?
Insulin (anabolic) - ↑exercise → ↓insulin
Insulin causes:
1) ↑muscle glucose uptake
2) activates glycogen synthase
3) Inhibits liver glucose production and lipolysis
What is the effect of glucagon during exercise?
Glucagon (catabolic) - ↑exercise → ↑glucagon
Glucagon causes:
1) ↑liver glycogenolysis
2) ↑Activity of gluconeogenic enzymes in liver
3) ↑lipolysis
What is the effect of exercise on insulin sensitivity?
↑exercise → ↑insulin sensitivity
What is the effect of training and insulin?
↑Muscle oxidative capacity
↑muscle blood flow
↑capillary density recruitment
↑Insulin sensitivity (↑glucose disposal rate)
↑GLUT 4 expression
↑hexokinase, glycogen synthase activity
What is the metabolic action of adrenaline?
↑exercise intensity, duration → ↑A & NA
↑muscle glycogenolysis
↑Liver glucose output
↑lipolysis
↑partly due to dehydration and mainly blood glucose levels
What is the metabolic actions of cortisol during exercise?
a stress hormone – increases during strenuous exercise
↓glucose uptake
↑muscle proteolysis
↑gluconeogenesis & liver glycogen synthesis
↑lipolysis
What is the metabolic actions of Growth hormone during exercise?
stress hormone - increases during strenuous exercise
↑prod. IGF
↓muscles glucose uptake
↑gluconeogenesis
↑lipolysis
↑A.A uptake & protein synthesis
How are hormonal responses regulated?
Motor centres & working muscles send signals to CNS → regulatory responses
What happens to levels of adrenaline if some motor units are paralysed?
If Motor Units are paralysed → CNS has to work harder – therefore has a higher basal adrenaline level, but lower maximal adrenaline level.
What is tissue cross talk?
Contracting muscles secrete myokines – IL-6 – which acts locally and affects other tissues
Exercise → beneficial effect on other organs
