Lecture 36: Exercise Physiology Across the Lifespan Flashcards
What is the effect of ageing on VO2max?
Decreases with age
What is the effect of age on heart structure and function?
Increased wall thickness due to increased collagen
Reduced compliance of heart
Lower EDV during exercise
How can exercise training affect heart structure and function in older individuals?
Increases heart compliance, therefore a greater EDV and therefore stroke volume
How does heart rate regulation by the autonomous nervous system change with age?
Decreased parasympathetic stimulation at rest (higher resting heart rate)
Reduced sympathetic drive (ability to raise heart rate when exercising)
What is the effect of exercise on the regulation of parasympathetic tone via the autonomous nervous system?
It increases parasympathetic nerve activity
What happens to the sympathetic stimulation of heart rate with ageing?
The ability to increase heart rate via sympathetic nerve stimulation decreases with exercise
What are the overall physiological adaptations to the heart with ageing, and how can exercise training alter these adaptations?
Structure:
Increase in left ventricle mass (increased wall thickness due to collagen)
Exercise will increase left ventricle mass further, but compliance will increase
Function:
Less diastolic filling due to less compliance
Exercise causes increased compliance
Neural:
Exercise decreases parasympathetic tone (increases resting HR) and decreases sympathetic drive (ability to raise heart rate during exercise)
Exercise will increase the parasympathetic tone of the heart
What happens to artery structure and function with ageing, and how can this be affected by regular exercise training?
Structure:
Increased wall thickness and sub-collagen, decreased elastin
Function:
Decreased compliance and endothelial function
Exercise training causes increased compliance and endothelial function
What is the mechanism by which artery compliance decreases?
Inflammatory cytokines that increase due to ageing detach eNOS, which causes a decreased ability to vasodilate (endothelial function)
What happens to VO2 max throughout childhood in boys and girls?
Boys: VO2 max increases through childhood and is then maintained as they progress
Girls: see an increase in VO2 max through childhood, which drops off due to body changes
How does economy of movement differ in children and adults?
Children have a higher economy of movement (more O2 consumption)
This could be due to technique and/or a lower metabolic reserve
What is the difference in anaerobic power between children and adults?
Children have a lower relative anaerobic power per kg of body mass
How do haemodynamic responses to exercise differ in children and adults?
Children have a lower stroke volume, but have a higher heart rate and oxygen extraction
How does the trainability of aerobic capacity differ between children and adults?
Children have a lower increase in aerobic capacity with training
What are the overall differences in child and adult physiology?
Children have a lower anaerobic power
Children have a lower aerobic trainability
Children have a lower stroke volume in sub-max exercise
Children have a higher heart rate and oxygen extraction in sub-max exercise
Children have a higher economy of movement
