VO2 Max (factors explained)

Question 1

GENDER

Answer 1

• The average male is larger than the average female, therefore they have….
  
  1. A larger left ventricle and therefore a larger stroke volume.
  2. A higher maximum cardiac output (Q): Remember Q= SV x HR
  3. A higher blood volume meaning higher haemoglobin levels.
  4. Higher tidal and ventilatory volumes (more hair per breath).

Question 2

AGE

Answer 2

• As we get older our VO2 max declines as our body systems become less efficient.
  
  1. Max HR drops around 5-7 beats per decade (Lower HR range).
  2. Blood pressure increases
     
     • Hardening of arteries due to loss of elasticity (calcification).
  3. Decrease in stroke volume due to an increase in peripheral resistance (resistance to blood flow).
  4. Decline in vital capacity (max air out after max air in) and an increase in residual air (air that cannot be expelled)- lungs less efficient.
• 18-28= prime/ peak age VO2 max

Question 3

LIFESTYLE

Answer 3

• Smoking: decrease in alveoli, cilia breakdown= mucus development= effects gaseous exchange.
• Sedentary lifestyle: training/ active lifestyle (3 areas= Respiratory, Circulatory, Muscular).
• Poor diet: excess weight= work anaerobically earlier, and more excess energy required.

Question 4

GENETICS

Answer 4

Muscle fibre type:
- Slow twitch muscle fibres= higher VO2 max (work aerobically, lots of O2 available).

Question 5

BODY COMPOSITION

Answer 5

• Fat is seen as non-functional weight.
• Fats need to be carried around, therefore the heavier you are the more O2 is needed to provide the extra energy to sustain a steady state.

Question 6

TRAINING

Answer 6

• VO2 max can be improved by up to 10-20% following a period of aerobic training due to these physiological adaptions.
• Increased MAXIMUM cardiac output (Q)
• Increased stroke volume/ ejection fraction.
• Lower resting HR/ Bradycardia.
• Cardiac hypertrophy.
• Increased blood volume and haemoglobin.
• Increased stores of glycogen and triglycerides.
• Increased capillarisation.
• Increased A-VO2 diff.
• Increased number and size of mitochondria.
• Increased concentrations of oxidative enzymes.
• Increased lactate tolerance.
• Slow twitch hypertrophy.
• Increased myoglobin content.