HSE201 Lecture Notes - Lecture 11: Vo2 Max, Hematocrit, Cardiac Output
Oxygen Delivery & Utilisation
- Limitation is mostly viewed as occurring through delivery rather than utilisation
- Occurs at level of central and peripheral circulation
- Possibly cardiac output (SV)? oxygen diffusion from cap to mitochondria?
- Respiratory system generally not seen as a limitation
- PO2 decreases very little, may be limiting at altitude or in elite endurance athletes at high exercise
intensities
Other factors affecting:
- Body size, larger muscle mass increases VO2MAX
- Age, VO2MAX usually declines with age
- Gender: VO2max lower in females compared to males, smaller heart size so smaller SV, lower
haematocrit which decreases o2 delivery
- Muscle fibre composition: higher proportion of ST oxidative fibres T1 in endurance trained
- State of training
- Fatigue: effects of prior exercise
- VO2 max generally correlates with exercise performance, but other factors may also influence
endurance performance
- EX. Percentage of vo2max that can be sustained determined by lactate threshold
- VO2 max indicates size of the engine the athlete has to work with
Document Summary
Limitation is mostly viewed as occurring through delivery rather than utilisation. Occurs at level of central and peripheral circulation. Respiratory system generally not seen as a limitation. Po2 decreases very little, may be limiting at altitude or in elite endurance athletes at high exercise intensities. Body size, larger muscle mass increases vo2max. Gender: vo2max lower in females compared to males, smaller heart size so smaller sv, lower haematocrit which decreases o2 delivery. Muscle fibre composition: higher proportion of st oxidative fibres t1 in endurance trained. Vo2 max generally correlates with exercise performance, but other factors may also influence endurance performance. Percentage of vo2max that can be sustained determined by lactate threshold.
