Lecture 4 Flashcards
Why are we more prone to injuries when we stretch?
Most injuries occur during the eccentric portion of the stretch-shortening cycle for a normal range of motion.
What did Archibald Vivian Hall demonstrate?
(VO2 max) Demonstrated that oxygen uptake increased linearly with running speed, but eventually reaches a maximum beyond which no effort can drive it.
What is VO2 max?
The maximum rate of O2 consumption via oxidative phosphorylation during whole body, dynamic exercise.
Is someone’s VO2 max always constant?
No
1) it’s specific to the task- it depends on the musculature involved and therefore the amount of oxygen needed.
2) VO2 max will decline with age.
Where do you see the highest scores in VO2 max? What does it mean if you have a genetically high VO2 max?
1) cross-country skiers
2) means you have an advantage or are better at endurance sports.
What is important to remember when considering the benefit of VO2 max training on performance?
It can max out after 3-4 months of training. Performance can still increase so its not the only factor that effects and can improve performance.
Why does VO2 max increase.
1) Central adaptations - increase in cardiac output.
2) Peripheral adaptations - extracting more oxygen from the blood stream.
What is the lactate threshold?
Intensity corresponding to the onset of blood lactate accumulation.
Why is having a high lactate threshold beneficial?
This means that an athlete can be maintain a higher intensity during a game for a longer amount of time.
What does lactate threshold increase?
Submaximal performance.
What is the single best correlate with endurance performance?
Speed at the lactate threshold.
Why does lactate threshold take longer to improve? What can result from this improvement?
It’s longer to get peripheral adaptations but can get lactate threshold to be around 85% of VO2 max- huge benefit! Equal to old VO2max you had before training.
What is running economoy? What is it determined by?
The energy demand for a given velocity of runnning. Determined by stead-state VO2 vs speed.
What does it mean to have a high running economy?
A lower Vo2 at a given speed for runners compared to other runners with the same speed.
What contributes to one having a high running economy?
Less body hair- induces better thermoregulation.
Aspect ratio- ratio between height and weight - angular.
Thin long bones- less air resistance.
Anatomy of foot- rounded heels, longer toes = a bit more spring.
