VO2 max/aerobic capacity Flashcards
Definition of VO2 max
The highest rate of oxygen consumption attainable during maximal activity
Therefore, an ability to work at a high percent of VO2 max (below anaerobic threshold) is a good indicator of aerobic endurance
What is the PWC170 test
Sub-maximal test on a cycle ergometer
Performer cycles at 3 progressive low-to-moderate work intensities (100-115,115-130,140-145bpm) and their heart rate values are recorded
As HR increases linearly with work intensity, a line can be drawn through these points on a graph, which can be extended to predict the intensity level that they should be working at when heir HR reaches 160bpm
This figure is chosen as an appropriate anaerobic, close to maximal, level of work based on the assumption that VO2 max is close linked to maximal HR
What is the multi-stage fitness test
Progressive and maximal 20metre shuttle run test, with the 20m distance timed by a beep which progressively becomes shorter until the athlete cannot keep up or drops out
This provides a level and shuttle number score which is then compared with standardised tables to estimate/predict a VO2 max value for males and females
What is the most accurate way of testing VO2 max
Gas analysis test
What are the four factors that affect VO2 max
Heredity
Age
Gender
Specificity of training
Explain how heredity affects VO2 max
Genetics can account for up to 50% of the variation of VO2 max
Eg having a higher percent of type 1 and type 2a muscles fibres would be an advantage for aerobic performance
However, heredity only indicates potential to have a higher VO2 max -the development is dependent on aerobic training
Explain how age affects VO2 max
As a general rule, VO2 max decreases approx. 1% per year due to a decrease in efficiency of the body’s systems
Two main causes:
1. CV performance - MHR, SV and Q all decrease due to decreased left ventricular contractions/elasticity
2. Respiratory - lung capacity decreases after maturation due to a decrease in the elasticity of lung tissue
However, continued aerobic training will minimise this
Explain how specificity of training affects VO2 max
Methods: altitude, continuous, interval, fartlek
Adaptations:
1. Skeletal - increase cartilage strength, increase bone density along the bone
2. Muscular - reduce lactic acid, type 2B take on type 2A characteristics (fast twitch becomes more aerobic)
3. Respiratory - higher tidal volume, stronger respiratory muscles (diaphragm and intercostals)
4. Cardiovascular - increase I’m heart size (left ventricle), decrease in resting heart rate
5. Health and active lifestyle - reduced body fat, increase in BMR
Explain how gender affects VO2 max
VO2 max values for women are generally 20-25% lower than for men due to women having a higher percent of body fat (VO2 max is measured per kg of body mass)
Women have a smaller body size, so they also have:
1. Smaller lung volumes
2. Smaller hearts leading to increased RHR and lower SV
3. Lower haemoglobin levels that decrease O2 transport and blood flow
What are the three fitness tests for VO2 max
PWC170
Multi-stage fitness test
Gas analysis test
