Aeorbic capacity Flashcards
What are the factors affecting aerobic capacity?
Physiological make-up
Age
Gender
Training
Genetics
What is the effect and explanation of physiological make-up on aerobic capacity?
Effect on VO2max - The greater the efficiency of the CV and respiratory systems and muscle cells to inspire and utilise oxygen, the higher the VO2 max
Explanation -
-Large lung volumes and strong respiratory muscles can inspire larger volumes of air
-Size and strength of heart, large left ventricle will have greater contractibility, increase SV and Q, greater transportation rate of oxygenated blood flow
-Increased haemoglobin content of the blood stream will transport more oxygen
-Number of capillaries (capillarisation) will increase the SA for gas exchange
-High percentage of SO muscle fibres rich in myoglobin and mitochondria will produce more energy aerobically
-Asthma
What is the effect and explanation of age on aerobic capacity?
Effect - VO2 max reduces approximately 1% per year from early 20s. But will reduce less for active sportspeople
Explanation - Lost elasticity in the heart, blood vessels and lung tissue walls with age, reducing the efficiency to inspire and transport O2
What is the effect and explanation of gender on aerobic capacity?
Effect - Females tend to have a 15-30% (10-15 ml/kg/min) lower than men from the same age group
Explanation - Women have higher percentage of body fat, smaller lung volumes, smaller heart so reduced SV and Q, and lower blood haemoglobin levels. Men have greater oxygen utilisation capacity, greater mass of slow twitch muscle fibres, greater density of mitochondria
What is the effect and explanation of training on aerobic capacity?
Effect - Aerobic training can cause VO2 max to increase by 10-20%. In ageing performers aerobic training will maintain or reduce or decline in VO2 max
Explanation - Aerobic training causes long-term adaptations, such as increased strength of respiratory muscles, levels of haemoglobin, myoglobin and mitochondria, which increases the efficiency to inspire, transport and utilise oxygen
How does genetics have an effect on VO2 max?
It can account for 93% of the variation in VO2 max.
eg. The difference in fibre type composition, can also influence your response to training
What is capillarisation?
The formation and development of of a network of capillaries to a part of the body, increased through aerobic training
Definition of aerobic capacity
The ability of the body to inspire, transport and utilise oxygen to perform sustained periods of aerobic activity
Definition of VO2 max
The maximum volume of oxygen inspired, transported and utilised per minute during exhaustive exercise
What is VO2 max measured in?
ml/kg/min
What is the average VO2 for a trained and untrained athlete?
Untrained individual- 40-50 ml/kg/min, work to 50-60% of VO2max before fatigue
Aerobic athlete- over 55 ml/kg/min, work to >85% of VO2max before fatigue
What are the tests to measure aerobic capacity?
Direct gas analysis, queens college step test, cooper 12-minute run, NCF multi-stage fitness test
What is the protocol for the direct gas analysis test?
- Performer completes continues exercises at progressive intensities
- Expired air is measured using a mask and gas analyser
- The relative concentrations of O2 and CO2 are measured and compared to atmospheric air
- Results are graphed and equation is used to calculate VO2 max
What are the advantages of the direct gas analysis test?
-Valid/direct measure of VO2 max
-Test can be performed during different exercises (eg. swimming, running, rowing, cycling) and in different setting (eg. laboratory, field)
What are the disadvantages of the direct gas analysis test?
-Maximal test to exhaustion
-Specialist equipment is required
-Not suitable for elderly or those with health conditions
What is the protocol for the NCF multi-stage fitness test?
- Subject performs continuous 20m shuttle runs at progressive intensities to exhaustion in time with an audio cue
- Test goes until subject cannot complete shuttle in allocated time
- Level and shuttle number given, predicts VO2 max using comparison table
What are the advantages of the NCF multi-stage fitness test?
-Large groups can be tested at same time
-Simple and cheap equipment
-Scores easily evaluated in published tables
What are the disadvantages of the NCF multi-stage fitness test?
-Test to exhaustion, limited by subjects motivation
-Prediction of VO2 max, not measure, not 100% accurate
-Not sport specific (eg. rowers, cyclists have a disadvantage)
What is the protocol for the cooper 12 minute run?
- Subject performs continuous running to achieve a maximum distance in 12 minutes, normally on a 400m track
- Total distance is recorded, calculation to predict VO2 max using
What are the advantages of the cooper 12 minute run?
-large groups in a field setting at once
-self-administrable/simple and cheap equipment
-published table of normative data
What are the disadvantages of the cooper 12 minute run?
-prediction of VO2 max, not measurement
-maximal test to exhaustion, limited by subjects motivation
-cannot be done on elderly, or those with health conditions
-not sport specific, eg. rowers, cyclists at a disadvantage
What is the protocol for the queens college step test?
- Continuous stepping on and off a block 41.3cm high for 3 minutes
- Pace set by a metronome, 24 steps per minute for men, 22 for women
- Heart rate is taken 5 seconds after completing for 15 seconds
- HR recovery is used to predict VO2 max using
What are the advantages of the queens college step test?
-submaximal test
-simple and cheap equipment
-HR easily monitored
-Published table of normative data
What are the disadvantages of the queens college step test?
-prediction of VO2max, not a measure
-HR recovery affect by prior exercise, food, fluid intake
-Not sport specific (eg. rowers, cyclists) at a disadvantage
-Step height may be a disadvantage to shorter subjects
Why is HIIT training considered more effective than continuous training?
-higher calorie consumption/greater fat burning
-fast/more adaptations to training
-performers can train at higher intensity for longer
-training time/durations shorter and quicker sessions for similar gains
-individuals with different fitness levels can training together in group/class session
Describe a high intensity interval training (HITT) session to improve aerobic capacity
-Periods of high intensity work followed by rest periods/recovery
-20-60 minutes
-Cross training, cycling, running, boxing, jumping, swimming
-Work intensity 80-95% of max HR, 70-90% VO2max
-Work duration, 5 seconds to 8 minutes
-4-10 sets/ 10+ reps
-Recovery intensity is lower, 40-50% of max HR
-1:0.5 work to relief ratio
