Week 6 - Energy Systems II Flashcards
Which energy system can be measured directly and precisely?
The aerobic system
How are the other energy systems assessed?
They are assessed indirectly, relying on maximal efforts
What does alactic power and capacity refer to?
Energy from ATP-PC stores and the phosphate system
What does anaerobic power and capacity refer to?
Energy from both the phosphate and lactate systems
What is the difference between power and capacity in the context of energy systems?
- Power refers to peak output (rate of use)
- Capacity refers to total output over time
How is alactic anaerobic power assessed?
Through maximal effort exercises, especially for activities lasting 1-6 seconds
What energy systems are primarily used for maximal activities lasting 1-2 seconds?
ATP stores in muscles are the primary source of energy
What energy systems are primarily used for maximal activities lasting 3-6 seconds?
The ATP-PC system (ATP stores & phosphocreatine)
What tests are used to assess alactic power?
- 1, 3, 5 RM strength tests
- Vertical jump
- Standing broad jump
- Short sprints (40m/40 yd dash, 25m swim)
- Margaria-Kalamen stair run
What does total work performed during a maximal 10s exercise test measure?
It measures alactic capacity, which reflects the total work that can be performed by the ATP-PC system operating maximally
How is peak alactic power determined in a 10s test?
Peak alactic power is indicated by the peak 1-second value obtained during the test
When is peak power typically observed in a 10s maximal exercise test?
Peak power is typically observed during the first 5 seconds of the test
How is peak alactic power assessed in a 10s cycle test?
The peak power output (absolute in watts and relative in watts per kilogram) obtained from pedaling all out for 10 seconds indicates peak alactic power
How does a 100m sprint measure alactic capacity?
The time for the 100m sprint indicates alactic capacity, and split times (5 or 10m intervals) can determine peak velocity and peak acceleration, which are indicators of alactic power
What does the Wingate Test assess?
The Wingate Test is a 30-second maximal cycle test that measures peak power output (alactic power) and anaerobic capacity from the ATP-PC and glycolytic systems
How is anaerobic capacity measured in the Wingate Test?
Anaerobic capacity is measured by the average power output over 30 seconds, reflecting the total work performed during the test (capacity to provide energy from ATP-PC and glycolytic systems)
What is the AIS (1991) Anaerobic Treadmill Test designed to assess?
It is designed to assess middle-distance runners’ anaerobic capacity by measuring time to exhaustion at a 10% grade and specific speeds (18kph for males, 16kph for females)
What does the 300m Shuttle Run Test involve?
It involves 20m x 15 shuttles at maximal effort to assess anaerobic capacity
What is peak anaerobic power always equal to?
Peak anaerobic power is always peak alactic power
How is alactic capacity typically measured?
Alactic capacity is typically measured by total work (or average power output) over 10 seconds
What is the duration range for measuring anaerobic capacity?
Between 30 seconds and 3 minutes
What are the approaches to testing peak aerobic power?
Direct measurement of VO2max and indirect tests (progressive tests, maximal work for time or distance, submaximal tests)
What equipment is traditionally used for direct VO2max measurement?
It is traditionally performed on an ergometer, such as a treadmill, cycle, or rower
How can VO2max be measured in the field?
Portable devices enable field-based measurement, including oxygen cost of daily activities
What are the units for reporting VO2max values?
- Absolute (mL/min)
- Relative to body weight (mL/kg/min)
What is the primary criterion for determining VO2max?
VO2 levels off with an increase in workload
What is the secondary criterion related to VO2max determination regarding RER?
An RER value greater than 1.10 or 1.15, indicating buffering due to anaerobic contribution
What is the significance of blood lactate concentration in determining VO2max?
- For 20-49 years: ≥ 7.0 mmol/L-1 for females and ≥ 9.0 mmol/L-1 for males.
- Indicates anaerobic metabolism contribution.
How does age-predicted maximum heart rate factor into VO2max determination?
The heart rate should reach the age-predicted maximum (220-age) ± 10 beats/min
What is the criteria related to VO2 levels for determining VO2max?
If VO2 increases by less than 150 mL O2/min or less than 2.1 mL O2/kg/min with a 2.5% increase in grade
What does an RER value greater than 1.05 indicate during VO2max testing?
An RER > 1.05 indicates anaerobic contribution and H+ buffering during the energy supply
Why is the appearance of voluntary exhaustion not a reliable criterion for VO2max?
It is subjective and unreliable, with signs such as loss of color or nausea being observed
What is the significance of controlling workload during progressive tests for VO2max?
Precise control of workload is essential for accurate prediction of VO2max
Name some common progressive tests used to predict VO2max
- Multistage shuttle run test (beep test)
- Progressive step test
- Progressive cycle tests
- 7-stage swim test
What is a key characteristic of both Time for Distance and Distance for Time tests?
Both require maximal effort
What do submaximal aerobic tests rely on to assess performance?
Submaximal tests rely heavily on heart rate responses
What is the key difference in energy systems between children and adults?
Children are relatively more aerobic and have lower anaerobic capacities until puberty
What are some characteristics of children’s energy systems before puberty?
- Lower ATP-PC stores
- Lower oxygen deficits
- Lower peak blood lactate levels
- Lactate levels rise at similar relative intensities as adults
Why are female values for anaerobic and aerobic performance typically lower than male values?
Females generally have smaller muscle mass, leading to lower ATP, PC stores, and peak lactate levels
