Respiratory exchange ratio
What Respiratory exchange ratio means in Physical Education A-Level, as defined for AQA.
Definitions of Respiratory exchange ratio
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Reference: AQA
Calculated as carbon dioxide production divided by oxygen uptake, it indicates the substrate mix: near 0.7 suggests mainly fat oxidation, near 1.0 mainly carbohydrate, and above 1.0 a heavy anaerobic contribution.
A value calculated by software from recorded ventilation and gas concentrations alongside oxygen consumption.
Topics that use Respiratory exchange ratio
- Energy systems (AQA A-Level)
- The role of technology in physical activity and sport (AQA A-Level)
Related terms
- Indirect calorimetry
- Absolute and relative values
- Access, participation and performance
- Adaptation for age
- Adaptation for disability
- Aerobic and anaerobic adaptation
- Aerobic energy system and endurance performance
- Aerobic energy transfer
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