TWP Critical Power Calculator - http://www.trainwithpower.co.uk/TestYourself/CriticalTest/tabid/388/language/en-US/Default.aspx

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Training Zones Determination   TWP_Chemise.bmp
     
Critical Power test (20 min)    
     
Power :      
     
     
Intensity Zone Power Accomplishment Perception
LOW 1 - Low Endurance No pain.
Fatigue after 3-4 h
2 - Basic Endurance No pain
Easy to speak
MEDIUM 3 - Tempo First muscular pain
Difficulty to carry out a long conversation
4 - Road Race Progressive increase of muscular pain
Difficulty to carry out a conversation
HIGH 5 - Speed training above threshold Fast increase of muscular pain
Impossible to carry out a conversation
6 - VO2 max training
Anaerobic sprint
Impossible to speak
Exhaustion after effort + overbreathing

http://www.trainwithpower.co.uk/TestYourself/CriticalTest/tabid/388/language/en-US/Default.aspx
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