User Manual
Joule 2.0 User Guide page 43
Chapter 13: Definition of Terms
Peak Sustainable Power or Peak Power
1. The highest average power output that can be held for a given duration. 2. For most individuals
a peak sustainable power or peak power output lasting 4 to 8 minutes is equivalent to an inten-
sity that elicits their VO2 max, or maximal capacity to consume oxygen. 3. For most individuals a
peak sustainable power output lasting 20 to 40 minutes is equivalent to an intensity that elicits
their lactate threshold or a value of blood lactate 2 to3 mM above their baseline blood lactate. 4.
For most individuals a peak sustainable power output lasting 40 minutes to 2 hours is equivalent
to an intensity that elicits their lactate threshold, or a value of blood lactate just above to 1 mM
above their baseline blood lactate. 5. In cycling, the peak sustainable power for any given dura-
tion is analogous to their best performance for a given time. For example, a runner might have a
personal best of 5 minutes in a mile run and 35 minutes in a 10 km run, whereas a cyclist might
have a personal best or peak sustainable power of 400 watts for 5 minutes and 340 watts for 35
minutes.
Normalized Power
1. An estimate of the power that you could have maintained for the same physiological “cost” if
your power output had been perfectly constant.
Intensity Factor (IF) 1. Ratio of normalized power to power output at threshold. 2. A convenient
way of comparing the relative intensity of a training session or race either within or between
riders, taking into account changes or differences in threshold power. Typical IF values for various
training sessions or races are as follows:
• Lessthan0.75recoveryrides
• 0.75-0.85endurance-pacedtrainingrides
• 0.85-0.95temporides,aerobicandanaerobicintervalworkouts(workandrestperiods
combined), longer (>2.5 h) road races
• 0.95-1.05lactatethresholdintervals(workperiodonly),shorter(<2.5h)roadraces,
criteriums, circuit races, longer (e.g., 40 km) TTs
• 1.05-1.15shorter(e.g.,15km)TTs,trackpointsrace
• Greaterthan1.15prologueTT,trackpursuit,trackmiss-and-out