You’ve probably noticed a few numbers appear on your training stats but apart from watts, bpm and FTP very few know what they mean so let me explain – I’ll take them in the usual order they appear.
Intensity Factor – IF
NP ÷ FTP
[NP = Normalised Power is similar to average power but with power spikes smoothed it’s a better measure of ride with variable effort.
Typical IF values for various training sessions or races are:
Less than 0.75 recovery rides
0.75-0.85 endurance-paced training rides
0.85-0.95 tempo rides, aerobic and anaerobic interval workouts (work and rest periods combined), longer (>2.5 h) road races
0.95-1.05 lactate threshold intervals, shorter (<2.5 h) road races, criteriums, circuit races, longer (25m) TTs
1.05-1.15 shorter (10m) TTs, track points race
Greater than 1.15 track pursuit, track elimination races
Variability Index - VI
NP ÷ Average Power
Typical values to look for:
Steady endurance ride 1.00-1.02
Flat Road Race 1.00-1.06
Flat Time Trial 1.00-1.08
Flat Criterium 1.06-1.35
Hilly Road Race 1.20-1.35
Cyclocross Race 1.13-1.50
Efficiency Factor – EF
NP ÷ Average Heart Rate
To put it simply decoupling. It shows how hard your heart is working for a relative effort. Typical scores? Ah there’s the problem, its specific to your numbers and you need to establish a trend and can only compare with similar workouts. As you become more efficient score will increase.