6-Second sprint test

My approach to holding 4 watts per kilo for an hour (FTP) on the bike has been to get strong, convert that to power on the bike, and then work to hold it for longer. First, I built up my strength with weight training with a target of a one and a half times bodyweight squat, and now I am working on building my power on the bike. But how much power do I need before focusing on maintaining that power for more extended periods?

Dr Andrew Coggan developed a power index with numbers for 5s 1 min, 5 min, and functional threshold power (60 min) to reflect neuromuscular power aerobic capacity, maximal oxygen uptake (V02max) and lactate threshold (LT). The index The numbers equivalent to an FTP of four w/kg are:

5s1 min5 min60 min
17x bodyweight 8.3x bodyweight 4.7x bodyweight 4x bodyweight
Andy Coggan Power Index

For a weight of 82.5kg, that works out to:

5s1 min5 min60 min
Power index at 82.5kg bodyweight

The 6-second sprint test

The 6-second sprint test is used by both the UCI World Cycling Centre to assess if a rider is more suited to sprint or endurance events and by the Janan Institute of Keirin as an entry exam.

The results of the test will give you an idea of your peak power and cadence. To perform the test, you ride as hard as possible for 6 seconds. You will get two figures, peak power over the single pedal revolution usually reaching in the first few pedal strokes and an average over the 6 seconds. 

You will recover from the test quickly and so the 6-second sprint can be performed fairly regularly before a normal workout.