Critical periods, such as the forcing of a break-away or a final sprint, are often decisive in a cycling race. It is therefore important to know how you perform on these critical periods and how these performances relate to the performance of competitors.Yes, it's another power profile test but this test takes as much effort as any other test, it's free, and it gives you the information that is missing from other test protocols, that is, performance in 8 different critical periods in racing and using aerodynamic drag it differentiates between the climbing and time trial qualities of a rider.Plus - I have made an audio version of the test - why audio? - There are some intervals that should not be capped by power prescription - it’s kind of like erg mode on a trainer - it might be holding you back.Find more cycling podcasts at semiprocycling.com.