But isn't Sweetspot a zone within levels 3 and 4?
In this article about the Sweetspot there is mention of a 'grey zone'.
http://www.nasvik.se/loadeffect.pdf "increasing the intensity, such that ~103-108% of FTP is something of a grey zone, and the relative efficacy of ~10 minute intervals seems questionable."
Like it or not, people do train in zones. Doing 2x 20 minutes of Sweetspot is training in a zone.
But to be serious for a moment, is Dr Coggan pointing out that there is no magic zone or level in which or at which one should do all their training? Proper training or effective training requires work at numerous levels and a good effective training session will just as likely drift and meander through many levels or zones as be strictly confined to a narrow range of percentages of FTP.
No one is suggesting someone do nothing but sweetspot . Although I do think some recommend it as a good workout if all you have time for is an hours training.
I think some people assume that because the use of a power meter enables one to train within specific levels or zones with considerable accuracy that this is the very purpose of power meter use. They erroneously assume that just because they are training at a specific level they are training more effectively. Others assume that because they use a power meter and track their training and are using software to analyse their training they are training better and more effectively when all they are doing is documenting their own incompetence.
You can't blame Dr Coggan for power meter users incompetence or for the use of training zones. People have been in the habit of training in zones with heart rate for decades before power meters.
Riding outdoors it is almost impossible to stick to specific zones or levels anyway, yet some people seem to believe there is some magic physiological training benefit to be derived from developing the skill to ride for hours never drifting out of a specific training level.
If a coach tells someone to ride for a certain time at a particular wattage does it make any difference if you call it a level or a zone?
I notice the workouts shown in Training & Racing With A Power Meter give ranges of % FTP i.e. 91% to 105%.
Now surely that is a zone and the book is encouraging someone to train in that zone or at that level for a suggested number of minutes. e.g. 5 minutes VO2 Max 106% to 120% FTP.
I can't see any real difference between a power level and a zone. Does the word zone encourage people to train differently to the word level?