I didn't say zones based on HRMax won't work. I said there is "no way to know if one has improved fitness." Zones based on HRMax are certainly better than nothing and in many cases will get you in the ballpark. In your case it is a tool to keep you from going too hard during recovery rides and as such it is probably a very good tool for you.

I am saying however, that you can't measure increases in fitness with a zone system based on something like HRMax which never changes. A better way to measure fitness for cycling is lactic threshold based zones. LT is what allows you to go faster and further - fitness - and it can change a lot as fitness improves.

LT based zones may or may not apply to other sports. Running is a perfect example. I have no idea who Eddie Fletcher is or what sports he coaches. I could throw out names like Dr. Edmund Burke and others who clearly see zones based on LT as superior to zones based on HRMax for cycling.

Zones based on %LT for cycling is widely accepted as superior to HRMax zones for cycling. This isn't something I made up.


-Tim-