Originally Posted by ericgu
I'm going to voice a dissenting opinion...
You don't need more work at LT threshold or above, you need more work on basic aerobic fitness. Here's how I think of it:
The amount of effort that you can put out for an extended amount of time is your aerobic base. You develop the aerobic base by lots of riding below your lactate threshold - quite a bit in fact. Carmichael's approach sets 85% (83% if you're older) of your 3-mile field test average, which is pretty low. I think Friel's approach will end up with a similar range through a different approach.
Long slow distance and "junk miles" are an old school appproach for those who either don't understand the physiological adaptions taking place at various levels of intensity, or they are racers who need to handle 4+ hour races, or other people who care most about very long rides. The main benefit of such long rides has more to do with adapting the body to sitting in the saddle for so long and less to do with improving performance at intensities one might need for rides/races of under 3-4 hours.
Friel wrote a book with some good stuff in it, but he has some serious catching up to do with regard to training physiological adaptions, and nutrition. Some of what he discusses is better understood by sports scientists, sports science-based coaches, and similar.
Originally Posted by ericgu
You want to base your ranges on where your lactate threshold is, but that differs based on your fitness.
No, the LTHR willl remain within a few bpm for an individual throughout the season, assuming they are not starting as a complete couch potato.
Originally Posted by ericgu
Having said all that, without a test, I'd guess that your overall average should be in the 120s, and you shouldn't spend much time above about 140 - not more than about 5% of the ride time.
I suggest you read the information here...
http://www.cyclingpeakssoftware.com/power411/levels.asp
Note in particular the information in Table 2 regarding the adaptions that take place at various levels of intensity. The number of checks in each category represent the effectiveness of training for various aspects of fitness. If you want to ride easy you can do that, but it will take you far longer to accomplish what you can by riding closer to threshold. You can ride for 3 hours a week in level 3 and 4 to get the benefits of riding for 10+ hours in level 1 or 2, and for the most part you will also get some benefits not found in level 1 and 2. So, do you have 20+ hours a week to train, or more like 6-12 hours?