I'm doing an abbreviated version of base training by condensing mid- and late-base phases as mentioned in Thomas Chapple's Base Training for Cyclists. I've done plenty of high-intensity rides (both short and long) earlier this year and am giving my body a break with some (late) base training before returning to higher-intensity riding. I plan to move into advanced training in 4 weeks, which will be 9 weeks before my first event this year. My current weakness seems to be muscle endurance as I was unable to keep pace with my group at the end of long (50-60 mile) rides. Granted, they had many more base miles and years of riding during retirement while I was still working, and I was trying to keep up with them too much, too soon.

So, in 4 weeks I'll begin advanced training. After doing lots of reading, to save my sanity I've decided to combine the elements of both Century training routines (non-fast + fast century) from Joe Friel's Cycling Past 50. It just so happens that his schedule includes elements on M/W that match those of our M/W group rides. My plan is to follow his schedule for the non-fast century (rest days on Friday and Sunday), but include a couple of elements from his fast-century training schedule: a tempo ride on Mondays for 4-6 weeks (on a spin bike - more control than with the group ride), then begin cruise intervals on Monday. I've chosen to do these on Monday so I will be rested for the hilly group ride on Wednesday. The schedule includes a recovery week. I want to incorporate a little of the fast-century training to improve my pace as well as my endurance.

Here's where I get confused:
Friel's training schedule for a fast century includes a 60- to 90-min cruise interval workout early in the week, and a long weekly (Saturday) tempo ride in Z2-4 if riding with a group, and Z3 if riding alone. However, his description of tempo rides (pg. 68 of this book if you have it) recommends doing tempo rides for 4-8 weeks before progressing to cruise intervals, and to avoid Z3 after 4-8 weeks of this phase. To me, this implies that tempo rides are phased out when cruise intervals begin and don't need to continue thereafter and not in Z3. Does he actually mean they can continue but don't need to, and should continue in Z4 instead???

The book was published in 1998, so his current recommendations may be different.