It's may be just me or that I started training hard at 50, but I've found Friel's plans to be a bit optimistic. They are also excellent and will get you flying on the bike. Which I think is fun. But be careful not to overtrain. It's hard to emphasize that enough to someone who has not yet experienced it. When you get your HRM, start taking and recording your morning resting heart rate (MRHR). My system is to get up, pee and get dressed. Then lie down for 5 minutes while watching your HR. Write down the lowest steady HR. Your MRHR should drop overall as the program progresses, but you will also notice that it's elevated after a workout. That's normal. But if it jumps up 6-8 beats and stays there for a couple of days, you must take easy days until it drops back down. This can be frustrating, but it's necessary.

This type of program is designed to push you to the edge. That's the reason they're so effective. Your job as your own personal trainer is to make sure you don't go over that edge.

I found that I enjoy a modification of Friel's program. I purchased a recording HRM. I think the closest thing to it now is a Polar 800CS. It downloads into my computer, and the software that comes with it will show time in zone by the day or by the week. So looking at it by the week, the way Friel does, I attempt to adjust my weekly zone totals to about equal what he calls for. Which means I can do any sort of ride I want, just as long as I observe the zonal structure of that week, sort of do the hard stuff in a way that approximates intervals, and spread it out reasonably in the week. Which means that I can do rides of any length, as long as the times add up correctly. You shouldn't have much trouble doing this where you live.

It's very hard, but necessary to do as Eric suggests with the moderate and easy rides. Another option is to do those rides indoors on rollers (preferably) or a trainer. The long cruise intervals can also be done on hills, I feel. It's not quite the same, but close enough for the non-racer. The 5 X 12 structure can also be interpreted as an hour at LT, which you can do by putting together a series of long climbs or hill repeats.