Bike Trainer Speed Workout 3

This is the 3rd in a series of 6 bike trainer speed workouts. This workout is similar to a tempo run - but on the bike. It is supposed to be done close to the Functional Threshold Power zone (FTP) or at the same pace as a 40k Time Trial. At this pace, should also be the anaerobic threshold, where you are (just barely) not taking in enough oxygen to meet body requirements. Lactic acid accumulates in the muscles and they become fatigued. Eventually, at this pace, an athlete is unable to continue.
Unfortunately, I don't have a power meter, so I am estimating my effort by 1) percieved exertion 2) Heart rate monitor.
I estimate that my Functional Threshold Power (FTP) zone is at about 162BPM (plus or minus). So I tried to keep my HR within about 5BPM of 162. Unfortunately, I was just a little on the low side, but it was still a real tough workout.

1. 7 minutes easy spinning - warmup
2. 8 minutes in saddle @ FTP - 150BPM (Now 15 min mark)
3. 2 minutes out of saddle @ FTP - 165BPM
4. 8 minutes in saddle @ FTP - 154BPM (Now 25 min mark)
5. 2 minutes out of saddle @ FTP - 170BPM
6. 8 minutes in saddle @ FTP - 159BPM (Now 35 min mark)
7. 2 minutes out of saddle @ FTP - 172BPM
8. 8 minutes in saddle @ FTP - 165BPM (Now 45 min mark)
9. 2 minutes out of saddle @ FTP - 175BPM
10. 1 minute in saddle @ FTP - 170BPM (Now 48 min mark)
11. 12 minutes easy spinning - cool down

That makes for 1 hour total ride time. 41 minutes were @ my estimated Functional Threshold Power (FTP). Stay tuned for workouts 4-6. Power Up. Weight Down!