Trainer Questions

        It's that time of year again were I end up spending most of my
bike time on the trainer. This year, as is every year I end up with
two issues.

1) Although my effort feels similar to road riding, based purely on
percieved effort and leg fatigue over time, my HR is considerably
lower during the rides at the same cadence. Cranking up the HR to more
closely match what occurs in a real ride via resistance causes me to
wear out early. I would assume this is caused by the trainer actually
causing higher resistance than real world. I have a couple of options
and was wonder what would be the better approach.
        a) Ride shorter at same HR and cadence
        b) ride long at higher cadence lower resistance same HR
        c) Ride long at lower HR, Same cadence 

        Any thoughts?

2) Yea old Numb nuts. I've gone on 4-6 hour rides on the road without
issue, yet 45 minutes on the trainer and apparently all blood flow is
cut off. I'm on the same bike, by all measurements I can see, in the
same position, yet the only time I have the problem is on the trainer.

Anybody else run into this?

~Matt