Well, I have done it. Got out of the house just after 8 am and up the road to the gym (12 mins walk uphill so that counts as a warmup). New shoes on and onto the cross trainer to warm up again while starting up week 8 of Laura. Then onto the treadmill. All I could hear was my feet smacking on the belt, thump thump thump. Could barely hear Laura because of the loud music in the gym. 'Ran' at a snail's pace, tiny steps, feeling wobbly but didn't shoot off the end . I didn't much enjoy it but it was less awful that I had expected. Warmed down with 2 mins creep getting gradually slower on treadmill then onto the rowing machine for 2 mins easy rowing.
I'm not convinced that i will do longer runs on the 'mill, but I didn't mind the cross trainer. Might use that and redo some early c25K weeks, using slow speed for the walks and quicker for the runs. Think I could cope with that plus it will exercise different bits of me.
So I am planning on keeping up with parkrun every Saturday, the gym once a week and if I am free and it's sunny, a run outside as well.