Cycling Fitness / Training Advice

Alrighty,

The latter I feel is likeley to have a link to some lung damage via smoke inhalation I got when I was 3ish.

I was given inhalers and referred to the hospital when I was 8-9 if I remember right, but I never went and I never used them!

Ive always managed 'alright' so never bothered to look into it again.

I would seriously go to your GP and have your lungs checked out properly before you start murdering yourself with interval training. I used to run cross country and ran the training program for my college. One year, we took a bunch of newbs out to do the dreaded three minute runs - eight sets of run as hard as you can for three mins, no holds barred - and on the seventh one kid started coughing up blood. He'd had some kind of lung damage he'd neglected to tell me about. He was fine after a week or so, but I'm sure it didn't do him any good to make his lungs bleed.