For those of you who know about these things, my pre-run peak-flow measurement was 430, which is normal for me.
I went out and ran 43 minutes and covered 3 miles. There were a few stops in there, but I didn't count those in the time or distance. It was the longest time and the furthest that I've run. The air was much colder than I anticipated and I could feel it burning in my oesophagus for the first 10 minutes, but after that I was fine.
But (isn't there always a but?) 7 hours later and my peak-flow is 210 and I'm struggling. I'm making noises like a cow giving birth when I breathe in and a draughty barn door in a gale when I breathe out. If I use any more Ventolin I'll have too much of a tremour to handle a mug of Earl Grey!
I'm keeping my fingers crossed that my lungs will recover before work tomorrow.