I've been following Couch25K for quite a while, and find that when I get up to 20 or 25 mins I tend to get sick with cold, chest infection, holiday (!) and have to stop for while ( I have asthma which kicks in with a vengence). I was ill most of December (two lots of anitbiotics, steriods), when I was up to running for 20 mins. Just got back to it, and started again on wk3, which seems quite easy. How far back should I go when I start again? A week for every two missed maybe?