I did this run last night, and it went really well. I set off in an excellent mood, because the sun was shining for the first time in days (I am not liking the lack of summer this year AT ALL). I felt really positive throughout, and was still smiling by the end. Strangely, I found the 3 minute runs easier than the 90 second ones. I think it's because you have more time to find a rhythm for your breathing, etc. I'm definitely finding the breathing side of things more of a challenge than the leg-moving part at the moment. Hopefully my cardiovascular system will start improving over the next couple of weeks.
I usually run on Tuesdays, Thursdays and at the weekend, but I'm now a day behind due to a terrible night's sleep on Monday which meant napping instead of running after work on Tuesday, so I'll probably have to do run 3 tonight. I know that rest days are important, but I think I'll have to make an exception this time, especially as my legs are doing okay. I can't do run 3 tomorrow as Friday = pub night :o)