Well I went out today and did my own thing! I did the 5minute walk, then I jogged for 5 and then walked for 2, repeating this for about 28 minutes. The object of today was to try and land on my feet properly, not striking my heels, as I don't want a repeat of the awful back pain of last week. It got better as I went round, plus with my hands palms up as suggested by a fellow C25Ker, it wasn't too bad in spite of the challenge of running into the wind. I've had some really helpful replies about posture, including running like an assassin which made me smile! Thanks to everyone for their help. I'm going to put the new tips in place on Thursday, so I'll let you know how I get on.