Well, I have been running the Couch25k program, and am now on W5D1. I'm 60. So far I have had no real issues beyond aching leg muscles, although a good stretch seems to mitigate that. I do remember the trouble I had tackling just 60 seconds in the beginning and already it feels like I have come a long way, I seem to have more energy, I sleep better and the general feeling of well being is fantastic. I look forward to my early morning runs every day.
I do have a question though: does anyone else get 'clicking knees'? I find that every so often when I walk now I get a 'click' when I bend my leg. It's new, and the frequency seems to have lessened as I go through the program. It isn't painful. I am guessing it might just be my age, and my legs adjusting to being used in a way that they have not been in a long time. Has anyone else experienced this, and does it go away completely after a while?