Should I do it again.......?

I haven't posted on here since I did the Great North Run, which is coming up to a year ago now. Since then, for various reasons, my exercise levels have diminished pretty quickly. Firstly I end up being too tired to head to the gym due to the drive home from work, which leads me to cancel my gym membership, when ends up meaning I end up doing very little.............but surprisingly, I haven't put on that much weight, so I don't feel that guilty. Plus I save £50 a month - bonus!

And then I get an e-mail from the good people at Bupa, telling me about their brand new event - the Great Birmingham Run (a re-christened version of the Birmingham Half Marathon). I get tempted to enter...........after all, I have done a half marathon the past two years in a row..............but my knees are knackered. Better to be sensible and not do the run.

And then I see a friend's Twitter feed..........and his speed and distance has improved to better than I've ever managed.......and I'm jealous of his amazing achievements already........so I get tempted to start running again.........the big question is should I do it again?!