Back pain

Things happen for a reason is my take on life.  Last nights training session was called off and I was pleased as I felt tired.  Later on in the evening my lower back started to go into spasm which was uncomfortable but not sore.  It just made me think before moving.  When I woke this morning it was slighly better but still "there" so I am going to skip the running session tonight to make sure I am fit enough for the weekends big cycle.  Disappointed as I wanted to try out my new technology (my Garmin 310 watch/computer) but that can wait - always listen to the feedback from your body.
I hope I can manage a swim tomorrow morning but it will depend on how I feel in the morning.