OW, dammit!
    
Superstition always bites.  Last week I was 
cheerfully nattering about beneficial exercise after a month of rejuvenating the back yard.  
Yesterday, while breaking up some roots, my lower back announced it was TIME TO STOP.  
It's a familiar pain.  Happens about twice a year since 1975, when I snapped a tendon or something while lifting a heavy object at work.  Most of the time it starts without any obvious cause, presumably from stress or bad posture.  At least this time I know why it happened.  Typically it fades in a week if I stay loose and walk a lot.
However: the newly planted clover is starting to pop its little heads through the soil!  Makes the pain worthwhile.  Almost.