I've just started training seriously again after a couple of months off. So far I've done three 5 milers to break myself in gently. Anyway after each one when I've got home again I've had a coughing fit and brought up some phlegm speckled with black dirt.
I seem to remember this happened the last time I started training seriously - it must be dirt that is permanently resident in your lungs unless you exhert yourself sufficiently to dislodge it.
Does anybody else get this after a lay-off ?