older dog whining/barking in middle of the night

Question
We have an 18-pound, 11-year-old Australian Terrier.  He has always slept in
a crate in our living room and often goes there on his own.  For years, he has
been quiet in the crate until we are up in the morning -- usually around 7
am.  The past two nights he has woken up several times in the night (2 am, 4
am, 5:30 am).  He whines and has even barked, which he never does in the
house.  We have gotten up and let him out; he has peed and pooped and then
seemed full of energy and ready to play, but at our command he went back in
his crate.  A few hours later, the same thing happens again -- more whining,
escalating to barking if we ignore him.  He otherwise seems healthy, full of
energy, eating and drinking normally.  We have tried giving him extra
exercise and not letting him sleep as much during the day, but it hasn't
seemed to make a difference.  Do you think this sudden change in his
sleeping habit merits medical attention?  If not, how do you suggest we
handle it?  Any advice would be gretly appreciated, as we are rapidly getting
exhausted!

Answer
Something has changed, and you can't train a dog out of a physical problem.  Perhaps before hauling him off to the vet, look around the house and neighborhood for something that may be setting him off.  We recently reset the timer for our coffee maker.  Now we can sleep until the alarm goes off rather than the Lab.