A Body in Motion  By Stacie Lynn Grossfeld, M.D.  Editor's Note:
In this issue we welcome Dr.Stacie Grossfield, M.D., and the
Body in Motion column. Dr. Grossfield is a four- time finisher
of the American Birkebeiner and a fourth place finisher in the
Korteloppet Cross Country Ski Marathon. At its best; cross
country skiing is a graceful, symmetric form of exercise. But
when the technique isn’t quite right, or we push training
sessions too hard too fast, our bodies revolt and break down.
 Dr. Grossfield will address the challenges faced by a body in
motions and answer your questions. Please send your thoughts and
questions to lou@crosscountryskier.com  I am a 43-year-old
female that skis the Birkie. This fall I started having knee
pain when I was hill bounding. I now have the same type of pain
with classic skiing while going up hills. I don’t remember a
traumatic event or injury that started causing my pain. What do
you think is causing my symptoms?  Patellofemoral pain syndrome,
also known as chrondromalacia