Coach Smith here again.
Karen, Yes there are several articles refuting the first anti-exercise
article. In the first (poor) article, the babies were dropperfed the milk.
There has never been any evidence than babies don't like the milk from the
breast. (Unless she's sweating so hard that sweat runs down her breast into
the milk, maybe??)

Mothers all over the world exercise hard and breastfeed with no problem.
Including women whose daily life much physical exercise, such as women in
mountainous regions. Run all you want.  Wear a jogbra so you don't bounce -
that can be uncomfortable. And nurse before you run, of course. Your knees
are in more danger than your milk or your baby.

Post again if you need the references and I'll try to dig them up; or call
LLLI's Center for Breastfeeding Information.

Linda Smith, LC in private practice, Dayton OH