Yoga - always a new age practice or when simply used for exercise simply exercise and stress relief?

Yesterday from the pulpit one of our officers denounced the use of yoga "because it is a new age practice," she said and because you empty your mind while practicing it. I'm wondering what's wrong with getting rid of the things from your day that caused you stress. I know of one incredibly strong Christian lady who has used Yoga before in a Christian context. As she was walking her students through the poses she asked them to breathe in certain scripture verses and breathe out impurities - perhaps it's mystic but our God is mysterious.

As long as I'm not adhering to another religion by doing yoga for daily exercise I think I'm in the clear. Besides that, I'm becoming quite flexible!

Tell me what you think. I probably won't stop doing yoga but I'm open to your thoughts.

Joy