Use it or lose it

I got a little shock about a week ago, when my physical therapist (whom I like a lot) gave me my walking papers and said I should proceed on my own with the exercises he'd given me. "I'll continue to improve, right?" I asked, since I'm still in a lot of pain at night from several herniated disks, and I haven't returned full tilt to yoga. "Yes," he said, "but you really need to adjust  your expectations and focus on maintaining rather than progressing. After all, you're well ahead of other people your age in terms of what you can still do." What! Are they even allowed to say such discouraging things?

His well-meaning comment cast a pall over my week. Would I never be able to do, say, the peacock? Or the turtle? Or any of the other poses that keep me up at night figuring out how precisely to approach them? I know yoga is not about the physical practice. But the physical practice provides some wonderful thrills, and I'd hate to forgo them. 

Then I read two very encouraging pieces of research: one from the journal Skeletal Radiology, suggesting that for runners, "continuous exercise is protective, rather than destructive" to knees; and the other from the New England Journal of Medicine, suggesting that weight training, once thought to trigger lymphedema in breast-cancer patients who had had lymphedectomies or radiation, actually helps prevent lymphedema. 

These studies aren't precisely at odds with my PT's comment, but they threw me into a much better frame of mind, one that allowed me to return to yoga feeling I was engaged in a healing practice rather than a pointless one.