Thanks so much for this detailed and informative answer, Kristy. It was a very kind response. My issue with walking is that I get a headache after even a walk around my apartment. I stop walking when I feel a headache starting to prevent it from getting worse. I know from experience that walking longer distances, like around the block, will cause a severe, debilitating headache which sets my recovery back by weeks. I am weaning off prednisone now, which seems to have made my headaches come on faster and to additional stimuli, such as listening to podcasts for more than 15 minutes. I will check out the link you provided on this - this is new information to me.
Thanks again,
Joe