I have scoliosis and weak sacroiliac joints. (That's where the pelvic girdle and the spine come together, more or less). I also have a sedentary job and hobbies. Several years ago, my back got so bad that standing in front of the stove long enough to scramble an egg had become excruciating. I was on the verge of giving my my house and yard to move into a condo. But first, I talked my doctor into sending me to physical therapy. PT saved my lifestyle, if not my life.
But PT wasn't much help when it came to yard work. Following the mower around the lawn had become exhausting. Then my daughter picked me for her power walking partner and that area of my life improved as well.
Then the weather turned crappy. Daughter and I joined a yoga studio as a replacement to walking. That was the best thing I ever did for myself (and her! She has scoliosis, too, only worse.) It is a year later and we both still go, still enjoy, still like yoga.
It helps that most of the yoga classes at this studio are drop-in. With our membership, we can go to all the classes we want, and not just yoga. I have been to the Yoga Basics, Core Yoga, and Restorative Yoga classes. Last year I started out going two or three times a week, slacked off to once a week during the summer, and now am building back up to two or three.
Yoga has improved my overall strength and flexibility without (much) soreness; the deep breathing prevents the build up of lactic acid in the muscles. It's never boring or repetitious. And since it requires a certain amount of concentration, for that one hour, the rest of the world disappears from my consciousness.
I haven't lost any weight doing yoga (because of that eating thing), but I definitely feel better. Gardening and housework are easier (not that I do much of the latter) and I have more stamina.
There are forms of yoga that are aerobic, but I haven't tried them for fear of collapsing in a sobbing heap halfway through the class, so I still need to do something to tax my heart and respiratory system. I toy with this idea, but I'm not much of a runner.
Others have noticed my improved posture and energy and vibe. I even inspired a couple of my friends to take up yoga themselves. I hope their experience duplicates mine. I can't imagine not doing it. (Famous last words!)