I've experienced debilitating back pain after yoga. I think because it doesn't feel like exercise it's easier to push my body past where it belongs.
265lb deadlifts? Yeah it's easier to listen when my back says "not today cupcake"
I don't want to sound like a hack groupie as I've mentioned this guy before, but doing Cameron Shayne's "Budokon for Beginners" (Budokon is a mix of yoga and martial arts) gives me a really good workout and has been great for my back.
https://www.amazon.com/Cameron-Shayne-Budokon-Beginners/dp/B00068RZ18/ref=sr_1_2?ie=UTF8&qid=1497965908&sr=8-2&keywords=budokon+yogaA potentially easier flow is "Yoga for Inflexible People". It is much less intensive than Budokon yoga, but for me, is harder (and better for training) on the balance side of things. The stretching portions are very easy though, and I think it would be difficult to injure yourself on them. The narrator is a little annoying. The DVD has a ton of exercise regimes that target different forms.
https://www.amazon.com/Bodywisdom-Media-Yoga-Inflexible-People/dp/B0002CZTOI/ref=sr_1_5?ie=UTF8&qid=1497966497&sr=8-5&keywords=yoga+for+inflexible+people+dvd(This seems to be an older version. There's another one with a different cover for 1/3 of the price)
Anyway, this week I'm realizing how much yoga helps my back. It's an incredibly hot record breaking heatwave mixed with increasingly crappy air, so I have been pretty much a couch potato and computer chair potato the last several days, and I'm already feeling it in my back. I was actually thinking I have to get the "inflexible" DVD out, as it's more like stretching and doesn't get me into a sweat. But the point is, for my body at least, is that for the yoga (or stretching or whatever) to work, I have to keep it up. If I don't, and then get into bad habits like sitting a lot, I can feel it in my back within a week.