Hi, I teach yoga and pilates and yogalates. I am also GP Exercise Referral trained and have just started my Level 4 Back Pain Exercise Specialist course. I actually teach all types of exercise classes though.
I think it’s difficult to answer this question for two reasons: both pilates and yoga classes vary greatly, depending on instructor and style of class; secondly, everyone is different so what one person find helps back pain, another may find this aggravates the issue.
I get a lot of back pain myself. I need to be careful not to overstretch when doing things like twists. In general, back pain aside, Yoga is harder on me and I particularly dislike sun salutations. Pilates can be uncomfortable though with some supine (lying on back) exercises.
I have had people come to my tai chi class after being referred by their physio due to back pain, so maybe that is another class to consider and that is the most gentle of all classes I teach. Again, it depends on type of Tai Chi and the instructor to some extent, as I know a colleague who apparently is very tough with Tai Chi! Whatever you choose, mention to your instructor before class.
My motto whatever class I teach is “listen to your body, do what works for you.” I always say to try not to worry about what anyone else is doing, you can make moves smaller or bigger to suit. A good instructor will usually be able to give alternatives.
You can do a 200 hours yoga teacher or a 500’hours one. I did my 200 first then my 300 to get my 500 hours and the 300 actually gave specific poses for back pain and other conditions so it may be worthwhile looking for a 500 hours teacher.
Back pain is a condition that Exercse Referral practitioners can work with, even without the Level 4 Back Pain course. You may also like to try aqua. Hope this helps