This depends on the reason for your back pain. If you speak to most spinal surgeons they will suggest one or the other. Generally, if something isn’t hurting your back or causing your pain that is a good place to start. If you have been doing group classes try some 1:1s to make sure you are moving correctly. Otherwise, if you are unsure then go and see a Physiotherapist who will give you a full assessment and can point you in the right direction.