Posture in our culture is a funny thing. We are often taught to stand with poor posture.
I suggest the doctor check, this is always worth while before adding anything to your practice. and then as other have suggested yoga which is good, I also suggest Taijiquan. Gramie does yoga and I do Taijiquan and Qigong. I will not suggest one of yoga and taijiquan are better, just different in the details but both work on similar things. Qigong can also be helpful. Qigong exercise tend to be short and specific for posture, and energy work.
Just a few thoughts
Good running and be Careful out there
Certified Chi Running and Chi Walking Instructor
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