Yoga is so much more than physical practice or sports – breath, meditation and philosophy are a fixed part of a yoga practice.
Nevertheless, as already written in the Yoga Sutras, the full potential of yoga unfolds from the physical to the subtle (inner work). With back pain, shortening and tension in your body, it is quite difficult to concentrate on subtle breathing, to meditate with a calm mind and to develope a relaxed sense of body- and self-awareness.
Therefore, a healthy physical personalized yoga practice is just as key to level up in your practice as more subtle techniques.