Since there is motor involvement and if the cause is inflammation from an immune problem, its important to know that the therapists should be careful not to overwork you. Inflammatory immune is not treated the same as a structural problem. The "No pain, no gain" does not apply. I'm afraid with your endurance training background you may overextend which can be a detriment. I was overworked in rehab and it took many months to reverse the damage.
We had to measure the strength of my muscles every day. If I lost muscle strength we scaled back. I worked 10 minutes on and 10 off during the sessions and was very careful not to overwork any one muscle group. I could also gage by how tired I was after each session. If I slept more than the "benchmark" that was also an indicator to scale back and do more passive therapy. The most important thing is to keep your range of motion until they settle on a treatment plan that stops the progression. Passive therapy is very effective.

A pair of boots may help support your gait in the meantime so you don't trip and hurt yourself.