I've thought about picking fencing back up. That would be a lot more exciting than walking! However, it's a time commitment. At the moment I'm pretty busy, so it's hard for me to put things on a schedule, where I can walk whenever I can fit it in.
Not doing any mobility work, but I have in the past to help with squat and deadlift technique. Supplements:
-Whey + Creatine
-Jack3d + BCAA (when training fasted)