Lee has only had a small injury in his foot that made it difficult to put a lot of pressure on his foot.
I don't know how much he was incapacitated, but he has been walking around normally and I imagine he would have been able to do many activities that don't involve a lot of weight bearing - exercise bike, rowing machine, some weights.
He is trying to save his career, so he might have been doing all he can and be in the shape of his life apart from not being able to actually run.
I don't think he would have been sitting around and be starting from scratch now. I think he'll be as fit as he can be, and since he has been able to use a wide range of equipment, he should be in good nick.