When we can’t do something, we start to appreciate it more. That quintessentially describes my last month of running. After the Philadelphia Marathon – the Sunday before Thanksgiving – I took a week off for recovery. Then, I got right back at it. I got new shoes. I sustained, what’s believed to be, Achilles tendinitis. I can nearly guarantee that the injury stemmed from tying my new shoes too tightly (it’s one of those injuries that comes from not knowing what the pain is, trying to run through it until it’s too late and becomes an actual problem; and that …