Another thing I noticed while on holiday this summer was that I have lost the ability to cope with stairs.
In Beijing, I have always lived in apartment buildings, and have always used the stairs. But having to walk up five or six flights of steps to get home, while a decent dose of exercise, pales into insignificance beside having a split-floor living space. I rarely leave my apartment more than once or twice a day. If you live in a house or a two-floor apartment, you are going up and down stairs - even if only a single flight of them - dozens of times every day.
Moreover, Chinese stairs seem to have fairly shallow risers. I currently have 16 steps to a storey of barely 9ft. My old apartment had 19 steps - a double-flight! - to a storey of less than 10ft.
I suppose this works out to only a bit over 6" per step. I would guess that most steps in the UK or America are more like 8" or so high. It makes a big difference!
I find my creaky old knees just can't cope with going down a long flight of steps with tall risers these days. Particularly when my legs are extra stiff from a too-long run! And particularly when - as seemed to be the case in every house I stayed in this summer - the stairs have very narrow treads (less wide than they are tall!!), and are of bare wood (worn to perilous slipperiness), and tilt forwards slightly, and wind through sharp right-angled turns. I tell you, I would do my damnedest to limit my visits to the upstairs bathroom in these houses. And the experience made me feel like a very decrepit old man.
I fear my lack of experience with steps is another reason why I have lost so much resilience and flexibility in my calves (and strength in my knees and thighs) in recent years. Hence, I am trying to find silly little pretexts to go up and down the stairs in my building more often, cultivating unnecessary habits to increase the amount of this kind of exercise I am getting. One of my favourites is that every time I take a bag of rubbish out to the recycling bins in the courtyard, I force myself to climb to the top of my building's fire stairwell first. That's 15 storeys. And, since I only have very small rubbish bags at the moment, this is now pretty much a daily ritual.
I also have a pair of uncommonly steep Chinese steps (nearly 10") leading to my balcony, so I'm starting to do step exercises on those every day.
I don't know how much this will help my running. But I do hope that the next time I stay in a house, I won't view having to use the stairs with such trepidation.