I want to break into song. “Bring me sunshine in your smile . . . ” We look like Morecambe and Wise, as we glide along, leaning forward, making exaggerated arm swings as we slide with alternate feet. I am practising cross-country skiing without the skis.

I once attempted cross-country skiing in France. Today, I am not in a serene vallée but grey London. We are practising on grass that is covered not with snow but dog poo. At least our tribute act seems to work: soon the sun shines through Hyde Park’s autumnal trees as geese fly in to land on the Serpentine.