When the going gets tough... ...the tough go running in icebugs
I've done a few 10k runs and some 1k repeats indoors on the treadmill at the gym, but for the long-slow-distance type of runs it's really much nicer to go outside. These shoes with spikes (Icebug ATTLA) provide added grip on harder snow and ice surfaces, although they are pretty slippery on an indoor stone floor. They are warm and waterproof although towards the end of today's 14k it felt a bit like running in rubber boots (there is a trade-off between waterproof and breathability I guess).
Running in loose snow is a bit like running in loose sand on the beach. You spend a lot of effort and go almost nowhere! Today's pace was a minute or more slower per km than usual.