From a muscular perspective, snowshoeing is very similar to running. On flatter terrain with hard-packed conditions, your run gait can remain intact, perhaps with a few small adjustments. The ground contact time may be a bit longer in snow vs running shoes, like running in softer, sandier conditions but your body adapts and adjusts to that quickly. The larger muscle groups that are activated when you run.
20 minutes easy snowshoe running/hiking to the base of an appropriate length hill 10 x (30 seconds strong/fast uphill snowshoe run, 2 minutes easy recovery walk/jog back down the starting point)
15 minutes easy The work-to-rest ratio on this set is large on purpose. The total workload is only five minutes but if you do these hard enough you will be glad when they are finished. You should make it to a similar spot up the hill with each interval. This workout is easy to scale. If you are not ready for 10 of these, simply cut it in half or any fraction thereof.