Great question!

As a bigger guy myself, I find that pants with 4-way stretch are really helpful on the trail. They are comfortable, which is the most important, but they also give a bit for those technical sections of trail that require a bit more flexibility out of me (and my pants). In terms of winter, I find that soft-shell fabric is my favorite as it isn't too hot, breathes well, and provides really decent water repellency for light rain and snow. Here are a couple of options for you to check out:

The REI Co-op Activator and KUHL Silencr pants are made with soft shell fabric, the KUHL Disruptr are much lighter and breathable. You'll want to keep that in mind if you're concerned about being too hot, or potentially buying a pant that you can use year round. All of these pants come with a gusseted crotch and four-way/360° stretch.

Hopefully this helps, thanks!

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