With temperatures in the -20s, we only take our sheltie (Theo, ~1.5 yrs old) out twice a day to do his business. We haven't gone on walks this week because the neighborhood sidewalks are very badly shoveled and there's ice. Every time we take Theo out, he doesn't want to come in (even after doing his business)) and starts behaving badly (like jumping on my mom). What kinds of exercise are best for shelties in the winter?