Two ways to go he

Reduce the weight of each trip. Leave your garbage bin empty all
week, roll it down the hill empty, carry the bags down one at a time.
They can be as small as you want, you're the one filling them.

More controversial, reduce the total weight of your garbage. This may
depend on what recycling is available in your area. I lived in a
location where the allowable garbage pickup was one kitchen sized bin
(1 foot square, 3 feet high) every two weeks, and if it contained
anything recyclable (paper, aluminum, etc.) then it could be rejected
or you could be fined. We recycled everything possible and had no
trouble fitting our garbage into the bin. This was from a family of
four. It can be done with little effort once it is a habit.