My baby is 9 months and almost 25 lbs / 11 kg. We use an Ergo, and I carry him whenever I go out in the city, which is about 3-4x / week. This usually involves travelling through the city, visiting friends, going to our baby group, and doing errands, etc....a lot of walking. Plus regular trips to the grocery store, also a 15 minute walk. I also try to wear him on my back when I cook, but lately he's not having any of that. It somehow doesn't feel right to wear him on my back through the city....I would feel more connected to him in the stroller, where we could see each other.
Anyway, he's getting heavy and I find either my back, my shins or legs, or my shoulders start getting strained. Especially when I go grocery shopping and have equal loads front and back (carrying groceries in a backpack) it's rough.
So, just wondering at what age or weight did you start using the stroller more. I can predict we'll start using it way more in a few more months, when he's about one year old. I'm curious what others have done, and if you wore / wear your baby regularly past age one or so, how does your body hold up??!!