My brothers wife

My brother died a few months ago from a heart attack leaving his Widow to fend for herself. She is close to my age, maybe a few years older, but not much, but she smokes like a chimney.

Today I am going on a hike into the back woods with my dog and was considering calling her, but not sure she could make the journey, I know exercise is hard for a smoker. What if I get her going on the idea and then she bails halfway through the hike or something, or maybe she dies on the trail or something, that would be awful. Maybe I shouldn't call her. What do you think?