10h/week of moderate exercise should be straight forward. moderate exercise includes stuff like cleaning and other chores, playing with your kids, walking to the corner store, et cetera.
The study specifically includes walking in their list of exercises. You probably do want a mix of exercises -- 90 minutes of vigorous exercise a week is a standard recommendation, but 10h a week of vigorous exercise is probably contraindicated for the average 57 year old in the study.
Walking is good exercise for anybody who is out of shape.