Maybe I can answer this.
I have always used cardio for fitness. I hike on the weekends, which is where I test myself. During the week I would walk briskly, jog and/or ride my bike to work (9 miles one way).
These days I do a strength building barbell program (Starting Strength) 2x a week and sprint 1x a week. I take a comfortable, non-sweaty walk during lunch when I'm not doing the lifting or sprints.
Weekend hikes feel just as easy or easier than they've ever felt. I'm usually pretty exhausted and sore from the lifting but my cardio is still good, I can keep up, I don't feel like the effort is any worse. A couple weekends ago we loaded a lot of extra water and hiked up a steep firebreak to the top of a mountain to spend the night. Then we did trail work all afternoon and the next morning. I felt stronger than I have ever felt before. I had better stamina, I could do more trail work, even in the hot sun, without getting tired. We're going to do it again and spend 2 nights up there and I'm thinking what the heck, I think I can haul several gallons of water (in addition to my backpacking gear) up that steep firebreak no problem.
Female, 5'3", 49, Starting weight: 163lbs. Current weight: 135 (more or less).
Starting squat: 45lbs. Current squat: 157.5 x 2