I don't believe that you're out of shape. Maybe you aren't in the shape that you'd like to be in but not out of shape.

We finally got out of our backyard and did a portion of Indian Creek yesterday. It kicked my butt both aerobically and technically. When I got home, I discovered that Indian Creek is considered advanced.

Now I have something to compare Ridgeline too. I'd call Ridgeline mostly easy with a few moderately technical sections. I don't think that any of the extended climbs are much more than about 1/2 mile but there are some pretty steep sections on some of the climbs. It will take us about 2 hours to ride most of the trails and that includes frequent, short, breaks to rest and regroup. I'll have to take a few breaks before and/or after some of the steep sections and there is a technical switchback that I won't ride yet. I'm hoping that you and Solo don't get bored waiting for me