Have done this loop on previous trips with friends as a 3 day backpacking trip. During the last one I ran into two 60 year old women doing this as a single day hike. I was stunned, but it got me thinking, so I came back on August 9, 2018 and did the loop as a one day hike by myself. I did it clockwise with a light pack of about 10 pounds. It was a little warm and just a few sprinkles at sunset, but otherwise the weather and the trail were perfect. It did take me all day and I was pretty tired at the end, but felt good enough to drive the hour back to Glenwood Springs. I am in awe of the people who can run this loop. I will be 70 on my next birthday.