Nope, back injury.

I called it a day hike because we spent the night in the Little Yosemite Valley, then did the eight mile round trip to the top from there. It is 16 miles round trip to the top from Happy Isles on the valley floor. And uphill ever step of the way, going and coming.

Lots of people do it, or try, very ill prepared. One of the reasons the NPS has a couple of rangers living in tents near the Little Valley all summer long, to help those folks back to civilization...