that is intense. how do you feel after you do it?
Sweet. 12% at that pace is smokin'. No holding on?
No holding on except sometimes when I took a swig from my water bottle I had to grab on for a second or two.
I felt pretty good afterwards. My heartrate never got real high - only in the 130s - and was down to normal pretty quickly. One thing that will make a difference will be to start wearing a pack and build up how much weight is in it.
Some mountain in Africa has no idea what's headed her/his/its way. Check out the calories you're burning per hour at the 12% incline.