Burning those calories

I know the machines can be off with their calories burned count. However, this morning when I saw that I was in the 900's, I had to keep going to see what it would do if it hit 1,000. (My machine only shows 3 digits) . It started over at 0. lol I supposedly burned 1,011 calories. Unreal. It was a kick butt workout. I ran 6 miles, and then put the speed way down to 3.5 mph and the incline up to 12% and walked another mile. Hopefully my knees won't be hurting from that incline. With cool down, my total was 7.12 miles; 1,296 feet climbed. WOOHOOO.