Better man than me. I've packed a young bull and three large cows out in three trips. But was so sore after the last one, I did 5 trips on the last cow. One trip with my gear and the backstraps and loose meat. And a quarter on each of the last four trips. Steep off trail downhill though but at least I didn't live on Advil for a week. That was last year when I was 69.
You're still doing good