I have a friend who is really fit. He retired young, and spends his free time trail riding and hiking. We just went on an 8 day backpack trip, and he (of course) kicked my ass, basically running up 2,000 feet while I slowly worked my way up. I was worried that he wouldn't invite me out again, because I was so slow. But we had a large group zoom call last night, and I got to witness him saying "No, seriously, there is something really weird about [My Name]. No matter how much climbing we did, she was never sore the next day, and she kept wanting to do more. I had to rest for a week after we got back from the trip, she exhausted me". Now, I know it is far easier to go slow rather than quick, which is why he was tired, but it still made me feel good. And he has offered to take me out again in a month! This time just for four days, and an easier area, but I'm really excited to go out again!