Mind versus body

Yesterday I pushed hard for my 30 minutes run because I was unhappy with the effort I put out Tuesday morning on my hills training. After I started worrying about today's run, will I be too tired to do my "Ladder" workout, did I make a mistake by pushing too hard on an easy day. So today I went out for my morning run, weather was really warm, around 0C with 20km/h or so wind. Only problem was that it was raining a bit, so the usual snow on the street was now ice, and I was kinda nervous after my wonderful fall two days ago. Anyway I went out and the program was calling for 15 minutes in zone 1, 15 minutes in zone 2, 10 minutes in zone and then 5 minutes back in zone 1. For those entire 15 minutes of zone one running I kept thinking that I made a mistake yesterday and that I would be way too tired to push the pace enough to reach zone 3 for 10 minutes. I was even scared that pushing 15 minutes in zone 2 would be a real challenge. So I spent 15 minutes thinking that maybe I should switch for another workout, just do an easy 45 minutes run instead since I pushed zone 2-3 yesterday anyway. At some point my mind almost won the challenge, I was running at a pace of 6:30/km or so and I was convinced that my body couldn't handle ,uch faster today. Then the 305 started ringing telling me that I had to switch to zone 2, that I had to push the pace at least 1 minute faster per kilometer. At that point I decided to give it a go, to push harder and to try to reach and stay in zone 2 for 15 minutes. I had no problem, went from 6:30/km to 5:15/km or so, I was able to keep the pace even if my mind was convinced that I couldn't. Even there I still thought that zone 3 would be impossible to handle for 10 minutes, I knew I would have to run faster than 5:00/km to reach and stay in zone 3 and I know it starts to be painful at that speed. My mind was tricking me and trying to convince me that I couldn't handle it. That I should slow down and relax a little bit, that my legs were tired. But I just decided to ignore it and I ran that 10 minutes in zone 3 without any problem. Then I finished my ladder with a 5 minutes trying to get back down into zone 1. It made me realize how much our mind and our body are two different entities. Even if I was sure that I couldn't handle it was almost easy, I could have swear that there was no way I would be able to run fast today, but I did. So now I wonder, all that training that we do, is it mainly to train our body, or our mind? Is those long training day, are mainly to get our mind used to the fact that we will suffer and that we have to keep at it? Today’s training Running Distance - 8.75 km Time - 53:00