Join Date: Nov 2007
Location: Ontario, Canada
Because he has been out of work for so long, he has no topline muscle. I would suggest lunging him in side reins. Start them loose and as he starts to build up his muscle and carry himself (he will start to look for contact, and you will notice his neck and back flexing) then shorten them. If you are not comfortable using sidereins then don't.
When you lunge, do it for about 15 minutes, and then ride for no more than 20. Don't ask your horse to bring his nose in, ride him forward and ask him to carry himself using your lower ab muscles and asking with your inside leg to pick up his back end when the inside hind leg comes up (so in rising trot, when you go up squeeze with your inside calf).
After a few weeks of this, you should see some topline development.