back ache

Hi all , i have recently started doing one hour duration turbo workouts , Chris carmichaels, i have decided that i will stick with a dicipline for about four to five weeks then move one. I have started with the time trial, apart from the tiredness from training i also seem to be getting a sore back , lower to upper, this never happended before on the turbo. Do you think it is possible that it is due to the high tension that is created in the workout on the body overall, because to be honest i do not feel stretched on the bike or uncomfotable. I used to compete at national leval in Judo and even after training for a good few years at it i always got an all over body soreness in places that i did not normally get from training after a comp. At the moment it is not interfering with daily life so i know it is not an injury due to incorrect postion, but i was wondering if it is something others have experianced. Thanks .