My family this summer wants to do a 1/2 day white water rafting when we are in the Glenwood Springs area. We have never done one. My concern is I have back pain problems from herniated discs. When you get to the fun parts of rafting where you are in turbulent water do you feel the pounding on the bottom of the raft? I am asking this question for those who have actually done these trips and not from the actual companies who might have a bias in their response.