First off I don't think its the positioning as I can sit in that position for 3-4 hours on a steady ride no problem, the problem comes when I give it the beans. It only seems to give me grief when I am putting the power down for an hour plus and the pain is either side of the spine in the lower back. Are there any back strengthening exercises that will help this. I did a reliability ride on Sunday and the power was down for 4 hours solid and I was in agony in the saddle.
Have alot of issues with my lower back at the moment. Best stretch I've found to relieve the tightness is to lie on my back legs bent, gently bring your left knee up to your right shoulder with your hands. This is a very deep stretch so do it slowly. If you find that is easy enough, when your knee is at your shoulder look to straighten your leg slowly.
Almost instant relief for me.
Get yourself to your nearest physio/osteo to talk you through the best exercises for your situation
almost certainly position contributing greatly IMO. the basic road bike position flattens your lumbar curve
Am not a medic/physio, best advice would be find one you trust and go through issues with them.
As far as my own experience goes, getting your 'core' really strong sorts most back issues.
Pilates and the right sort of yoga can seem a bit pointless, but if you do them right (and regularly) they really work. Surfing is also great (if you are near the coast)?
Maybe google 'exercises to strengthen core'?
I had exactly this for ages on my XC bike when I raced - could bimble around for hours on it without issue, but in a race I was quickly in lower back hell. Eventually traced to the seatpost slipping by about 10mm resulting in poor position/hips rocking. Once sorted - instant relief.
I have/had a similar problem. I found that it was actually a problem with tight hamstrings and glutes. Stretching these before riding and during helped alleviate the problem.
I altered my position slightly too and that helped...
Things like this are often complicated, just because one area hurts doesn't necessarily mean that is the area that is the problem.
First steps for me would be to work on flexibility and then on your core strength (in terms of abdominal lower back).
I found that it was actually a problem with tight hamstrings and glutes.
This, in my experience too. Stretching helps a lot.
I'd say if you can ride for 3 or 4 hours at a time with little discomfort, your position isn't too far out.