after the best day as im fairly new to the sport and doing really long runs on flat water my back locked up and i needed major physio. could this be all my fault through bad technique or could my seat harness be part of the problem which does make me stick my butt out a bit just wearing it. anyone please!!

pepeman I just changed from a seat to a prolimit waist harness. This has had an imediate effect on my stance. Took 2 sesions to get used to but I will never go back to a seat. It has taken some time to find one that complements my beer gut and doesn't slide up and crush my ribcage. Enter the pro limit hadlow. Have a look at the latest "Online kite surf magazine" There is an excellent section on proper stance.

Hey pepeman,heeps of people get saw backs,I have followed a great sugestion by a Seabreezer.Purchase a pair of quality 'booties',insert a pair of 'arch supports' soles from the chemist.They won't cure your acheing back but they definately take the edge of the rough riding associated with kiteing and make for a smoother ride especially when your posture is not a 100%(like mine)also fish oil capsules and Glucosamine, vitamins with a high level of magnesium will aid in the repair of tendons n ligaments...Roo

My back fixed up once I could touch my toes, I think?
Learn to touch your toes after kiting and relax your arms and shoulders periodically while kiting.

Stretch before and after kiting.

Sort out your core muscles,go do pilates(there are heaps of chicks if you don't like it, or other kiters with bad backs.)

don't fly in overpowered conditions

Lose the pooman stance by leaning your entire bodyweight against the kite and try and "lie" against the angle of the kite/board/edge.

It doesn't make much difference on the "type" of harness you use, but rather the quality. Buy a new, heavily padded/re-enforced one and remember to buy from your local dealer.