Balance Training
It's either surf or flat / marathon, and which ever camp you're in; it's sort of expected that you will paddle the Avon. Is that pretty much on the money?
OK, so try this for a theory. Flat water marathon paddlers need to develop their balance skills, so that when they are near the end of a long race they minimize the effects of fatigue. After all, a smoothly run K1 is more efficient that one that wobbles a bit.
Surf paddlers need to be able read water so as to keep their boats running, and apply controlled bursts of power when picking up runners. Sound familiar? True power can only be applied when you are perfectly balanced.
Cross training is sounding pretty obvious, however the reality of having access to the boats would probably limit most people. In the perfect training world, I highly recommend having you're a training boat for your non-preferred water: a cheap second / third hand old banger of a boat. There are many second hand skis for sale, all that will do that job of teaching you balance, and give the flat water paddlers a much needed change of scenery.
Likewise, a cheap K1, even one with 'hips' will teach the ocean paddlers balance & power, and give them something to use when the ocean is blown out.
Cheers, WP.
Balance training
I tried smashing a few beers ... didn't work ... listen to the experts, not me :-)
Seriously though, like most things paddling, it takes time and practice (and I am still practicing). Just get out there in some rough stuff. Not stupidly rough, just a little bit rougher than you feel comfortable in. If not comfortable, stay near the shore so you don't have far to swim if you have to.
Surf is fun and helps with balance, as does paddling near reefs where the water moves around a lot (plastics preferred). I found it helped get me into the basics of white water, and helped with confidence. However, surf is quite different to white water. In surf (on a wave), you have a lot of boat speed (water going fast under the kayak/ski). In white water, you might think you are going fast relative to the river bank, but your actual speed through the water may not be so good.
I have tried (and still try) padding a very unstable boat to learn balance (or pad your seat right up). I'm not sure this is a good thing. I think I am getting good balance training, but at the same time, my paddle technique suffers as I focus on staying upright. However, when I get back in my PRS in the white water, it feels very stable and I have a lot of fun with this confidence ... shame the paddle technique is still average!
I think any time on the water is a good time, so just paddle regardless, we'd all rather be paddling.
I'm keen to hear real paddlers feedback on this one.
Balance training
I agree with the suggestions by others. Also if you go to this link you can see some technical stuff about core strength and balance
http://www.surfski.info/getting-started/tips-training/item/1130-core-str...
I go with time in the boat in varied conditions, but after almost a year I am still trying to get good balance ocean paddling in my Finn Molokai. I haven't tried it in white water, I had enough trouble getting balance in my DR.
RA
balance/trees
Balance: do the choppy bits of the Swan river:
-on a w or SW off Majesic/applecross bank, Como Jetty, Narrows jet ski area, Riverside drive near causeway (reflected chop vs wind wave)
-on a N/NW with outgoing tide north of canning bridge with superb standing waves.
Try to paddle in the chop while maintaining your normal rhythm.
If this isn't enough challenge, raise your seat up. I train on 40ml foam booster seat- makes it much more unstable. When I race on the low seat I feel so much better (still bad)
Ti trees- do lots of ti tree runs.
Balance Training
I found that Kneeling on a fit ball does help. Power yoga is better! Surfing seems to help me get down rapids. Does anyone have any tips for me to gain better control of the old girl (my plastic fluid druid) in the tea tree.