Triathlon - running/cycling breathing technique help

I'm training for my first series of tri's this summer and I'm just wondering if there is a proper way of breathing or if it's just whatever works for you. Right now for running I am breathing in through my nose and out through my mouth. I'm not sure if I should be focused on my cadence just yet, but any pointers on that too?
As far as cycling goes, I don't pay too much attention to my breathing but it's roughly the same as running. Again I haven't paid too much attention to cadence but any pointers?
Thanks for any help and I'm getting pretty excited about doing my first tri's.

For running and cycling - whatever works best for you. I keep my mouth open and breathe in and out through the mouth.

i found I run harder,faster with an ipod where I can't listen to my breathing. When I dont take my ipod I listen to my breathing which makes me feel like I'm outta breath.

I'd love to know the secret also, i breath in & out my mouth

i believe that whatever works for you or whatever you're comfortable with. however, expanding your stomach/diaphragm conserve more of your energy than expanding your chest when inhaling.

I find I breath in thru the nose and out thru the mouth. Try and keep my back vertical on the run, keeps the diaphram open. Works for me, gets me thru the run.

For running i believe you are supposed to find a rhythm to your breath depending on how you are running. So breathe in X steps out X steps. An example is I breathe in for 3 steps and breathe out for 2 steps when running moderately, but when running fast it is breathe in 2 steps and breathe out for 1 step. I usually breathe in through both mouth and nose at the same time since the nose doesn't supply me fast enough then breathe out through both. Supposedly, a good breathing ratio also helps prevent injury by balancing your body, not sure about this though.

For cycling i need still need to find my rhythm!

http://www.runnersworld.com/article/0,7120,s6-380-381-386-245-0,00.html
PUBLISHED 08/28/2001

When you run, you get out of breath. This is normal. This is natural. Your body runs on oxygen, just as your automobile runs on gasoline. When you start to exercise--whether running, walking or any other physical activity--your muscles need more oxygen. The body meets this need by supplying oxygen-rich blood to the muscles. The lungs work harder to absorb this oxygen out of the air.

You get out of breath.

Without giving it much conscious thought, most runners breathe in a 2/2 rhythmic ratio. They take two steps as they inhale; they take two more steps as they exhale. While running very slowly, they often breathe in a 3/3 ratio. While running very fast, they might breathe 2/1, or 1/1, but 2/2 is much more common.

If you count breaths in and out and discover you are breathing with a different rhythm, don't worry about it. Adjusting your breathing pattern will not make you a better runner.

The same with whether you breathe through your nose or your mouth. Most runners naturally breathe through both. Famed New Zealand coach Arthur Lydiard, when asked how runners should breathe, once replied: "Breathe through your mouth. Breathe through your nose. Suck the air in through your ears, if you can."

Your jaw should be relaxed, your mouth slightly open. The oxygen will come through your nose and mouth to your lungs, to your blood and to your muscles without you needing to give it a lot of thought. Breathing is a very natural activity--and so is getting out of breath when you run.

as for the 3-2 and 3-3 or 2-2 steps note that this does not actually change much. I have had to do special breathing, but that only begins to happen at 10,000+ feet while mountaineering. To get the most air at ultra high altitude, you suck in air, hold for a step, then push out air quickly. At altitude, it turns out that doing that just puts you at how much oxygen you normally get. Try it down here, and you will soon get a headache from hyperventilation.

I read that exhaling through pursed lips helps build more pressure in the alveoli and increases the osmosis of gasses into the bloodstream. I run and cycle breathing with my mouth and when I feel I need a little bit more help I start exhaling through pursed lips to increase the exchange and improve my performance. I don't see the sense with breathing in through your nose. it just restricts air flow.

that said, I've read about benefits from breathing your nose to include include cooling the brain; warming the air and filtering suspended particles.

(scroll down to good diagram)
http://learningat.ke7.org.uk/scienceweb/alevel/biology/AS%20Interactive/e-a-level/10/10.7.htm