Out-of-the-saddle technique

When you're pedalling out-of-the-saddle/off-the-saddle, should you lean the bike side-to-side, or try to maintain the bike in a vertical position? Which is more efficient?

I think most would ride as the dude in the black and white bib does in the video below:
http://www.youtube.com/watch?v=WgTFENouM7w&hd=1

Not sure about efficiency, but I'm sure it puts a hell of a lot of strain on your bike when you wobble side to side.

Look at Cavendish as he sprints. He manipulates the bike from side to side to incorporate upper body strength into a powerful pedal stroke. This is a common sprinting technique. Are you referring to sprinting or climbing?

If it's climbing, have a look at this:

http://www.lfgss.com/thread2171.html#post62402

Facial expression and grunting is more important, I find, for sprinting out of the saddle.

if you have to get out of the saddle you are weak.

if you have to get out of the saddle you are weak.

if you are like me its a case of I am too weak to lift myself up into a standing position when going up a hill

Rocking or not is a question of how you time the (whole body) pedalstroke, and how knackered certain muscle groups are. If you're feeling strong, and cycling with absolute efficiency, the rocking will be less. Examples might be the initial burst of attack from someone like Pantani, or the first 250m of a kilo by a great technician. Shoulders, hips, knees, and ankles in perfect alignment as the foot pushes through the power section of the stroke around 2 to 3 o' clock.

But as muscle groups fatigue, sometimes you have to throw yourself or the bike around a little more to eke out some power. Road sprinters like Cavendish are massively pre-fatigued as they approach the final 500m, so it's no surprise their style can be a little untidy, although Cavendish is nowhere near as ragged as Abdoujaporov :D

^ agree.
And if you look at the way Contador "dances" on the pedals whilst climbing, its a way of compensating for a lighter body weight. In a smooth, rythmical (clenbuterol fuelled) way, he utilises his body weight to add an extra kick to his pedal stroke, which makes him an excellent, short burst hill accelerator.

look at the way Contador "dances" on the pedals whilst climbing

Much as he may well be a massive cheat, I still think Wee Bert taking off up a hill is amongst the most aesthetically pleasing sights in pro cycling.

pffft

Fabian making everyone look pedestrian; compare and contrast

http://www.youtube.com/watch?v=6T7TOTu3MyU

fab dumps it in second gear and hits the nitrous oxide

When you're pedalling out-of-the-saddle/off-the-saddle, should you lean the bike side-to-side, or try to maintain the bike in a vertical position? Which is more efficient?

When climbing you should not really let the bike move about excessively. Most climbs will be about efficient pedaling over the distance rather than getting raw power down for a short time.
For sprinting on the track, and on the road to a certain extent, when applying lots of power it's beneficial to move the bike from side to side whilst keeping the head and body central; the bike goes the opposite way to the leg which is applying the stroke (push down with right leg, bike goes left)

clearly technique is important. if you are out the saddle and moving your body up and down you can be wasting energy as the effort of lifting your body up does not necessarily convert into downward pedal force from gravity. im pretty sure ive read that standing up does take more energy but as it uses different muscles it can offer light relief to the muscles that have already been tired from using the more efficient sitting down approach. i would imagine that your riding position (saddle height, frame geometry, stem length etc) and the different muscles that relies on will have the most effect on the difference in energy use between standing and sitting.

If you are climbing out of the saddle other than for the "kick" round a hairpin etc, you have lost the efficiency battle before you have even started, so do what you want and watch the spinners up ahead,

I prefer to climb in the saddle, but getting out the saddle is good to use those other muscles.

I rock the bike a little, for rhythm, or a lot if I'm fucking tired and need the help from my arms.

I prefer to climb in the saddle, because last time I climbed a load of hills standing up I hurt my back :(

I vote get stronger legs and try to remain seated whenever possible.

I'm not sure if many do it, but i really favour climbing seated, in the drops. I have no idea why i do it, as club riders always tend to give me grief about it ("less efficient etc"). I' do climb on the hoods every now and then, but i just feel more comfortable in the drops. Thats weird, right?

On short climbs, those who are strong out of the saddle will just ride away from the sitters. They're probably quite strong sitting down too (power-to-weight is power-to-weight). On long climbs, it's nice to have options.

Absolutely.

Anything that can be ascended at speed without worrying about fatigue I'll attempt out of the saddle. Best to hammer away, confident that the summit will arrive before significant discomfort.

Sitting and spinning is the better approach for anything that requires moderation.

Standing and rocking does indeed help to distribute the strain; though I often find that the energy consumed by getting up and adjusting would have been better spent gritting teeth and digging in. I've never really thought about it until now, but I reckon that dropping a gear or two would be more or less equal to lollopping about, both in terms of pain relief and maintaining speed.

Ultimately, this:-

...it's nice to have options.

...makes sense to me.