Hi Esom,
This is during descent, on dives of 50-100 ft. Relatively straight down, but I'm a reef crawler/spearo, so I look around a lot and often don't go straight down, nor does my head stay straight. The purpose is to increase my speed of descent without burning much 02 or slowing onset of DR.
Cool. I think there is quite a bit to it. I will try myself the next few days (i too do it intuitively from time to time). Some obvoius enough points right away:
If the head is allowed to move and roll backwards a little, this will help the preperation and start of the armpull to be smooth. This will be a true and actual connection the other way around too - if you want to have better orientation, an armpull will let the according headmovement feel funktional and effective.
In a more complex environment than "rope in the blue" precise steering and it´s perception as such has a particular taste and meaning. Steering is updating the divers position - but as well as his feel! Understanding through action, that your steer is precise, is the only (un)reasonable reason to truly let go of preventive tension. Armpulls do make a difference in this respect.
They are connected to orientation as explained above, they are more direct and more fine in adjusting direction than finkicks, also they have a more direct feedback which means that you feel yourself steering precisely, even
while exerting the armpull (e.g. it´s easy to vary the steering aspect throughout one armpull) ...this bit got a little condensed, read twice or ask please.
The mechanics of armpulls can help to transition into freefall. As spine and hips are pulled, this can serve as an information on the new configuration of tension, that will establish the transition from a kicking and its according tension (enabling kick-steering and kick-forcetransmission "headwards"), to a sink that can be executed much more gentle.
Also, varing the used movment itself is meaningful.
It can act as a symbol for the degrees of freedom and thus involvement of the diver. Like this the diver is much less a propulsion machine and more a free diver. - I believe efficient movement can only happen through high involvement of the hole diver. I´m sure armpulls can be a valuable part of a learningprocess towards good integrative technique - actually i know it for sure, as i used them in classes
.
thanks for bringing it up, regards