Re: rowing exersize
Simon, for what its worth here is an excerpt from a book I wrote to my grandchildren. Some of text refers to other context in the book.
From A Collage of Poppy's Life
FUNATORI -- FURUTAMA
I start by taking one natural step forward with my left foot. Leaving the right in the rear position. Now I widen the distance just a little further than my normal walking gate. At first I had to experiment and find a comfort distance. I place my hands close to my side at the hip joint. They are closed as if I'm holding a boat ore , but they are not clinched. Now I move center forward bending the front knee while extending the hands out to the front of my body. I visualize lifting the ores out of water shifting to the forward position lowering the ores into the water and pulling back. I do all this with as much hip and leg motion as I can. At the apex of the extension the center begins to move back as the back knee bends and the front knee straightens. The hands are brought to the side in line with the hip joint again.
I endeavor to move the tanden (center) in a straight even line with as little bobbing up and down motion as possible. With the movement forward and the expansion of the body the breath flows into the tanden. With the movement to the rear the body contracts and the breath is forced out. Throughout all these Aikido based exercises remember body expansion requires breath in and body contraction requires breath out. Movement and breath, breath and movement are one.
As the body expands with arms extended the air flows into the lungs. As the body contracts with hands drawn to the hip joint the air is forced out of the body, this creates a harmony of motion. Each full movement of the body requires a complete cycle of breath.
Now I go through the other half of this exercise. After doing the rowing exercise for a short time I stand with my feet about shoulder with apart. I cup the left hand over the right as if covering an egg. I lift my arms over my head and then bring them down front of the tanden. I begin to shake the hands just strongly enough to feel the movement throughout the body. I continue this for about five minuets before shifting back to the first part. Remember what I said about deep breathing and that 1750 ml. of air in the bottom of the lungs that can't be voluntarily expelled? That's the residual volume if you remember. During the shaking I believe that the level of the oxygen in the bottom of the lung is increased and the level of the carbon dioxide is reduced. This improves the over all oxygen count in the blood and increases the internal body heat. I have done this with folks in the snow and we melt the snow.
Saotome Sensei recommended I do this in the morning for a minimum of 45 minuets. I have found that it builds core heat in my body and if I then step into freezing water my skin pores will close down holding the heat inside for a short time as long as I continue to shake. I guess it's much like shivering to create body heat but done much more methodically. When I step out of the water and the pores of my body open the flood of sensation is beyond belief. It's like my universe explodes into brighter colors and more sounds, the senses are amplified and flooded. Sometimes it's almost to much to stand. I want to caution both of you that this is not to be done with out proper supervision by a skilled teacher and even in Japan they are getting fewer and fewer as the old ways are being rejected by the younger generation.
I have experienced the same feeling in an American Indiana sweat lodge ceremony after long hours of demanding physical challenges.