I am sorry, it has been so long since I have written this.... time has flown by with travel, teaching, Christmas etc etc. Enough excuses!
This will end up being about riding, but bear with me as I tell you this story!
My travel included a wonderful holiday in the Dominican Republic before Christmas, and I had an amazing experience sitting in the front seat of a 'guagua', which is a Dominican minivan serving as a small bus, usually packed full of people and quite an experience! Not many tourists make it onto these, and I was rather proud of myself for being so adventurous, and for getting the best seat. (Being packed into the front like a sardine definitely beats being packed into the back like a sardine!) I was enjoying the scenery, the music on the radio, the excitement of heading towards a new place, and the general ambience. It then occured to me that I felt as if I was being carried along on a wave of energy, and the feeling - along with the upbeat Caribean music - reminded me of the 'trancedances' we used to do when I lived in London in my late twenties. I was a member of the Natural Dance Workshop, which often sponsored these, and we would dance into the night to great music, experiencing something that I suspect was the equivilant of 'runners' high'.
I then realised that I had a feeling in the back of my diaphragm that I know goes with my most skilled riding - which is indeed like being carried along on a wave of energy. I am now sure that I must have accessed the same physiology in our 'trancedancing' too, although I never identified it like this at the time.
Fortunately, you don't need to dance late into the night or have a transcendent experience in a Dominican minivan to experience this! It's very simple, though it might take some practice. If you are sitting on a firm chair you should be able to make your hands into fists, put them behind your pelvis, and push against something solid at the back of the chair's seat. Think about the back of your diaphragm, at the bottom of your ribcage, and keep pushing with your hands until that area starts to firm up. With luck you will get a pretty immediate response, but if not persevere and repeat the exercise frequently. Think of your diaphragm as it passes from the back of you to the front of you, and maybe even think of it as part of the wave of energy that could carry you along if you were riding your horse.
This exercise is actually the partner exercise to the one in my previous post, where you pull on the back of the chair. This accesses strength in the front of the diaphragm and the abdominal muscles, and is an essential part of bearing down. Strength in your back adds hugely to this, and who knows, it might even have an effect on the adrenal glands as they sit on the top of the kidneys, also affecting other parts of the endcrine system, and giving rise to the transcendent 'wave of energy' experience!
I hope I am not being too 'way out there' for you here, but really think that there might be something in this. It was a useful and fascinating insight for me, at least, and this kind of physiological change might well explain the 'high' that we can get from riding.