There's also prana and ruach. But all those are just names, not explanations or even descriptions.
Clint: There are names for ULE from every culture that has discovered it. I have seen a a list of 15-20 different names for lifeforce energy.
I had a book (now lost) by an aikidoka who claimed there is no such thing as ki; it's all physics, anatomy, psychology and confidence. I don't agree entirely, but a lot of things the aikido
I must disagree with that book. ULE is a real force that can be directed with the mind.
Is the chi that circulates through the acupuncture meridians the same as the chi that you use to heal?
Yes. There is only one universal lifeforce energy.
Qigong, HUNA, etc healers gather a surcharge of energy via deep breathing before the healing.
Actualism, pranic healing, Reiki, Seichim, Silva Mind Control, Therapeitic Touch, etc either use the lifeforce of the healer. or consciously tap into the sea of ULE all around us.
That a small person can use to throw a large person? (Do those meridians even exist except as a theoretical construct?)
Physical strength is not important. Mental strength, and the ability to focus the mind into a one pointed concentration, and the ability to direct the lifeforce is very important.
Yes; I believe the meridians are real. Because I can feel the energy flowing through my body when I still my mind, AND I can feel the areas where a person has blocked meridians by scanning the person with my hands about 4-6 inches above the body.
There are some qi gong excercises you can do that will let you feel the chi in your hands, and after a lot of practice you can feel it in your arms & then your whole body.
One of the best ones I have seen to experience qi in your hands and arms is the Zhan Zhuang pose "Holding the balloon in front of your face" from the book "The Way Of Energy" by master Lam Kam Chuen.