The energy flows through each meridian and its associated organ on a daily basis and in a set sequence. As there are 12 meridians and 24 hours in a day it can be seen that each organ is associated with 2 hours each. This forms a body clock of the daily cycle. The energy flows along the meridians in a set pattern, from one element pair to the next. The yin and yang meridians also follow their own rules;
Acupuncture has been practised in the east with other traditional Chinese medicines for over 5,000 years but it is only recently that scientists have been able to offer an explanation. They discovered that there were points on the skin where the electrical potential changes and that these coincide with the known acupuncture points. It is these points that are used to re-balance the energy flow along the meridians and if painful, can also indicate that there is a problem somewhere along the meridian or its related organ.
These points are usually activated with needles but they can also be stimulated with pressure, heat, laser torches, electricity or magnets. They can also be energetically activated with quartz crystals or by directing reiki energy into them
Not all meridians have the same number of points along them. The heart meridian on the arm has only 9 points whereas the urinary bladder meridian on the head, back and legs has 68.
During a massage or reflexology treatment, many acupuncture points are worked unconsciously. With more knowledge they can be worked with conscious intent, which will enhance the therapy.
It can also help to explain pain on the hands or feet during a reflexology session which does not seem to relate to the reflexology reflex. And in the same way, painful areas on the back or face during a massage.
You can find a useful chart of some of these points on the Indian head massage Chart
Exercise such as Tai Chi works on energising the 'bubbling spring', which is the first point on the kidney meridian as well as stretching the other meridians.