Through centuries of practice, many different schools of Chinese mind and body exercises such as qigong - breathing exercises - and taiji - commonly known as Tai Chi in the West - have proven to help improve health and even possess some healing powers.

According to traditional Chinese medical theories, these exercises, which involve regulation of the mind, body and respiration, enhance the development and circulation of qi, the vital energy in the body.

However, qi has remained somewhat elusive to modern medical science as it is yet to be measured and proven to exist.

Shin Lin, a research fellow from the International Alliance for Mind/Body Signaling and Energy Research in the United States, and his research fellows are now applying the latest biomedical technologies to gain a better understanding of the physiological aspects of such effects.

"Through our research, we hope to deduce important elements responsible for good health and healing in order to develop simplified body training routines and medical treatments," said Lin.

Lin shared his most recent research at the 10th International Symposium of the Society of Chinese Bioscientists in the United States, which was held in Beijing last week.

As part of an on-going study, different types of measurements were made on more than 20 high-level qigong and taiji practitioners and several control subjects, at Alliance laboratories. A series of effects on general health have been identified, Lin said.

Researchers from the laboratory find that when the taiji practitioners are doing movements, which are co-ordinated with deep breathing cycles, there is a big increase in peripheral blood flow.

While achieving the effect, researchers find that practioners must be relaxed.

"Any mental stress will restrict blood flow and accordingly reduce the effect on blood flow," Lin explained.

In theory, brain tissue will harden with age. However, after measuring the brain response of some qigong practioners who have trained many years, results show that their minds are as responsive as people in their 20s.

Lin believed that the result is related to their breathing exercises, which allow more oxygen to reach the brain. This way, they can keep their brains as flexible and elastic as the young people.

Next, researchers use Heart Rate Variability analysis of electrocardiograms to follow changes in the autonomic nervous system among the practitioners.

When qigong practitioners enter a deep meditative state involving mind regulation, they show a pattern of high-frequency heart rate variation indicative of relaxation normally seen during deep sleep.

Lin noted that international researchers have also tried to distinguish the effects of qigong and taiji exercises by measuring electrical conductance at acupuncture points.

After measuring the conductance of the qigong masters before they do taiji or qigong and immediately after they practise for 20 minutes, researchers found that there was a15 to 30 per cent of increase in electrical conductance.

In contrast, physical exercises such as lifting weights and riding a stationary bicycle in the control group produced little or no effect.

The contrast in the power of conducting electricity is thought to reflect the strength of the acupuncture points and the result can be taken as evidence of the overall beneficial effects of qigong practice.

In conclusion, emerging data from collaborative studies at Alliance laboratories show that qigong and taiji practices lead to measurable changes in mind and body functions that can be explained in part by conscious control of the autonomic nervous system.

"Our research will develop some standards which can monitor training like qigong so that people who practise the art can know that they are making progress," Lin said.

In addition, the researchers also found in their experiment that acupuncture treatment and accupoint massage<