Since 1958 we have used a combined treatment for bronchial asthma with Western and traditional Chinese medicine, in which qigong takes a main role. From 1970's we extended this combined treatment to chronic bronchitis. On the basis of a comparatively good clinical effect, its mechanism has been further explored. In order to make more detailed clarification, we have used three new testing methods in the past three years to test the amplitude of diaphragmatic movement (by time distance or DT) and its form, the TcPO[sub 2] and TcPCO[sub 2] and the variation of pulsating pressure of the fingertip arterioles (P. P. F. ) before and after the qigong exercises. All showed significant difference. Here is the report summary:

1. Ventilatory movement of the right hemi-diaphragm studied by video-fluorography correlated with qigong 24 cases skilled in the qigong exercises were observed. Among them, 11 cases did the relaxation qigong exercises, 13 did the 'small qi cycle exercise' . Results of the video-fluorography showed the average value of the sum (DD) of distance traveled during upward and downward movements of the diaphragm before the relaxation qigong was 54.6mm ± 14.8mm; while that measured in performing of the relaxation qigong was 72.6mm ± 23.6mm, the statistical comparison of DD before and during the qigong exercises showed T= 2.96 (P< 0.05) . For the small qi cycle exercises the average value of DD before the performance was 46.3mm ±24.7mm; while during the qigong exercises the average value was 95.4 ± 57.4mm. Statistical comparison of DD before and during the small qi cycle exercises showed T=3.68 (P<0.01) . Observation of the difference of the movement of amplitude in the anterior, middle and posterior part of the diaphragm simultaneously 1/3 of the anterior was the smallest, 1/3 of the middle the largest and 1/3 of the posterior lies in between the two. There was no significant difference before and during the qigong exercises. We observed the time distance of the diaphragmatic movement (the distance moved in a fixed time period, DT mm/min. ), and discovered that in the middle stage of DT of the small qi cycle qigong there was one or more short standstill and a little fluctuation of DT (reverse movement in the course of respiratory cycle) in persons practising the small qi cycle exercise.

By video recording, an exact measurement was made of the DT. The statistical analysis of the values before and during the relaxation qigong showed T = 2.23 (P<0.05), whereas the values before and during the small qi cycle exercise showed T= 3.68 (P<0.01) . The expansion of DD leads to a decreased respiration frequency. This was more evident in the small qi cycle exercise. The frequency of respiration per minute reduced to 2-3 times. P<0.001 was found before and during the two forms of qigong. Prolongation of DT, reduction of respiration frequency and reduction of total quantity of diaphragmatic movement showed that during the qigong exercise the status of exhaustion nature of energy metabolism would be transformed to a status of energy storage. In terms of the disputed paradoxical abdominal respiration it was proved by the appearance of the reverse movement of diaphragm seen in the video recording. The X-ray diaphragm video recording gave better observation of the diaphragmatic movement than the ultrasound technique; thus a new testing method to explore the mechanism of the clinical effect and special status has been found.

2. TcPO and TcPO[sub 2] measurement: 30 cases in total were measured. Among them 22 had better qigong training. After exercises their TcPO[sub 2] all decreased (T=5.45, P<0.001 ) . 8 cases did not have good qigong training. Their TcPO and TcPO[sub 2] before and during the qigong exercise showed no significant difference (P<0.05) . Before qigong exercises the TcPO[sub 2] value was lower than normal and increased to the normal value after qigong exercises. It showed that qigong exercises would change the body status, from that of 'energy exhausting (oxygen exhausting)' to 'energy storing' ( TcPO[sub 2] ).

3. Testing by P. P. F.:
It was measured under the pressure 40 mm Hg, 50 mm Hg and 60 mm Hg. P. P. F. showed changes before and during qigong exercises. There were 10 cases tested under 40 mm Hg pressure, 9 cases under 50 mm Hg and 7 cases under 60 mm Hg. After qigong exercises P. P. F. increased to some extent in each case, but all within the normal range. P value was <0.05 -0.01. The fact explains the theory of 'blood is commanded by qi ' in traditional Chinese medicine. Qigong exercises may improve the blood circulation through the regulation of qi and blood of the human body.

4. Discussion:
According to the results of the three new testing methods, together with the experimental observation of the various biophysical phenomena in the past, we think that the mechanism of the curative effect of qigong in treating bronchial asthma and chronic bronchitis may be explained as follows:
( l ) Qigong can regulate the function of cerebral cortex and vegetative nerve system.
(2) Qigong can improve the function of respiration.
(3) Qigong can regulate qi and blood, ying and yang of the human body.
The X-ray video recording of diaphragm movement, TcPO[sub 2] test and P. P. F. test provide further evidence for the last two hypothesized mechanisms.

Mechanism of qigong in treating bronchial asthma and chronic bronchitis with the aid of new testing methods