On the electrocardiogram in static exercise / 体力科学

ABSTRACT

1) A method of recording electrocardiograms during the performance of active hands-tanding exercise, passive handstanding, upright standing and upright standing with load were described. Data obtained from 19 normal healthy subjects were analyzed.<BR>2) For the analysis of exercise electrocardiogram, the most important is to grasp the characteristics of ECGs of the individual subjects. The control examination was made on the tracings of electrocardiographic changes in wave patterns, amplitudes, time intervals and electric heart axis due to four different lying postures (supine, prone, leftside, and right side) and to the respiratory movement by standard limb lead and special lead (MII) . Lead MII (modified standard lead II Manubrium sterni↔left leg) was used throughout the expe-riments. The paper speed was 50mm per second.<BR>3) During active handstanding exercise, the time interval (sec) shortened quickly in T-P and slowly in P-Q and Q-T intervals. A slight decrease in the amplitude of the T-wave were observed.<BR>4) During passive handstanding prolongation of R-R interval was observed. At the angle of ∠70° shifted from the horizontal prolongation of R-R (T-P) interval atarted, but no change in P-Q and Q-T intervals occurred. T-wave showed slight increasse in passive handstan-ding immediately after body shift, but no markable change appeared during the period of loading.<BR>5) During upright standing and upright standing with load shortening of R-R interval were observed, but no change in P-Q and Q-T intervals occurred. Amplitude of each wave did not change during the period of loading.<BR>6) It is suggested that during active handstanding increase in sympathetic activity accelerates the cardiac rate, on the other hand, increase in parasympathetic activity mediated through the buffer nerve system (sinus caroticus, aortic nerve) decelerates it during passive handstanding. It appears to be general that autonomic nervous system plays an important role in the static exercise.