건강상식 II-잘못 알려진 만병 통치약-엔도르핀

황수관,Hwang, Su-Gwan 한국자연공원협회 1997 한국자연공원 Vol.66 No.-

서울조합 경영자 및 관리자 세미나

황수관,Hwang, Su-Gwan 대한인쇄문화협회 2002 프린팅코리아 Vol.5 No.-

Disciplinary Session 8 / Sport Physiology / Health , Exercise Prescription & Others : 정상인과 성인병 집단에서 동맥경화 지수가 관상동맥 위험 인자 및 유산소성 운동 능력에 미치는 영향

김남익,황수관 ( Nam Ik Kim,Sook Won Hwang ) 한국체육학회 1998 국제스포츠과학 학술대회 Vol.1998 No.2

Treadmill 최대 운동시 Impedance 심장기록법의 개선에 의한 마라톤 선수의 심박출량과 산소소비량과의 관계

강두희,황수관,연동수,유선희,김덕원,Kang, Doo-Hee,Hwang, Soo-Kwan,Yeon, Dong-Soo,Yuh, Seon-Hee,Kim, Deok-Won 대한생리학회 1990 대한생리학회지 Vol.24 No.2

Maximal cardiac output and oxygen uptake $(VO_{2max})$ were measured during treadmill exercise for seven top-class marathoners and nine non-athletes using impedance cardiograph developed by one of the authors (DW Kim). Results of this study are summarized as belows. 1) New shoes with sponge and silicon rubber attached to the soles were developed to reduce motion artifact during treadmill exercise. Ensemble everaging techneque with the developed shoes was also used to improve the measurement of stroke volume using impedance cardiography. 2) Maximal cardiac output of the athletes, 14.98 L/min, was significantly higher than that of the non-athletes, 13.46 L/min. As maximal heart rate of the marathoners is lower than that of non-athletes, stroke volume of the former is significantly larger than that of the latter. 3) $VO_{2max}$ of the marathoners, 59.38 ml/kg/min, was higher than that of the non-athletes, 40.22 ml/kg/min. At the anaerobic threshold. $VO_{2max}$ of the former was 62.3% of $VO_{2max}$ and this was significantly higher than that of the non-athletes, 57.2%, This results indicates that the marathoners have higher aerobic capacity than the non-athletes. 4) The marathoners showed larger $VO_2$ than the non-athletes at the same cardiac output, indicating that a-v $O_2$ of the former is higher than that of the latter. 5) Maximal systolic pressure of the marathoners was higher than that of the non-athletes, and so was maximal rate-pressure products. These results indicate that heart oxygen consumption rate $(hVO_2)$ of the marathoner is higher than that of the non-athletes is mainly due to higher stroke volume. And higher oxygen consumption of the marathoners is due to higher stroke volume. And higher oxygen consumption of the marathoners is due to their larger a-v $O_2$. The marathoners show both higher threshold and $VO_{2max}$. Especially, measurement of cardiac output during treadmill exercise by improved impedance cardiography is expected to contribute in study of cardiac function of athletes.

임피던스 방법을 이용한 체지방 측정

김덕원,송철규,황수관,Kim, Deok-Won,Song, Chul-Gyu,Hwang, Soo-Kwan 대한의용생체공학회 1992 의공학회지 Vol.13 No.2

Bioelectrical Impedance method for measuring human body composition is based upon the principle that the electrical conductivity of the fat-free mass (FFM) is far greater than that of the (at. Deter- mination o( impedance was nlade in 30 healthy and obese men aged $40.9{\pm}14.7$yr (mean${\pm}$SD) and 25 healthy and obese women aged $44.0{\pm}10.2$ yr. A commercial impedance body fat analyzer was used with a four electrode arrangement that introduced a painless constant current(ImA at 50 kHz) into the body. Linear relationships were found between impudence values and FFM(r=-0.786) and between weight and FFM(r=0.837). Signigicant increases in the correlation coefficients were ob served when the predicator Hta/z was regressed against FFM(r=0.912) where Ht Is height and Z Is impedance. A linear regression equation, FFM=0.586(Htf/z) +0.317(Weight) -1.674(r=0.977), was found. The correlation coefficient of % body fat between the impedance and infrared methods was 0.898. These data Indicate that the bioelectrical impedance technique is a reliable and valld approach for the estimation of human body composition. This method Is safe, noninvasivr, prouides rapld measure menu, requires little operator skill and subject cooperation, and Os portable. Finally measurement of percent body fat was made possible using both the regression equation and a developed impedance measuring device which measures impedance between wrist and ankle.

운동종목별(運動種目別) 선수(選手)의 심전도시간간격(心電圖時間間隔), 파고(波高) 및 벡터의 비교(比較)

권기영,이원정,황수관,주영은,Kwon, Ki-Young,Lee, Won-Jung,Hwang, Soo-Kwan,Choo, Young-Eun 대한생리학회 1985 대한생리학회지 Vol.19 No.1

운동종목별(運動種目別) 선수(選手)들의 심기능(心機能)을 비교(比較)하기 위하며 운동경력(運動經歷)이 3년이상(年以上)이 된 고등학교(高等學校)의 투척(投擲)(7명), 도약(跳躍)(11명), 단거리(短距離)(8명), 장거리(長距離)(14명), 권투(拳鬪)(7명), 배구(排球)(8명) 및 야구(野球)(9명) 선수(選手)와 비선수(非選手)(19명)들의 안정시(安靜時)심전도상(心電圖上)에 나타난 시간간격(時間間隔), 파고(波高) 및 vector를 비교(比較) 분석(分析)하였다. 안정시(安靜時)의 R-R(간격)間隔은 각종목별(各種目別) 선수(選手)들은$0.96{\sim}1.09$ 초(秒)로 비선수군(非選手群)의 0.78초(秒)에 비(比)해 유의(有意)한 서맥(徐脈)을 보여주었다. R-R간격(間隔)은 P-R, Q-T 및 T-P간격(間隔)의 합(合)으르 나타나는데, P-R 및 Q-T간격(間隔)은 각(各 선수군(選手群)과 비선수군간(非選手群間)에 차이(差異)가 없었으나 T-P간격(間隔)은 도약(跳躍), 단거리(短距離), 장거리(長距離) 및 권투선수(拳鬪選手)들에서 비선수군(非選手群)보다 유의(有意)하게 높았다. R-R간격(間隔)은 T-P 및 Q-T간격(間隔)과 유의(有意)한 상관관계(相關關係)가 있었으나 P-R 및 QRS간격(間隔)과는 상관관계(相關關係)가 없었다. 심전도(心電圖)의 파고(波高)를 비교(比較)해 보면 lead $V_5$에서의 P파고(波高)$(Pv_5)$는 비선수군(非選手群)에 비(比)해서 각종목(各種目) 선수군(選手群)이 전반적(全般的)으로 낮은 경향(傾向)을 보여주었고, 특(特)히 투척(投擲) 및 도약선수군(跳躍選手群)은 유의(有意)하게 낮았다. T파고(波高)$(Tv_5)$는 투척선수군(投擲選手群)이 비선수군(非選手群)보다 유의(有意)하게 낮았으나 다른 선수군(選手群)들은 차이(差異)가 없었다. R파고(波高)$(Rv_5)$는 장거리선수군(長距離選手群)을 제외(除外)한 다른 종목선수(種目選手)들과 비선수(非選手)사이에 차이(差異)가 없었다. 장거리선수군(長距離選手群)의 $(Rv_5)$파고(波高)는 비선수(非選手)뿐만 아니라 다른 종목선수군(種目選手群)보다도 유의(有意)하게 높았다. Lead $V_1$에서의 S파고(波高)$(Sv_1)$는 선수군(選手群)과 비선수군(非選手群)사이에 차이(差異)가 없었다. $Rv_5$와 $Sv_1$파고(波高)의 합(合)은 장거리선수군(長距離選手群)만이 다른 종목선수군(種目選手群)들이나 비선수군(非選手群)보다 유의(有意)하게 높았으며 다른 선수군(選手群)들은 비선수군(非選手群)과 차이(差異)가 없었다. 심전도(心電圖)의 vector를 비교(比較)해 보면 P, QRS, T축(軸)의 각도(角度)는 frontal 및 horizontal plane 상(上)에서 각선수군(各選手群)과 비선수군(非選手群)사이에 차이(差異)가 없었다. P vector의 길이는 각선수군(各選手群)이 비선수(非選手)보다 낮은 경향(傾向) 나타냈으며, 특(特)히 horizontal plane에서 투척(投擲), 도약(跳躍), 단거리(短距離) 및 야구선수(野球選手)들이 비선수군(非選手群)보다 유의(有意)하게 낮았다. QRS와 T vector의 길이는 선수군(選手群)과 비선수군간(非選手群間)에 차이(差異)가 없었고, 야구선수(野球選手)만이 frontal plane에서 QRS vector의 길이가 비선수군(非選手群)보다 높았다. 이상(以上)의 결과(結果)를 종합(綜合)해 보면 각종목(各種目) 운동선수군(運動選手群) 전반(全般)은 비선수(非選手)보다 유의(有意)한 서맥(徐脈)을 나타내며 이는 주로 T-P 간격(間隔)이 길기 때문이다. 파고(波高)의 높이와 vector를 비교(比較)해 볼때 각종목( In order to compare the cardiac function of various groups of athletes, the resting electrocardiographic time intervals, amplitudes and vectors were analyzed in high school athletes of throwing(n=7), jumping(n=11), short track(n=8), long track(n=14), boxing(n=7), volleyball(n=8) and baseball(n=9), and nonathletic control students(n= 19). All athletic groups showed a significantly longer R-R interval(0.96-1.09 sec) than the controls (0.78 sec). Therefore, the heart rate was significantly slower in atheletes than in the control, but was not different among the different athletic groups. R-R interval is the sum of intervals of P-R, 0-T and T-P: P-R and Q-T intervals showed no difference among the control and athletic groups, but T-P interval in the jump, short track, long track and boxing groups was significantly higher than the control. R-B interval showed a significant correlation with T-P or Q-T intervals but no correlation with P-R or QRS complex. Comparing the amplitude of electrocardiographic waves, the athletic groups showed a lower trend in P wave than the controls. T wave in lead $V_5\;(Tv_5)$ was similar in the athletic and control groups. The long track group showed a significantly higher waves of $Rv_5$, $Sv_1$, and the sum of $Rv_5$ and $Sv_1$ than not only the controls but also the other athletic group. The angles of P, QRS, and T vector in the frontal and horizontal planes were not different among the control and all the athletic groups. Each athletic group stowed a lower trend in amplitude of P vector in the frontal plane, but in horizontal plane, throwing, jump, short track and baseball groups showed a significantly lower than the controls. The amplitude of QRS and T vector was similar in the athletic and control groups, but only the baseball group showed a significantly higher QRS vector in the frontal plane. In taken together, all the athletic groups showed a slower heart rate than the controls, mainly because of elongated T-P interval. Comparing the electrocardiographic waves and vector, the athletic groups showed lower amplitudes of P wave and P vector than the controls. Values of $Rv_5$ and $Sv_1$ strongly suggest that only the long distance runners among the various athletic groups developed a left ventricular hypertrophy.

체력단련(體力鍛鍊)이 폐기능(肺機能)에 미치는 효과(效果)

남팔수(Nam, Pal-Soo),황수관(Hwang, Soo-Kwan),김형진(Kim, Hyeong-Jin),주영은(Choo, Young-Eun) 대한생리학회 1981 대한생리학회지 Vol.15 No.1

장기간(長期間)의 체력단련(體力鍛鍊)이 폐기능(肺機能)에 미치는 영향(影響)을 알아보고자 운동선수군(運動選手群) 24명(名)과 비운동선수군(非運動選手群) 12(名)에 대(對)하여 실시(實施)한 본(本) 연구(硏究)의 결과(結果)를 요약(要約)하면 다음과 같다. 호흡수(呼吸數), 일회호흡량(一回呼吸量) 폐활량(肺活量)은 실시군(實施群)과 비실시군(非實施群) 사이에 유의(有意)한 차이(差異)가 없었으나, 최대환기능(最大換氣能)은 선수군(選手群)이 148.1±3.01 L/min, 비선수군(非選手群)이 1118.3±9.1 L/min 로서 선수군(選手群)에서 비선수군(非選手群)에 비(比)해 유의하게(p<0.01) 높았다. 초시폐활량(秒時肺活量)은 선수군(選手群)이 3.310±0.070 L, 비선수군(非選手群)이 2.279±0.104 L였고, FEV₁ 25~75%는 선수군(選手群)이 83.63±1.29%, 비선수군(非選手群)이 75.33±1.75%로서 둘 다 선수군(選手群)에서 비선수군(非選手群)에 비(比)해 유의하게(p<0.01)높았다. FEF 0.2~1.2L는 선수군(選手群)이 297.7±13.5 L/min, 비선수군(非選手群)이222.7±15.0 L/min였고, FEF 25~75%는 선수군(選手群)이 3.543±0.109 L/sec, 비선수군(非選手群)이 2.719±0.142 L/sec로서 둘다 선수군(選手群)에서 비선수군(非選手群)에 비(比)해 유의하게(p<0.01)높았다. 이상(以上)의 결과(結果)를 종합(綜合)하면 선수군(選手群)과 비선수군(非選手群) 사이에 폐용적(肺容積)은 별차이(別差異)가 없으나, 최대환기능(最大換氣能), 초시폐활량(秒時肺活量), FEV₁%, $FEF 0.2~1.2L, FEF 25~75% 등(等)은 선수군(選手群)이 비선수군(非選手群)에 비(比)해 유의하게(p<0.01) 높은 측정치(測定値)를 나타내었으며, 이것은 선수군(選手群)에서 비선수군(非選手群)에 비(比)해 호흡근(呼吸筋)의 힘이 더 강(强)하거나, 폐(肺) 및 흉곽(胸廓)의 용압률(容壓率)이 더 크기 때문인 것으로 사료(思料)된다. In the present study, an effort was directed to elucidate the effect of the physical training on the pulmonary function. Twenty-four male athletics major students who have undergone regular physical training for more than five years were randomly chosen as the athletic subjects, and 12 regular male students who have not been engaged in any form of regular physical exercise or training were chosen as the non-athletic subjects, and a comparison was made between the two groups. The following were mainly observed by spirometry for the study; respiratory rate, tidal volume, vital capacity, maximum voluntary ventilation(MVV), forced expiratory volume for 1 second(FEV₁), percent FEV₁ to forced vital capacity(FEV_1%), forced expiratory flow for initial 1 liter(FEF 0.2~1.2L), and forced mid-expiratory flow(FEF 25-75%). The results obtained are summarized as follow. 1) The respiratory rate, tidal volume, and vital capacity showed no significant difference between athletes and non-athletes. The MVV in athletes was significantly (p<0.01) increased to 148.1±3.1 L/min comparing with 118.3±9.1 L/min in non-athletes. 2) FEV₁ was 3.310±0.070 L in athletes and 2.779±0.104 in non-athletes; FEV₁% 83.63±1.29% in athletes and 75.33±1.75% in non-athletes, both showing significant(p<0.01) increase in athletes. 3) FEF 0.2-1.2L was 297.1±13.5 L/min in athletes and 222.7±15.0 L/min in non-athletes; FEF 25-75% was 3.543±0.109 L/sec in non-athletes, both showing significant(p<0.01) increase in athletes. 4) Some discussions were made on these results. The lung volumes showed no significant difference between the two groups. But MVV, FEV₁, FEV₁%, FEF 0.2-1.2L and FEF 25-75% in athletes were significantly(p<0.01) higher than in non-athletes. It is therefore concluded that the athletes have more powerful respiratory muscles, or higher compliance of the lung and thorax than the non-athletes.

건강교육 : 본태성 고혈압환자에서 운동중 혈청지질이 혈압에 미치는 영향

정영자,최건식,어은실,황수관 ( Y . J . Jung,K . S . Choi,E . S . Eo,S . K . Hwang ) 한국체육학회 1993 국제스포츠 학술대회 Vol.1993 No.-

단련한 흰쥐의 속근 및 지근에 Glycogen 과저장이 운동 지구력에 미치는 영향

연동수(Yeoun, Dong-Soo),황수관(Hwang, Soo-Kwan),김인숙(Kim, In-Sook),고성경(Ko, Seong-Kyeong),남택상(Nam, Taick-Sang),강두희(Kang, Doo-Hee) 대한생리학회 1988 대한생리학회지 Vol.22 No.1

This study was carried out to investigate relationships between maximal running time (MRT) and glycogen supercompensation in fast twitch white fibers (white vastus, WV), fast twitch red fibers (red vastus, RV) and slow twitch red fibers (soleus muscle, SM) of endurance-trained rats. Male rats of a Sprague-Dawley strain were divided into the trained groups and untrained groups. Untrained groups were acquired to run on the treadmill 10 minutes for 3 days and remained rest and maintained with mixed diet for 4 weeks. For last 10 days of resting period, the untrained rats were divided into 3 groups i.e. mixed diet (untrained control), high and low carbohydrate (CHO) diet groups. And each group was subdivided into 2 groups, one group was tested for the MRT and the other was sacrificed to measure the blood glucose, blood lactate, glycogen contents of liver and muscles. The experimental groups were trained on treadmill by a modified method of Constable et al. (1984) maintained with mixed diet for 4 weeks. After measurement of MRT of this group, they were also divided into high and low CHO groups and fed with these diet for 2 days and MRT of each group was measured again to see the effect of high or low CHO feeding on the MRT. Each group was maintained with the same diet for next 2 days during which some of the rats were sacrificed at given time intervals for the measurements of blood glucose and lactate, liver and the muscles glycogen. The results were summarized as follows; 1) In the untrained group, there were no significant differences between subgroups in MRT, glycogen conent of SM, RV and WV. But blood glucose concentration and glycogen content of liver of low CHO group were significantly lower than those of mixed diet group. 2) The MRT and glycogen content of SM, RV and WV of trained mixed diet group were significantly increased compared to those of untrained mixed diet group, but there was no significant difference in glycogen content of liver. 3) MRT of trained mixed, high CHO and low CHO groups were 137±9.8, 176±9.8 and 129±7.3 min respectively with the significant difference between them. 4) There were no differences in blood lactate concentrations between the trained high and low CHO groups immediately after maximal running and during recovery period. 5) Glycogen contents in RV and SM of trained high CHO group were significantly increased, and glycogen contents in RV, WV and liver of trained low CHO group were significantly decreased compared to those of trained mixed diet group. 6) Immediately after maximal running, the blood glucose concentrations of trained high CHO and low CHO groups were 73±4.0 and 67±6.9mg% respecitively. The blood glucose of the trained high CHO group was fully recovered within one hour by feeding. But blood glucose concentration of low CHO group was slowly recovered up to 114±4.1mg% after two hours of feeding and maintained. Those values were still significantly lower than that of trained mixed diet group. The synthetic rates of glycogen in liver and muscles during the recovery period followed the similar time course of the blood glucose recoveries in each group. These results suggest that an increase in MRT of trained high CHO group was attributed to the glycogen supercompensation in slow twitch muscle fibers. And a decrease in MRT of trained low CHO may be due to decreased glycogen contents of liver and muscles. The results also suggest that glycogen supercompensation was more evident in slow twitch red fibers of endurance-trained rats and blood glucose is one of the limiting factors of glycogen synthesis.

체력단련(體力鍛練)이 심전도파고(心電圖波高)와 QRS벡타에 미치는 효과(效果)

유완식(Yu, Wan-Sik),황수관(Hwang, Soo-Kwan),김형진(Kim, Hyeong-Jin),주영은(Choo, Young-Eun) 대한생리학회 1984 대한생리학회지 Vol.18 No.1

장기간(長期間) 체력단련(體力鍛鍊)이 심전도파고(心電圖波高) 및 심전도(心電圖) vector에 미치는 효과(效果)를 구명(究明)하고자 10명(名)의 운동선수군(運動選手群)과 13명(名)의 비운동선수군(非運動選手群)에서 rebounder운동전후(運動前後)의 심전도파고(心電圖波高)와 QRS vector의 길이를 측정(測定)하여 분절(分折)한 결과(結果)는 다음과 같다. 심전도파고(心電圖波高)에서 R파고(波高)는 선수군(選手群)이 23.38±1.14 mm로서 비선수군(非選手群)의 17.91±2.00 mm에 비(比)해 유의(有意)하게 높았고, 운동후(運動後)에도 선수군(選手群)이 계속(繼續) 유의(有意)하게 높았다. S파고(波高)는 양군(兩群) 모두 운동후(運動後)는 안정시(安靜時)에 비(比)해 유의(有意)하게 높았으며, T파고(波高)는 운동후(運動後) 감소(減少)하였다. P파고(波高)는 양군(兩群) 모두 운동후(運動後) 증가(增加)하였으며 선수군(選手群)이 다소 낮았다. PQ분절(分節)의 파고(波高)는 선수군(選手群)은 0인데 비(比)해 비선수군(非選手群)은 negative를 나타냈으며 운동후(運動後)에 유의(有意)하게 감소(減少)하였다. J점(點)은 양군(兩群) 모두 안정시(安靜時) positive에서 운동후(運動後) 유의(有意)하게 감소(減少)하여 negative를 나타냈고, J+0.08초(秒)도 운동후(運動後) 양군(兩群) 모두 감소(減少)하였으며 선수군(選手群)이 다소 높았다. 그러므로 ST분절(分節)은 운동후(運動後) 감소(減少)함을 알 수 있다. Rv₅와 Sv₁의 합(合)은 선수군(選手群)이 38.74±2.71 mm로서 비선수군(非選手群)의 32.28±2.90 mm에 비(比)해 높았으며 운동후(運動後)에도 선수군(選手群)이 유의(有意)하게 높았다. QRS vector 각도(角度)에서 Frontal plane에서 선수군(選手群)이 62.7±7.36˚로서 비선수군(非選手群)과 별(別) 차이(差異)가 없었고, horizontalplane에서는 선수군(選手群)이 -23.5±7.2˚로서 비선수군(非選手群)의 -38.8±8.2˚에 비(比)해 유의(有意)하게 높았으며 운동후(運動後) 양군(兩群) 모두 유의(有意)하게 높았다. QRS vector 길이에서 Frontal plane에서 선수군(選手群)이 13.86±1.44 mm로서 비선수군(非選手群)의 9.62±0.97 mm에 비(比)해 유의(有意)하게 높았으며 운동후(運動後)에도 유의(有意)하게 높았다. Horizontal plane에서도 선수군(選手群)이 19.82±2.10 mm로서 비선수군(非選手群)의 16.90±1.39 mm에 비(比)해 유의(有意)하게 높았고 운동후(運動後)에도 선수군(選手群)이 유의(有意)하게 높았다. 이상(以上)을 종합(綜合)해 보면 선수군(選手群)의 R파고(波高)가 비선수군(非選手群)에 비(比)해 운동후(運動後) 계속(繼續) 유의(有意)하게 높았고, Rv₅와 Sv₁파고(波高)의 합(合)이 38.74mm정도(程度)로 좌심실(左心室)이 비대(肥大)함을 알 수 있으며, 선수군(選手群)의 PQ분절파고(分節波高)와 ST분절(分節) 파고(波高)가 비선수군(非選手群)에 비(比)해 높고 운동후(運動後)에 양군(兩群) 모두 감소(減少)한 점(點)은 주목(注目)할만한 사실(事實)이며, 특(特)히 선수군(選手群)의 QRS vector의 길이가 모두 비선수군(非選手群)에 비(比)해 유의(有意)하게 긴점등(點等)으로 좌심실기능(左心室機能)이 우수(優秀)한 스포츠심장(心臟)임을 알 수 있으며, 선수군(選手群)과 비선수군(非選手群)을 평가(評價)할 수 있는 중요(重要)한 지표(指標)가 될 것으로 사료(思料)되는 바이다. In an effort to elucidate the effect of physical training on the electrocardiographic amplitudes, QRS vector, axis and QRS vector amplitude, electrocardiograms were recorded before and 1, 5 and 10 minutes after 3 minute rebounder exercise in 23 healthy male students aged between 18 and 21 years in two groups of athletes and non-athletes. ECG amplitudes were measured from lead I, V₁ and V₅ and axis and amplitudes of QRS vectors were measured from lead I and III in frontal plane, from lead V₂ and lead V₆ in horizontal plane. The results obtained are summarized as follows. ECG amplitudes: The R wave amplitude was 23.38±1.14 mm in athletes which was higher than 17.91±2.00 mm in non-athletes. After exercise, the difference in two groups remained significant throughout the recovery period. The S wave amplitude was increased significantly, and the T wave amplitude was decreased in both groups after exercise. The P wave amplitude was increased in both groups after exercise, and it was lower in athletes than in non-athletes. The PQ segment amplitude was zero in athletes but negative in non-athletes than in the resting state. The J point amplitude was positive in resting state and was negative after exercise in both groups. J+0.08 sec point amplitude was also lowered after exercise, and it was higher in athletes than in non-athletes. Therefore the whole ST segment was proved to be decreased after exercise. The summated amplitude of R in V₅ plus S in V₁ was 38.74±2.71 mm in athletes which was higher than 32.82±2.90 mm in non-athletes. After exercise, it was also significantly higher in athletes than in non-athletes. Axis of QRS vector: In frontal plane, axis of QRS vector was 62.7±7.36˚ in athletes, it showed no significant difference between the two groups. In horizontal plane, axis of QRS vector was -23.5±7.2˚ in athletes which was significantly higher than -38.8±8.2˚ in non-athletes. After exercise, it was significantly higher than the resting state in both groups. Amplitude of QRS vector : In frontal plane, amplitude of QRS vector was 13.86±1.44 mm in athletes which was significantly higher than 9.62±0.97 mm in non-athletes. After exercise, it was also significantly higher in athletes than in non-athletes. In horizontal plane, amplitude of QRS vector was 19.82±2.10 mm in athletes which was significantly higher than 16.90±1.39 mm in non-athletes. After exercise, it was also significantly higher in athletes than in non-athletes. From the above, these results indicate that R wave amplitude in athletes was significantly higher than in non-athletes before and after exercise, and that the summated amplitude of R in V₅ plus S in V₁ in athletes was also 38.74±2.71 mm suggesting a left ventricular hypertrophy We should note that the PQ segment and ST segment amplitude were higher in athletes than in non-athletes, and they were decreased with exercise in both groups. In particular, the fact that amplitudes of QRS vector in frontal plane or in horizontal plane were significantly greater in athletes than in non-athletes may be an index in evaluating athletes.