스포츠 심리학 : 트레드밀 운동과 Clenbuterol 투여가 쥐의 체지방 축적과 근효소의 활성에 미치는 영향

이민형(MinHyungLee),이수천(SooChunLee),강호율(HoYoulKang) 한국체육학회 1998 한국체육학회지 Vol.37 No.4

본 연구는 트레드밀 운동과 Clenbuterol(β₂-adrenergic agonist)의 장기간 투여, 그리고 두 가지를 복합하여 처치하였을 경우 체지방 함량과 근효소의 활성에 미치는 영향을 조사하는 것이 목적이다. 실험의 대상은 40마리의 SD(Sprague-Dawley)계 암컷 쥐(rat)로 하였으며, 무작위로 선정하여 각각 비처리군(CON), Clenbuterol 처리군(CL), 운동군(TR), 운동/Clenbuterol 처리군(TR+CL)으로 분리하였다. 훈련은 8%의 경사도로 동력으로 작동되는 treadmill을 이용하여 수행되었으며, 훈련기간은 주 5회 8주간 이루어졌다. Clenbuterol 투여방법은 물에 용해시킨 Clenbuterol을 1일 체중(kg)당 0.8mg씩 경구 투여하였다. 8주간의 운동트레이닝과 Clenbuterol투여는 집단간 성장률에는 유의한 변화가 없었다. 그리고 Clenbuterol투여와 트레이닝은 근육의 양을 유의하게 증가시켰으며, 체지방량은 유의하게 감소시켰다. 두 가지 처치의 복합적 영향은 근육 양의 증가에 있어서는 부가적이었으나, 체지방 양의 감소에 있어서는 부가적이지 않았다. 장기간의 Clenbuterol의 투여는 골격근에서 hexokinase와 citrate synthase활성의 유의한 감소를 가져왔다. 이와 같은 효소활성의 감소는 유의한 지구성 운동 수행력의 감소를 초래하였다. 그러므로, 본 연구의 결론은 체구성에 있어 Clenbuterol처치가 미치는 영향은 운동처치가 미치는 영향과 같으나, Clenbuterol투여와 운동처치는 각각 정상 쥐의 골격근 효소의 활성에 역으로 영향을 미치는 것으로 나타났다. The effects of exercise training, chronic administration of clenbuterol (β₂-adrenergic agonist), and the combination of these two treatments on body fat content and muscle enzyme activities were investigated. Forty male Sprague-Dawley rats were randomly assigned to one of four treatment groups: sedentary control (CON, clenbuterol (CL), exercise trained (TR), or exercise trained/clenbuterol (TR+CL). The training protocol consisted of running on a motor-driven treadmill up an 8% grade, 5 days/wk for 8 weeks. Rats receiving clenbuterol were intubated with 0.8 mg/kg body wt/day dissolved in deionized water. Exercise training and clenbuterol administration significantly not only reduced the body fat content as evidenced by the decreasing retroperitoneal fat weight, but also increased the skeletal muscle mass without the changes of growth rate. The combined effect of these two treatments in increasing the muscle mass was additive, but in reducing the fat content, it was not additive. Chronic clenbuterol treatment significantly reduced the hexokinase and citrate synthase activities in skeletal muscle. These decreased enzyme activities significantly reduced endurance performance. Thus, the results of the current study indicate that the effects of clenbuterol treatment are the same as the effects of exercise training in body composition, but each of the clenbuterol treatment and exercise training inversely affects the changes in skeletal muscle enzyme activities of normal rats.

축구 Instep Kick시 무릎 보호대가 하지근육활동에 미치는 영향에 비교분석

채원식(WoenSikChae),이민형(MinHyungLee) 한국체육학회 2002 한국체육학회지 Vol.41 No.2

본 연구의 목적은 축구 인스텝킥시 무릎보호대가 근육활동에 미치는 영향을 근전도 측정을 통해 비교 분석하는데 있다. 피험자의 동작을 분석하기 위해 한 대의 고감도 카메라가 (60 Hz, Panasonic AG455) 사용되었다. 근전도 측정을 위해 6벌의 전극을 피험자의 우측 하지 근육에 부착하였으며 측정 근육부위는 대퇴직근, 내측광근, 외측광근, 대퇴이두근 (단두), 전경골근, 외측 비복근을 대상으로 하였다. 근전도 측정치를 보다 정확하고 세밀하게 비교하기 위하여 인스텝킥 동작을 다음과 같이 두 단계로 구분하였다: (1) 스윙 (Swing) 단계 (왼쪽 발이 지면에 닿은 순간부터 오른발이 공에 닿을 순간까지); (2) 마무리 동작 (Follow-through) 단계 (오른발이 공에 닿은 순간이후부터 오른쪽 발이 가장 높은 위치에 있을 때까지). 축구 인스텝킥 동작시의 각 근육별 근전도 분석은 우선 측정치를 full-wave 정류한 후 최대 자율수축 근전도치로 나누어 표준화 한 다음 각 단계별 평균 및 최대 표준 근전도치를 계산하였다. 종속 t-test를 사용하여 무릎보호대 착용시와 비착용시의 차이점을 분석하였다. 분석 결과, 킥을 시작하는 순간과 발이 공에 닿는 순간 동안 대퇴직근, 내측광근, 외측광근, 외측 비복근의 활동이 높아짐을 알 수 있었고, 이 근육들은 모두 M자 모양의 근육활동 형태를 가지고 있었다. 대퇴이두근은 킥을 시작한 바로 후에만 근육활동을 보였다. 또한 전경골근은 발이 공에 닿기 바로 전에 가장 많은 근육활동을 보여주었다. 이 실험에서는 하지의 신전동작만 분석하였으므로 대퇴직근, 내측광근, 외측광근, 전경골근들이 대퇴이두근 (단두), 외측 비복근 보다 훨씬 높은 근육활동을 보여주었다. 두단계의 인스텝킥 동작시 가장 흥미로운 발견은 무릎보호대 착용과 함께 대퇴사두근의 근육활동이 현저하게 줄어들었고, 외측 비복근의 활동은 현저하게 높아졌다는데 있다. 이러한 결과는 두가지 이유로서 설명되어 질 수 있다. 외측 비복근은 무릎굴근이며 동시에 발목굴근이다. 두단계의 인스텝킥 동작시 무릎보호대에 의해 무릎은 완전히 펴지지 않게 되며 무릎의 굴근들이 보다 많은 근육활동을 보이게 된다. 그 결과, 킥동작이 끝날 때 까지 보다 많은 발목굴근들의 근육활동이 나타나게 된다. 이러한 결과들로서 특히 대퇴사두근과 관련지어, 무릎 보호와 지지라는 측면에서 무릎 보호대의 이점이 있다고 할 수 있다.

자연과학편 : 스트랭스화(靴)와 운동화(運動靴) 탄성충격저항(彈性衝擊抵抗)에 의한 Plyometric 트레이닝 효과비교(效果比較) 연구(硏究)

채홍원(HongWoenChae),이민형(MinHyungLee),장용수(YongSooChang),강영수(YoungSooKang),추계호(ZouJiHao),정후성(ZhenHouChen),원문학(WonMoonHeck) 한국체육학회 1995 한국체육학회지 Vol.34 No.1

It has been generally reported that. the plyometric training with volley-boll shoes(VS)can strengthen the voluntary muscles and improve their stetch reflex and the power in consequence of the connected elastic reflex: it provides an overloaded isometrics exercise which causes muscular stretch reflex in the amortization phase while players are engaging in landing and take-up motion.It is also generally argued that the plyometrics thaining with strength-power shoes(SPS) can reinforce the strength and power by overloading the muscles in thigh. calf and knee, and Achilles tendon: the strength-power shoes, with wide rubber soles and no heel, can shift and keep the whole body weight onto the front part of the feet. This research was intended to compare the SPS and the VS when they were employed in the plyometrics training by means of elastic impact resistance, and to determine which of the two would be better improve the muscular strength and power of the players. To attain the aim, we selected 24 university students in China, the non-controlled. group with ordinary VS. All the subjects were measured after training for 20 to 30 minutes on every third day for 8 weeks. With other training conditions equal, both groups were assigned with. the gradual loading system of plyometric exercise: that is, with the increasing height of the springboard form 40cm to 50, 60, and 70cm for the subjects to experience the repetitive isometric stress. Every record was measured before and after the test with cross-sectional analysis.The result of which are as follows.1. Motor FitnessThe SPS group showed a higher performence rate in motor speed(1), vertical jump(6), and power(1). The improvement rates in the pre-post test of SPS and VS were, respectively, 68% and 5.9%. 16.8% and 10.2%, 17.3% and 15.9%, 21.4% and 15.6%, 22.9% and 21.4%, 22.3% and 17.5% and 23.7% and 17.8%(p<0.01)In the improvement rate, SPS showed a higher rate(15.7%, 16.3%, 12.6%, 17.2%, 0.1%)than VS, and the level of 5% in vertical jump was statistically significant whole other factors were not.2. Motor Impact ForceIn motor impact force Fz, Fxyz, Fmax, and APT, the recorded performence were similsr, but in the amortization phase, the SPS group recorded a better result. The rates in the pre-post test of SPS and VS were 43.4% and 27.7%, 43.1% and 26.8%, 36.9% and 24.3%, 22.3% and 51% and 12.3 and 12.2 and respectively(p<0.01, p< 0.05).The differences of the improvement rate between the two groups were measured as 15.7%, 16.3%, 12.6%, 17.2% and 0.1% in favor of the SPS group, but statistically they were insignificant with the level of only 5%. (p >0.05%).3. SuggestionSince the SPS group showed a higher performance rate in the gradual plyometrics training for the period of 8 weeks, we are confident that such training method would be very effective for motor speed, power, and impact force. And we sincerely hope that the method we have explored would be adopted as frequently as the explosive jump training which have been so far perferred in training.Finally we can say with some special emphasis that our exploration can be made into an Super Quality Training program for more effective training in the items which require a high degree of speed and jumping ability such as volley ball, basketball, soccer and hurdle race.

운동역학 : 등속성 운동 시 스포츠 테이핑이 하지 근육 활동에 미치는 영향

김연정(YounJoungKim),채원식(WonSikChae),이민형(MinHyungLee) 한국체육학회 2004 한국체육학회지 Vol.43 No.5

This study compared EMG activities between quadriceps and hamstrings with taping and without taping during isokinetic exercise. For this experimentation, Eight healthy male and female university students performed knee extension and flexion at 180°/s for experimentation, and isometric action at 90° for MVIC(maximam voluntary isometric contraction). Cybex(Cybex340) was used for isokinetic exercise and its statistical analysis was done by paired t-test. After surface electrodes were attached to rectus femoris, vastus medialis, vastus laterlis, biceps femoris, and serrdtendinosus, averaged EMG and Peak EMG, with taping and without taping, were measured. There were no significant mucsles EMG activities between with taping and without taping except rectus femoris during flexion and biceps femoris during extension The EMG signals of rectus femoris in flexion and biceps femoris in extention were significantly reduced with taping. EMG activities were generally decreased after taping when we examine the whole patterns of data This seems to be due to the fact that by sustaining the vector direction of the muscles, sports taping makes it possible to do an exercise of the same load with just a little activity of muscles. Because the muscles which showed significant statistical differences were all antagonist, we think the taping took the stability supporting role of antagonist, so that EMG activities were reduced. And another possible reason is that it seems to be related to proprioception that manages extension of muscles.