비만을 동반한 폐경이 Group 구심성 신경의 대사적 수용기에 미치는 영향

김지연(Ji-Yeun, Kim),김종경(Hosung Nho),노호성(Jong-Kyung Kim),장명재(Myoung Jei Chang) 한국생활환경학회 2012 한국생활환경학회지 Vol.19 No.6

Both obesity and menopause cause the dysfunction of autonomic nervous system. Recent human studies have reported that exercise pressor reflex (EPR)-mediated increases in blood pressure are exaggerated in obese or postmenopausal women. Whether these findings can be extended to both obese and postmenopausal women remains unclear. Mean arterial pressure (MAP), cardiac output (CO), and total vascular conductances (TVC) were measured in normal premenopausal women (NPW; n = 11; 36 ± 2 yr), normal postmenopausal women (NPOW; n = 14; 57 ± 1 yr), and overweight postmenopausal women (OPOW; n = 14; 56 ± 1 yr) at baseline, and during static handgrip at 50% maximal voluntary contraction (MVC) followed by a period of postexercise muscular ischemia (PEMI) to isolate the metabolic component of the EPR. Changes in MAP from baseline were augmented in OPOW subjects during both 50% MVC handgrip (P < 0.05), and these group differences were maintained during PEI (P < 0.05). There were no differences in heart rate (HR), stroke volume (SV), and CO during hand grip exercise and PEMI among groups. Even though there was no group difference in TVC during exercise and PEMI, the TVC tended to be abolished in OPOW group. In summary, compared with NPW subjects, OPOW group exhibit exaggerated pressor responses to handgrip exercise that are maintained during PEMI, indicating that activation of the metabolic component of the EPR is augmented in OPOW group. The exaggerated pressor response mediated by the muscle metaboreflex activation in OPOW group mainly occurs via preperial vasoconstriction with little change in CO.

정상혈압자의 Beetroot 섭취가 정적운동 시 Group IV 대사적 수용기에 미치는 영향

김경애(Kyung Ae Kim),최현민(Hyun Min Choi),김종경(Jong Kyung Kim),노호성(Hosung Nho) 한국발육발달학회 2015 한국발육발달학회지 Vol.23 No.2

It is reported that beetroot juice supplementation reduces blood pressure in healthy subjects at rest. It is not known that beetroot juice supplementation alters the pressor response mediated during exercise and by the muscle metaboreflex activation in normotensive. Thus, the purpose of this study was to investigate the effects of dietary nitrate derived from beetroot on muscle metaboreflex in normotensive compared with placebo. Fifteen normotensive (22.7±0.5 yrs) were recruited in this study. All subjects were assigned in a randomized, double-blind, crossover design to receive beetroot (70 mL/day, ~5.6 mmol of NO₃ -) and placebo (70 mL/day, no NO₃ -) for 15 days. The subjects completed 2 min static handgrip exercise at 50% maximal voluntary contraction followed immediately by post exercise muscle ischemia(PEMI). On day 15, the same protocol was repeated after beetroot or placebo supplementation. All subjects were continuously instrumented to measure heart rate (HR), stroke volume (SV), and obtain cardiac output (CO), mean arterial pressure (MAP), total peripheral resistance (TPR) at rest and during static exercise and PEMI. Compared with beetroot, placebo significantly decreased resting MAP (2.5±1.7 vs. -1.1±1.7 mmHg) and during exercise HR (5.4±2.2 vs. 2.6±2.6 beats/min). There were no difference in SV, CO and TPR between beetroot and placebo at rest and during static exercise and muscle metaboreflex activation. Thus, this study indicates that beetroot juice supplementation reduce MAP at rest, while no effects on muscle metaboreflex. Therefore, this study suggests that beetroot diet are regarded as healthy and associated with low incidence of cardiovascular disease in normotensive.

Cardiovascular Responses to Exercise during Acute Nicotine Abstinence

Sun-Kyu Lee(이선규),Hyun-Min Choi(최현민),Jong-Kyung Kim(김종경),Chan-Ho Kim(김찬호),Hosung Nho(노호성) 한국생명과학회 2012 생명과학회지 Vol.22 No.4

흡연자의 단시간의 흡연 중단이 안정 시 및 저강도(40% of VO2max), 중강도(60% of VO2max)에서의 일회성 유산소성 운동 중에 나타내는 심혈관 반응의 차이를 알아보는데 있다. 따라서 성인 남성 흡연자를 대상으로 흡연직후, 흡연 중단 24시간과 흡연 중단 48시간 경과 후의 안정 시, 저강도, 중강도의 강도별 사이클 에르고미터를 통한 일회성 유산소 운동 시 심혈관계 반응을 검토하였다. 이에 따른 결과 흡연 직후, 흡연 중단 24시간과 흡연중단 48시간 경과 후의 안정 시, 저강도, 중강도의 수준의 운동 강도별 사이클 에르고미터를 통한 일회성 유산소운동 시 SBP, DBP, MAP, HR에서 유의한 감소가 나타났다(p<0.05). 또한, 안정 시와 중강도에서는 CO의 유의한 감소가 나타났다(p<0.05). 이상의 결과로부터 단시간의 흡연 중단은 교감신경의 항진상태를 완화시키고, 부교감신경계의 활성화로 인해 HR을 감소시킴으로써 안정 시와 동일 강도 유산소운동 시의 과도한 심혈관 반응을 완화키는 것으로 사료된다. 이를 통해 흡연자에게 있어 단기간의 흡연 금지만으로도 운동 중에 심혈관계 반응의 위험을 감소시킬 수 있다는 가능성을 나타냈다. We investigated the effect of smoking on cardiovascular responses during acute dynamic exercise. Eleven college students who had been smoking (duration of smoking: 7.45±0.90 years; number of cigarettes per day: 17.72±1.22) participated in this study. All subjects completed a graded exercise testing to determine the relative exercise intensity. The cardiovascular responses were measured at rest, and during mild and moderate exercise immediately, 24, and 48 hours after smoking. The same procedures were repeated during 24-h smoking withdrawal. All subjects were continuously instrumented to measure systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV), cardiac output (CO), and total vascular conductance (TVC) at rest and during exercise. The results showed that compared to the nicotine abstention, SBP, DBP, MAP, and HR were significantly higher at 24 and 48 hours after smoking (p<0.05), and CO was significantly higher at rest and during moderate exercise (p<0.05). There were no differences in SV and TVC before and after smoking. Thus, the results suggest that smoking is associated with an exaggerated sympathetic nerve activity during dynamic exercise. Consequently, smoking cessation may help reduce cardiac events, such as stroke and heart attack, during exercise.

설문지를 이용한 신체활동량과 참여강도가 중년여성의 체력 및 관상동맥 위험인자에 미치는 영향

안영환(Young Hwan An),박세정(Saejong Park),최현민(Hyun Min Choi),김종경(Jong Kyung Kim),노호성(Hosung Nho) 한국발육발달학회 2015 한국발육발달학회지 Vol.23 No.1

The purpose of the study was to investigate the effects of the volume of physical activity on obesity, physical fitness and coronary risk factors among the middle-aged women. physical activity was assessed from International Physical Activity Questionnaire (IPAQ) and were categorized by health enhancing physical activity group (PG), minimum activity group (MG), and non-activity group (NG) according to the volume of physical activity. Apparently healthy middle-aged women (n=163; 52.1±8.6 yrs) participated and they were classified as PG (n=46; 5,878±3547 MET·min/week), MG (n=64; 1,678±886 MET·min/week), and NG (n=52; 456±389 MET·min/week). Also, method of the study was categorized by vigorous activity and moderate activity according to the study of WHO (2010) and Mikael Fogeholm (2006). Measurement variables were body composition, physical fitness (hand-grip, sit-up, pacer, sit & reach, shuttle run, and long jump), total cholesterol (TC), low-density lipoprotein cholesterol (LDLC), high-density lipoprotein cholesterol (HDLC), and triglycerides (TG). One-way ANOVA was used with Tukey post-hoc (p<.05). In the result, PG had significantly low percent body fat comparing with MG or NG (p=.02). And, among physical fitness variables flexibility was higher in PG than in MG (p=.03). While HDLC (p=.007) was higher in the PG than MG or NG, LDLC (p=.024) was lower in the PG than MG. TG (p=.021) was lower in the PG than MG or NG. Vigorous activity group had significantly high pacer in classification as physical activity intensity. Glucose was lower in vigorous activity group than in moderate activity group (p=.02). In conclusion, it was generally low body fat rate and coronary risk factors for middle-aged women to increased volume of physical activity of daily life and participating vigorous activity indicated that was able to keep a high fitness standard.

Beetroot 섭취가 경계성 고혈압자의 GroupIV 대사적 수용기에 미치는 영향

김보희(Bo Hee Kim),최현민(Hyun Min Choi),노호성(Hosung Nho),김경애(Kyung Ae Kim),정은지(Eun Ji Jung),김종경(Jong Kyung Kim) 한국발육발달학회 2014 한국발육발달학회지 Vol.22 No.3

It is reported that beetroot juice supplementation reduces blood pressure in healthy subjects at rest. However, It is not known that beetroot juice supplementation alters the pressor response mediated during exercise and by the muscle metaboreflex activation in prehypertension. Thus, the purpose of this study was to investigate the effects of dietary nitrate derived from beetroot (BR) on muscle metaboreflex and endothelial function in prehypertension compared with placebo (PR). Eleven prehypertensives (24±2 yrs) were recruited in this study. All subjects were assigned in a randomized, double-blind, crossover design to receive BR (70 mL/ day, ~5.6 mmol of NO3 -and PL (70 mL/day, no NO3 -) for 15 days. The subjects completed 2 min static handgrip exercise at 50% maximal voluntary contraction followed immediately by post exercise muscle ischemia(PEMI). On day 15, the same protocol was repeated after BR or PL supplementation. All subjects were continuously instrumented to measure heart rate, stroke volume, systolic blood pressure (SBP), diastolic blood pressure (DBP), and obtain cardiac output(CO), mean arterial pressure(MAP), total peripheral resistance (TPR) at rest and during static exercise and PEMI. Compared with PL, BR significantly increased resting plasma nitrate/nitrite (NOx) concentration (PL: 147.8±10.3 vs. BR: 193.7±19.2, p <.05) and decreased SBP (133±1 vs 128±2 mmHg, p <.05). Normalized flow mediated dilation (FMD) was significantly increased (BR: 2.24±0.3 vs PL: 1.86±0.2, p <.05). There were no differences in CO, MAP, and TPR between BR and PL at rest and during static exercise and muscle metaboreflex activation. Thus, this study indicates that beetroot juice supplementation improves the endothelium function and reduce blood pressure at rest, while no effects on muscle metaboreflex. Therefore, this study suggests that BR diet are regarded as healthy and associated with low incidence of cardiovascular disease in prehypertention.

3주간의 녹용분말 복용이 신장성운동 후 유발된 근 손상 예방 및 회복에 미치는 효과

정영근(Young-Geun Jung),최현민(Hyun-Min Choi),김종경(Jong-Kyung Kim),노호성(Hosung Nho) 한국생활환경학회 2009 한국생활환경학회지 Vol.16 No.3

Eccentric exercise damaged the skeletal muscle, causing soreness, swelling, tenderness. Exercise induced muscle damage (EIMD) increases possibility of injury and decreases performance of eccentric exercise. Previous studies have been interested in measuring and improving recovery of EIMD, but there have been controversial results. Therefore, the purpose of this study was to investigate the effects of the Cervus elaphus (deer velvet) on recovery of EIMD after eccentric exercise. Twenty female college students participated in this study. Subjects were divided into two groups (Cervus elaphus group and placebo group). The subjects were randomly assigned to either Cervus elaphus group (n=10) or placebo group (n=10). Each group received either Cervus elphus powder (2000 ㎎/day) or placebo capsule (2000 ㎎/day) for 14 days, and then for 7 days after eccentric exercise. For Eccentric exercise knee extensors and flexors were performed by isokinetic dynamometer (Cybex 770) on 15th day, 50 times, 3 sets. CK, GOT, Myglobin and VAS were measured right before eccentric exercise and at first, second, seventh day during recovery. CK and GOT were significantly increased in placebo group after eccentric exercise, while there were no differences in CK, GOT, myoglobin, and VAS between tow groups across the times. It is concluded that Cervus elphus may be effective to reduce muscle damages and improve recovery from eccentric exercise. Further study about functional change after eccentric exercise with a dose of Cervus elphus is needed in the future.

유산소운동이 중년 비만여성의 대사적 수용기 자극에 따른 심혈관 반응에 미치는 영향

한우람(Woo-Ram Han),최현민(Hyun-Min Choi),노호성(Hosung Nho),김종경(Jong-Kyung Kim) 한국생활환경학회 2011 한국생활환경학회지 Vol.18 No.4

The purpose of this study was to investigate whether aerobic exercise training improves the muscle metaboreflex in obese women. Eight obese women were recruited in this study. Subjects performed 3 min static handgrip exercise and 2 min of post exercise muscular ischemia (PEMI) while heart rate (HR), stroke volume (SV), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were measured followed by the calculation of cardiac output, mean arterial pressure (MAP), and total vascular conductance (TVC). All subjects completed 12 wk aerobic exercise training consisting of 3 times/wk and 40 min per session. Subjects walked/ran at the exercise intensity of 50% maximum heart rate on the treadmill. In order to maintain the target heart rate, the speed and grade were manipulated every two weeks. With aerobic exercise training, SBP, DBP and MAP were significantly decreased during static exercise, while TVC was significantly increased. Both SBP and MAP responses mediated by the muscle metaboreflex were significantly decreased. These results indicate that aerobic exercise training altered the strength of the muscle metaboreflex. Thus, regular aerobic exercise training may improve impaired peripheral vasoconstriction and exaggerated blood pressure response induced by the muscle metaboreflex in obese women.

고혈압 전단계 여성에 대한 골격근 group Ⅲ 기계적 수용기 자극 시 심혈관에 미치는 영향

박승애(Seung-Ae Park),최현민(Hyun-Min Choi),유승희(Seung-Hee Yoo),박태웅(Tae-Woong Park),노호성(Hosung Nho),이홍열(Hong-Youl Lee),김종경(Jong-Kyung Kim) 한국생활환경학회 2010 한국생활환경학회지 Vol.17 No.1

It was suggested that the exercise pressor reflex (EPR) plays an important role to regulate the cardiovascular responses during dynamic exercise. A component of EPR, group Ⅲ mechanoreceptors evoked excessive blood pressure response in hypertensive rats during passive tendon stretch. But it is not known that this exaggerated blood pressure response to passive tendon stretch is mediated by EPR overactivity in prehypertensive women. Therefore, this study was to investigate the physiological responses in both normotension and prehypertension during passive tendon stretch. Twenty subjects (10 prehypertension and 10 normotension) with a mean age 49.0±3.4 years were recruited for this study. All subjects were continuously instrumented to measure stroke volume (SV), heart rate (HR), cardiac output (CO), total vascular conductance (TVC) throughout the experiment. To stimulate the group Ⅲ mechanoreceptors, brief passive dorsiflexion of the foot was performed by a cybex for one minute. The results showed that mean arterial blood pressure was significantly increased during dorsiflexion in both groups, however, this pressor response was significantly higher in prehypertensive women. SV and CO were significantly increased in normotensive women, while there were no differences in prehyperentsive women. There was no difference in HR in both groups. TVC was significantly decreased in prehypertension, while no difference in normotension. It is concluded that the excessive pressor response mediated by dorsiflexion is occurred by overactivity of group Ⅲ mechanorecptors and the mechanism is produced via mainly peripheral vasoconstriction in prehypertensive women.

고혈압 남성의 점증적 유산소운동 실시에 따른 심혈관 반응

황미진(Mi-Jin Hwang),최현민(Hyun-Min Choi),김경애(Kyung-Ae Kim),노호성(Hosung Nho),김종경(Jong-Kyung Kim) 한국생활환경학회 2014 한국생활환경학회지 Vol.21 No.6

The purpose of this study was to investigate physiologic response during dynamic exercise in the people with normotension, prehypertension, and hypertension. Thirty males (12 normotensive, 9 prehypertensive, and 9 hypertensives) were recruited in this study. To determine relative exercise intensity, all subjects completed maximal cycling exercise test and then performed two submaximal testing at the intensity of 40% and 60% VO2max. Subjects were instrumented to measure the cardiovascular responses by non-invasive method through the experiment. Heart rate (HR), stroke volume (SV), and cardiac output (CO) were measured by Physio Flow and blood pressure was measured by mercury sphygmomanometer from the brachial artery. The results indicate that excessive response in blood pressure was found in the both prehypertensives and hypertensives with increasing exercise intensiy compared to normotensives, and the hypertensives had a significantly higher blood pressure compared to prehypertensives. Both prehypertension and hypertension had significantly higher CO during dynamic exercise compared to normotension. The CO response also tended to be higher in hypertensives compared to the prehypertensives. Total vascular conductances (TVC) were significantly increased in three groups as the exercise intensity increased, but there were no significant differences between groups. Thus, the excessive pressor response in both prehypertension and hypertension during dynamic exercise is mediated by an increase in CO despite little change in TVC. This study suggests that the strategies to treat excessive cardiac output response may prevent an exaggerated blood pressure response during dynamic exercise in both prehypertension and hypertension.

대학 축구선수의 항산화 물질 정맥투여가 근 손상 회복능력 및 실험관 반응에 미치는 영향

곽정자(Jung-Ja Kwak),최현민(Hyun-Min Choi),김효철(Hyo-Chul Kim),정재우(Jae-Woo Chung),김종경(Jong-Kyung Kim),노호성(Hosung Nho) 한국생활환경학회 2012 한국생활환경학회지 Vol.19 No.2

This study was designed to investigate cardiovascular responses and the recovery from muscle damage after the anti-aging intravenous therapy (AAIT) (once in 2 days, total 14 treatments) in 10 college soccer players. The hemodynamic responses and muscle damage fatigue factors were assessed before and after the AAIT treatment. Muscle damage was induced with 50 min downhill running at the intensity of 75% of VO₂max). The cardiovascular responses were measured by a non-invasive device Physio flow during exercise. After the treatment, There were no statistical differences in the levels of both La and VO₂max levels, while the rapid recovery occurred in the level of the GOT, CK, and ammonia compared to before the treatment (from 30.1±3.01 to 23.7±2.22 U/L; from 277±36.92 U/L to 174.2±40.8 U/L; 113.0±6.13 ug/dL to 75.2±2.92 ug/dL, respectively). Total vascular conductance, stroke volume, and cardiac output were significantly improved after the MIT treatment. Thus, the results indicated that the AAIT treatment may increase oxygen delivery to active skeletal muscle and improve the recovery from muscle damage. Our study suggests that the AAIT treatment could enhance exercise performance and intervene muscle damage in athletes during intense exercise.