• 한방재활의학과학회지
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• 제19권2호
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• pp.241-250
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• 2009

Objectives : To study autonomic nervous system dysfunction of Low Back Pain(LBP) patients, using spectral analysis of Heart Rate Variability(HRV). Methods : HRV of 190 patients was measured and seperated into two groups, those with LBP(n=95) and healthy controls(n=95). HRV was measured by SA-6000(Medicore, Korea) for 5 minutes after 5 minutes' resting. Results : 1. Mean heart rate(MHRT) of the experimental group was slightly higher than that of the control group, but did not show significant difference(P=0.428). The square root of the mean squared differences of successive normal-to-normal intervals(RMSSD), logarithmic very low frequency power(Ln VLF) and low frequency power/high frequency power ratio(LH/HF ratio) were not significantly low between experimental group and control group(P=0.16, 0.130, 0.537). 2. The standard deviation of all the normal-to-normal intervals(SDNN), logarithmic total power(Ln TP), logarithmic low frequency power(Ln LF) and logarithmic high frequency power(Ln HF) were significantly low between experimental group and control group(P=0.03, 0.005, 0.001, 0.007). 3. Ln LF of acute group was significantly low compared with those of chronic group(P= 0.039). Conclusions : This study suggests the activity and imbalance of autonomic nervous system in LBP is low. Also sympathetic nervous system of acute LBP is lower than that of chronic LBP. Further study of HRV related to LBP is needed in the clinical medicine.

• 대한의용생체공학회:의공학회지
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• 제18권3호
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• pp.285-290
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• 1997

In this paper, the power spectral analysis and the fractal analysis of heart rate variability(HRV) were performed to evaluate the effects of brain lesion on cardiovascular system and autonomic function for 24 normal subjects and 22 hemiplegic patients. The ECG and respiration signals were recorded at tilt angles of $0^{\circ}$ and $70^{\circ}$ for 5 and 6 minutes successively under the condition of frequency controlled respiration (0.25Hz). For normal subjects, HR, LF component, HF component and fractral dimension of HRV were distinctly changed after orthostatic stress, whereas, for hemiplegic patients, those were little changed. Complexity and variability of heart rate of patients were smaller than those of normal subjects. Sympathetic tone of patients was higher than that in normal subjects. All of these results support that autonomic disorder and cardiovascular disturbance accompanied by brain lesion could be assessed by the power spectral analysis and fractal analysis of HRV.

• 한국한의학연구원논문집
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• 제17권2호
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• pp.85-100
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• 2011

Objectives : This study aimed to investigate the effect of four common types of Qigong position (standing, sitting, supine, and horse-riding position) on the autonomic nervous system. Method : Thirty healthy subjects participated in this study once a week for four weeks. Heart Rate Variability (HRV) was measured three times (before, during, and after the position) while the subject maintained one of four positions for ten minutes. Result : There were significant changes HRV in the standing position. In the sitting position, both the sympathetic and parasympathetic nerves were activated. On the other hand, in the spine position, heart rate (HR) was decreased. Activation of sympathetic and parasympathetic nerves was also observed in this position. Significant increases of indices related to awakening and concentration were observed accompanied by increase of HR and a sympathetic nerve was activated in the riding-horse position. Conclusions : In the present study, it was shown that each Qigong position caused various and significant changes in autonomic nervous system. It would be expected that these results can be applied to choose appropriate Qigong position according to objective of Qigong therapy although it is remained to further evaluate the effects of long-term maintenance of Qigong positions and repeated Qigong training.

• Animal Bioscience
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• 제37권5호
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• pp.944-951
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• 2024

Objective: Parturition is crucial for dams, their calves, and cow managers. The prediction of calving time, which assists cow managers to decide on the relocation of cows to maternity pens and necessity of human supervision, is a pivotal aspect of livestock farming. However, existing methods of predicting calving time in dairy cows based on hormonal changes and clinical symptoms are time-consuming and yield unreliable predictions. Accordingly, we investigated whether heart rate variability (HRV) which is a non-invasive assessment of autonomic nervous system (ANS) activity and behavior during the prepartum period would be useful for predicting calving time in dairy cows. Methods: Eight pregnant cows were surveilled under electrocardiogram and video recordings for HRV and behavioral analyses, respectively. HRV parameters in time and frequency domains were evaluated. A 24-h time budget was calculated for each of six types of behavior (standing and lying with or without rumination, sleeping, and eating). Results: Heart rate on calving day is considerably higher than those recorded on the days preceding calving. Low frequency power declined, whereas high frequency power escalated on the calving day compared to the period between 24 and 48 h before calving. The time budget for ruminating while lying decreased and that while standing increased markedly on the calving day compared to those allocated on the preceding days; nonetheless, the total time budget for ruminating did not differ during the prepartum period. Conclusion: We elucidated the ANS activity and behavioral profiles during prepartum period. Our results confirm that HRV parameters and behavior are useful for predicting calving time, and interestingly indicate that the time budget for ruminating while standing (or lying) may serve as a valuable predictor of calving. Collectively, our findings lay the foundation for future investigations to determine other potential predictors and formulate an algorithm for predicting calving time.

• The Korean Journal of Physiology
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• 제30권1호
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• pp.43-51
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• 1996

This study was aimed to elucidate the changes in heart rate variability during treadmill exercise at various speeds and grades by spectral analysis. Thirty-three untrained male college students aged $20{\sim}26\;yr $were employed to exercise on a treadmill using 4 speeds (4.02, 5.47, 6.76 and 8.05 km/h) and 6 grades (0, 4, 8, 12, 16 and 20%). A fixed speed was selected for each session with the grade increased every 3 min. The electrocardiogram, respiration and the stepping activity were continuously recorded through an A/D converter system on the computer disk. Power spectra of heart rate variability (RRV) were obtained by use of a fast Fourier transform algorithm. The frequency domain was divided into 3 bands: $VLF\;(0{\sim}0.04\;Hz),\;LF\;(0.04 {\sim}0.15\;Hz)\;and\;HF\;(0.15{\sim}1.00\;Hz).$ Heart rate was $74.4{\pm}2.1\;beats/min$ at rest and showed a steady increase during treadmill exercise with increasing speed and grade up to $196.7{\pm}5.0\;beats/min.$ Total power of HRV was $35.0{\pm}6.7\;(beats/min)^{2}$ at rest and progressively decreased during exercise down to $1.9{\pm}0.3\;(beats/min)^{2}.$ The %VLF power of HRV was $34.5{\pm}3.7\; %$ at rest and showed no significant change during exercise except for a decrease observed at the highest intensity of exercise. The %LF power was $44.1{\pm}3.0\;%$ at rest and showed a progressive decrease down to $4.5{\pm}1.0\;%$ during those stages of exercise where heart rate was over 135 beats/min. The %HF power was $21.4{\pm}2.9\;%$ at rest and showed a progressive increase up to $87.1{\pm}6.7\;%$ during higher intensity exercise where heart rate was over 165 beats/min. Peak frequency of HF band was $0.200{\pm}0.018\;Hz$ at rest and was shifted to higher frequencies up to $0.909{\pm}0.048\;Hz$ at heart rates greater than 135 beats/min. Respiratory frequency was $18.0{\pm}1.5$ breaths/min at rest and significantly increased during exercise up to $53.0{\pm}3.7$ breaths/min. Stride frequency during treadmill exercise showed an increasing tendency with increasing speed from $55.6{\pm}0.9$ steps/min at 4.02 km/h to $81.2{\pm}0.6$ at 8.05 km/h. It was concluded that total power of HRV decreased progressively with increasing exercise intensity due to the withdrawal of parasympathetic activity. At higher exercise intensity, % LF power decreased and %HF power increased with its peak frequency shifted to higher values in a progressive mode with increasing speed and grade, reflecting a readjustment in the cardiovascular system and the increased respiration and its rate, respectively.

• Journal of Electrical Engineering and Technology
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• 제3권4호
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• pp.576-583
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• 2008

In this study, we attempt to design a real-time autonomic nervous system(ANS) evaluation system usable during exercise using heart instantaneous frequency(HIF). Although heart rate variability(HRV) is considered to be a representative signal widely used ANS evaluation system, the R-peak detection process must be included to obtain an HRV signal, which involves a high sampling frequency and interpolation process. In particular, it cannot accurately evaluate the ANS using HRV signals during exercise because it is difficult to detect the R-peak of electrocardiogram(ECG) signals with exposure to many noises during exercise. Therefore, in this study, we develop the ground for a system that can analyze an ANS in real-time by using the HIF signal circumventing the problem of the HRV signal during exercise. First, we compare the HRV and HIF signals in order to prove that the HIF signal is more efficient for ANS analysis than HRV signals during exercise. Further, we performed real-time ANS analysis using HIF and confirmed that the exerciser's ANS variation experiences massive surges at points of acceleration and deceleration of the treadmill(similar to HRV).

• 셀메드
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• 제5권1호
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• pp.4.1-4.4
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• 2015

Yoga is an ancient Indian system of life, encompassing various practices including practices for self-discipline and also for regulating the health states of the individual, being practiced for thousands of years. The present study aims at understanding the effect of two high frequency breathing practices over autonomic nervous system. Forty healthy male volunteers of age $21{\pm}2$ years with $9{\pm}3$ months of Yoga practice experience were recruited. The two high frequency Yoga breathing practices, kapalabhati (KB) and bhastrika (BH) were given as interventions randomly on either of the two days to minimise laboratory bias. They were assessed before and immediately after the interventions for heart rate, respiratory rate, heart rate variability (HRV), blood pressure and peripheral oxygen saturation. There was a significant increase in heart rate (p<0.01; p<0.001), systolic blood pressure (p<0.01; p<0.001), NN50 (p<0.01; p<0.001) component of HRV for both KB and BH groups respectively. There was a significant reduction in respiratory rate in both the groups (p<0.001, and p<0.05, BH and KB respectively) immediately following intervention. A significant increase in LF component of HRV and reduction in Diastolic blood pressure and high frequency (HF)component following KB was also observed (p<0.05, for all comparisons). The Mean peripheral oxygen saturation remained unaltered in both the groups (p>0.05).The results suggest that high frequency yoga breathing practices induce physiological arousal immediately as evidenced by increased blood pressure and heart rate. The sympathetic arousal was more following KB session as evidenced by an increased diastolic blood pressure, LF power and a decrease in HF power of HRV as compared to the BH session.

• 대한한의진단학회지
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• 제11권1호
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• pp.146-156
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• 2007

1. The effect of variations in inspiration and expiration times on heart rate variability was studied in 78 healthy subjects (mean age $24.35{\pm}1.92$ years; 47 male) between regulated respiration group and normal respiration group as the control group. 2. The control group followed normal respiration pattern, whereas the regulated group followed three types of respiration pattern. The first pattern was long respiration(E/I ratio 1.6:1), the second pattern was short inspiration followed by long expiration (SILE), and the last pattern was long inspiration followed by short expiration(LISE). The average expiration/inspiration time ratios of SILE and LISE were 1.0 and 3.4, respectively. The respiration rate in the regulated group was approximately 10 cycles/min. 3. Respiration rate and tidal volume are respiratory variables known to modulate RSA. The results of the present study indicate that RSA can also be modulated by a third respiratory variable, the expiration/inspiratory time ratio. In this study, LF, HF, RSA, VLF is increased the most in LISE group compared to the other groups. HF and RSA increased significantly in the long respiration rate and SILE groups. However LF and VLF, which reflects the sympathetic tones, did not increase as much as the LISE group.

• 대한한방내과학회지
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• 제43권1호
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• pp.53-67
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• 2022

Objectives: This study aimed to identify the characteristics of the heart rate variability (HRV) index in patients with burning mouth syndrome (BMS) and to evaluate the predictive value of HRV for Korean medical treatment responsiveness to tongue pain in BMS. Methods: Among BMS patients who visited the Oral Diseases Clinic of Kyung Hee University Korean Medicine Hospital from January 1, 2018, to May 31, 2021, we reviewed the clinical records of 217 women aged 50 years and over. HRV and unstimulated saliva flow rate (USFR) measurements were carried out, and all patients were asked to indicate their degree of tongue pain using the visual analog scale (VAS). The subjects were classified into subgroups according to the presence or absence of hyposalivation and VAS improvement, and each subgroup was compared using the HRV index. Logistic regression analysis was conducted to confirm whether cause-effect relationships were present between statistically significant values. Results: BMS patients had lower LF and HF than healthy people. Subgroup analysis demonstrated that there were some statistically significant differences in the HRV index according to salivation rate and degree of pain. In addition, as the LF/HF ratio increased, the pain improvement rate decreased after treatment. Conclusion: The autonomic nerve activity of BMS patients was lower than that of healthy people; however, autonomic balance was not impaired. In addition, tongue pain in BMS patients responded more favorably to Korean medical treatment when patients fell within a normal range of the LF/HF ratio, suggesting that autonomic imbalance could be used as one of the predictable factors in clinical practice.

• 감성과학
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• 제8권2호
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• pp.95-101
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• 2005

본 연구는 관상동맥 질환(coronary artery disease : CAD) 환자의 심장 부교감신경 활성화가 감소하고, 만성 심부전(chronic heart failure : CHF) 환자의 심박동변이도(heart rate variability : HRV)에서 정상적 RR 간격의 분산(SDNN : standard deviation of all normal RR intervals)과 저주파수 대역의 전력스펙트럼(low-frequency power : LF),그리고 복잡성이 감소하며, CAD환자의 우측으로 누운 자세에서 HRV의 규격화된 고주파수대역의 전력스펙트럼(normalized high-frequency power : nHF)가 3가지 누운 자세 중에서 가장 높다는 사전 정보에 근거하였다. 세 가지 누운 자세에 대한 HRV의 비선형 특징은 알려진 바가 없으므로, 본 연구에서는 관상동맥질환 환자들을 대상으로 누운 자세에서 HRV의 선형과 비선형특성을 조사하였다. 이 목적을 위하여, 관상동맥질환군 29명과 통제군 23명을 대상으로 세 가지 누운 자세에서 심전도의 Lead II 채널을 측정한 뒤, 심전도로부터 심박동변이도의 선형특성(시간영역과 주파수영역)과 비선형특성을 분석하였다. 똑바로 누운 자세 또는 좌측으로 누운 자세에서 심박동변이도의 nHF가 더 작을수록, 이 자세들로부터 우측으로 누운 자세로 전환할 때 nHF가 더욱 증가하였다. 중증의 관상동맥질환 환자의 세 가지 누운 자세 중에서, 우측으로 누운 자세는 심장부교감신경계의 활성도를 가장 높게, 심장교감신경계의 활성도는 가장 낮게, 그리고 생체시스템의 복잡성은 가장 높게 유도함을 확인하였다.