• Journal of Acupuncture Research
• /
• v.20 no.4
• /
• pp.157-169
• /
• 2003

Objective : The effects of electroacupuncture(EA) stimulation on heart rate variability(HRV) for healthy adults are investigated with power spectrum analysis(PSA) of HRV. Methods : The HRVs of every 10 minute for 22 healthy volunteers(13 men and 9 women) were measured for an hour with SA-3000P(Medicore Co., Ltd., Korea). The median age with arithmetic range of 13 men and 9 women was 26.00 years with 22.75~27.00 years. The initial 20 minutes were defined as baseline period(pre-EA period), the following 20 minutes as the EA period and the last 20 minutes as the post-EA period. In each EA periods, volunteers received EA(2Hz, 0.6~0.8ms duration, maximal tolerated stimulation without discomfort) on the right Zusanli(ST36), Shangjuxu(ST37) acupoints while supine, resting. Results : Heart rate of volunteers at post-EA period was significantly decreased compare to that of pre-EA period, while SDNN at post-EA period was significantly increased. Heart rate at EA period was significantly decreased compare to that of pre-EA period, but Ln(LF) and LF/HF at EA period were significantly increased. Ln(HF) at post-EA period was significantly decreased compare to that of EA period, while the other variables were not significantly changed. Conclusions : The results suggest that EA in healthy adults is associated with changed activity in the sympathetic and parasympathetic nervous system. Further study is needed for investigating the effects of EA on HRV and autonomic nervous system.

• The Korean Journal of Physiology
• /
• v.30 no.1
• /
• pp.43-51
• /
• 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.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.18 no.2
• /
• pp.78-82
• /
• 2014

Purpose The physiological and biochemical responses of healthy men and women to life stress were measured in order to investigate the correlation between these two responses under the normal situation. Materials and Methods The population of the research is some randomly chosen health college students located in Daejeon City during the period from August to September 2014, and the sample of 94 students. Heart rate variability (HRV), blood pressure (BP) were selected as physiological stress indices and serum cortisol level was used as a biochemical stress biomaker. The data which is collected used SPSS19.0 programs and frequency and percentage and T-test, correlation. Results Male showed the significant higher value of serum cortisol level (p<0.05), BP (p<0.05), and LF/HF ratio of HRV (p<0.05) than female. The difference of BP between correlated significantly with serum cortisol level (p<0.05). The LF/HF ratio of HRV also correlated significantly with serum cortisol level (p<0.05) Conclusion We suggest that LF/HF ratio of HRV and BP may be good indices for the assessment of life stress.

• The Journal of Internal Korean Medicine
• /
• v.30 no.3
• /
• pp.510-524
• /
• 2009

Objective : This study was designed to find the correlation between Sasang Constitution and heart rate variability(HRV). Method : There were 665 subjects (280 men and 385 women), between 39 and 72 years old. in a rural community. Sasang Constitution was diagnosed by a Sasang constitutional specialist using PSSC (Phonetic System for Sasang Constitution), face and tongue photo and checkup-list. A structured-questionnaire was used to assess the general characteristics. HRV was recorded using SA-2000 (medi-core). HRV was assessed by time domain and by frequency domain analysis. Metabolic syndrome was defined on the basis of clustering of risk factors, when three or more of the following cardiovascular risk factors were included : blood pressure, fasting blood sugar, triglyceride HDL-cholesterol, and abdominal obesity (waist). Because of the skewness of the data, logarithmic transformation was performed on the absolute units of the spectral components of HRV, and the resulting logarithmic values and normalized units were compared between the groups by a logistic regression. The 95% confidence interval (CI) of the odds ratio was used and calculated from the data laid out for a cross sectional study. Results : 1. Odds ratios of Taeeumin and Soeumin in female adults below 60 years old were significantly lower than that of Soyangin in LF norm and LF/HF ratio. Odds ratios of Taeeumin and Soeumin in female adults below 60 years old were significantly higher than that of Soyangin in HF norm. 2. There was no significant correlation between HRV and Sasang Constitution in female adults from 60 years old and over. 3. There was no significant correlation between HRV and Sasang Constitution in male adults. Conclusion : There is a statistically significant correlation between the HRV and Sasang Constitution. There is a tendency of increase in the sympathetic activity in Soyangin. There is a tendency of decrease in the parasympathetic activity in Taeeumin and Soeumin.

• The Journal of Internal Korean Medicine
• /
• v.33 no.3
• /
• pp.284-297
• /
• 2012

Objectives : This study was performed to investigate characteristic indice of heart rate variability (HRV) according to presence of metabolic syndrome (MS), pattern identification. Methods : We analyzed 167 subjects who participated in a stroke check-up. We classified the subjects into two groups as MS (n=48) and non-MS (n=119) based on NCEP ATP III. First, we investigated pattern identification of all subjects based on Korean Standard Pattern Identifications for Stroke-III. Second, we surveyed significance of HRV indices between MS and non-MS groups. Third, we investigated significance of HRV indices between classified DP of MS and classified DP of non-MS. Fourth, we investigated significance of HRV indices between classified DP of MS and non-MS. Fifth, we investigated significance between components of MS and HRV indices. Results : 1. SDNN, RMS-SD, HF, Ln(HF), and HF (NORM) were significantly lower in the MS than non-MS group. LN (TP), LF/HF were significantly higher in the MS than non-MS. 2. Ln (HF), Ln (TP), and LF/HF were statistically significant in the classified DP of MS group. 3. RMS-SD, and Ln (HF) were significantly lower in the abdominal obesity group than in the non-abdominal obesity group. SDNN, RMS-SD, TP, Ln (TP), VLF, Ln (VLF), and Ln (LF) were significantly lower in the hypertension group than in the non-hypertension group. RMS-SD was significantly lower in the diabetes group than in the non-diabetes group. Mean HRT,LF/HF were significantly higher in the hypertriglyceridemia than non-hypertriglyceridemia group, but Ln (HF), RMS-SD, and HF (NORM) were significantly lower in the hypertriglyceridemia than non-hypertriglyceridemia group. Conclusions : We found a few significant relationships between classified DP of MS and HRV indices. The resluts demonstrate that MS has potentially negative effects on the cardiovascular system, and these effects could be detected by HRV.

• The Journal of Internal Korean Medicine
• /
• v.27 no.4
• /
• pp.822-826
• /
• 2006

Objectives : Essential hyperhidrosis is a socially and occupationally disabling disorder. There are many suggestions that hyperhidrosis is associated with the autonomic nervous system, especiallythe sympathetic system. This study was designed to investigate the autonomic nerve system in patients with essential hyperhidrosis and healthy controls by the frequency domain analysis of heart rate variability (HRV). Methods : 17 head-hyperhidrosis patients in the ambulatory care were investigated. All were inspected at the first medical examination. using the PSA of HRV. HRV was measured for minutes after 5 minutes bed rest. We checked the frequency domain analysis of HRV (i.e. TP, VLF, LF, HF) which were transformed into natural logarithm of patients against the standard measures of the HRV components. Then we compared the values of patients with means of normal Korean subjects. Results : The values of natural logarithmic measure of HRV (LnTP, LnHF, LnLF, LnVLF) of patients With head-hyperhidrosis we examined were $6.85{\pm}1.61$, $4.93{\pm}$2.00, $5.40{\pm}1.83$, and $6.13{\pm}1.37$, respectively. None of these values were higher than means of normal subjects. Conclusions : This study suggests that the function of the autonomic nervous system does not increase in patients with head-hyperhidrosis.

• Journal of Biomedical Engineering Research
• /
• v.25 no.6
• /
• pp.581-587
• /
• 2004

Conventional power spectrum methods based on FFT, AR method are not appropriate for analyzing biomedical signals whose spectral characteristics change rapidly. On the other hand, time-frequency analysis has more desirable characteristics of a time-varying spectrum. In this study, we investigated the spectral components of heart rate variability(HRV) in time-frequency domain using time frequency analysis methods. In the various time-frequency kernels functions, we studied the suitable kernels for the analysis of HRV using synthetic HRV signals. First, we evaluated the time/frequency resolution and cross term reduction of various kernel functions. Then, from the instantaneous frequency, obtained from time-frequency distribution, the method extracting frequency components of HRV was proposed. Subjects were 17 healthy young men. A coin-stacking task was used to induce mental stress. For each subjects, the experiment time was 3 minutes. Electrocardiogram, measured during the experiment, was analyzed after converted to HRV signal. In the results, emotional stress of subjects produced an increase in sympathetic activity. Sympathetic activation was responsible for the significant increase in the LF/HF ratio. Subjects were divided into two groups with task ability. Subjects who have higher mental stress have lack of task ability.

• Journal of the Korean Applied Science and Technology
• /
• v.36 no.1
• /
• pp.142-152
• /
• 2019

This study aimed to explore the association between obesity index and heart rate variability (HRV) in college-aged male smokers. A total of 85 male college students (> 10 cigarettes per day for at least 3 years) were participated in this study. According to a standardized protocol, body mass index (BMI), percent body fat (%BF), waist circumference (WC), and waist-to-hip ratio (WHR) were taken as obesity indices. Resting r-r interval was monitored for HRV analysis as an indicator of cardiac autonomic regulation. Compared with low WHR subjects, high WHR subjects had significantly lower values of rMSSD, pNN50, HF, and SD1, suggesting decreased parasympathetic activity. No such differences in LF/HF ratio were found between the WHR-based subgroups. Bivariate correlation analysis showed that obesity indices of WC, WHR, and %BF were significantly associated with rMSSD, pNN50, HF, and SD1, with a tendency for correlation coefficient to be higher with WHR than with WC or %BF. No significant association was found between BMI and HRV parameters indicative of parasympathetic activity. This study suggest that central obesity is significantly associated with decrease in parasympathetic activation, independent of BMI as an indicator of obesity, in male college smokers.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.57 no.6
• /
• pp.1087-1094
• /
• 2008

This study describes a system for human sensibility evaluation using PPG(photoplethysmogram) signal and biofeedback algorithm to respond the bad(negative) mood. For this objective, PPG signals for two emotional states(positive/negative) are collected. To evoke the test emotions, happy(or joyful) and sad(or irritating) movie files are collected and played in subjects' monitor. From the acquired PPG signal, the heart rate variability(HRV) is calculated. Using the HRV and its FFT spectra, the human sensibility is evaluated. Since the heart is a representative organ which is controlled by the autonomic nervous system(ANS), the ANS may reflect the changes in emotion. The biofeedback algorithm is designed with motion image player interacting with the results of the sensibility evaluation. It was shown that HRV was changed according to the subject's emotions. Accordingly, the sensibility evaluation test showed feasibility of the our method.

• Journal of Oriental Neuropsychiatry
• /
• v.18 no.3
• /
• pp.309-319
• /
• 2007

Chest pain is classified into two major categories of cardiac chest pain and non-cardiac chest pain. Cardiac chest pain is caused by cardiovascular disease, for example, myocardial infarction, angina pectoris, valvular heart disease, cardiac enlargement or hypertrophy, dissecting aortic aneurysm, pericarditis, myocarditis, etc. When the chest pain is not attributed to heart disease, it is termed non-cardiac chest pain. Non-cardiac chest pain is caused by pulmonary, gastrointestinal, musculoskeletal disease, psychiatric factor, etc. In tills case, we treated a 54-year old female patient who was diagnosed with dilated cardiomyopathy and suspicious sick sinus syndrome. She complained of chest pain, exertional dyspnea, dizziness and headache. For treatment, we made use of Yugultangami(六鬱湯加味) and Daejobwan(大造丸). Before and after treatment, we measured Heart rate variability(HRV). In result, the clinical symptoms were improved and there was a significant increase in assessmeut by Heart rate variability(HRV). Tills result suggests that Yugultaugami aud Daejowhan have a good effect on cardiac chest pain.