Language：English   Publisher：Japan Society for Occupational Health  

Objective—To clarify the mechanisms of excessive risk of cardiovascular disease among taxi drivers, the effects of taxi driving with long work hours on taxi drivers’ blood pressure and heart rate variability were examined. Methods—We measured the physical activity level, ambulatory blood pressure, and Holter ECG in 34 healthy middle-aged male taxi drivers over one work day and the two following non-work days. The subjects worked for a 24-h period starting at 07:00, then rested from work for 48 h. Ambulatory blood pressure was recorded automatically at 30-min intervals over the 72-h period. Holter ECG records were also kept for the 72 h, and temporal changes in the R-R interval were analyzed by the complex demodulation method (CDM). The amplitude of the high frequency (HF) components (central frequency 0.30 Hz), and the ratio of low-frequency components (central frequency 0.09 Hz) to high-frequency components (L/H) was calculated. Results—Blood pressure during the work day was significantly higher than that during the non-work days, with a stronger effect in the hypertensive subjects. There were no significant overall differences in heart rate variability between the work day and the non-work days, but the temporal patterns of HF and L/H on the work day revealed a potent effect of reversed-phased circadian rhythm for work at night. Conclusions—Long duty taxi driving raises blood pressure and may increase cardiovascular risk as a result. The conflict between the circadian rhythms of autonomic nervous activity and work activity at night may also result in increased risk.

DOI： 10.1539/joh.44.214

CiNii Research

Language：Japanese   Publisher：Japan Society of Physiological Anthropology  

The purpose of this study was to determine the effects of water-based exercise training on vital age (VA) in older adults. Thirty-nine volunteers were randomly divided into an exercise group (WEX: 8 man and 13 women, age 69±4 yr), and control group (5 men and 11 women, age 68±4yr). The WEX participated in a 12-week supervised exercise program, 70 min/d, and 3 d/wk. Significant lowering in VA was noted in WEX (68.7±8.5yr→61.2±8.3yr), and no significant change was observed in control group (69.2±5.9→69.7±8.3yr). The results indicate that the WEX is an effective measure to lower the VA, thus improving the overall physical fitness in the elderly.

DOI： 10.20718/jjpa.7.2_87

CiNii Research

Language：English  

DOI： 10.1163/156855701321138914

PubMed

Language：Japanese   Publisher：日本体力医学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：一般社団法人 日本糖尿病学会  

症例は神経性食欲不振症の16歳女性で経管栄養後に低血糖発作を認め精査となる. 空腹時の血糖, IRIは正常. エレンタール<SUP>®</SUP>注入 (750kcal/5h) 開始3時間後のIRIは1400μU/mlと著増し, 終了1時間後に低血糖 (31mg/dl) となった. 低曲糖時のGH, コルチゾール, グルカゴンなどインスリン拮抗ホルモンの分泌障害とプロインスリン/IRI比の上昇を認めた. 成分栄養から半消化態栄養経管投与への変更により本症例の低血糖は消失した, 本症例においては, エレンタール<SUP>®</SUP>の十二指腸への急速投与により, アルギニンなどが過剰にインスリン分泌を刺激し, かつ視床下部・下垂体系の機能障害なども有するため, 糖供給の中断により重篤な低血糖を起こしたと推測された. 神経性食欲不振症患者に対する成分栄養の経管投与に際しては, 低血糖の発症に十分な注意が必要であると考えられた.

DOI： 10.11213/tonyobyo1958.43.373

CiNii Research

Language：Japanese   Publisher：日本体力医学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：一般社団法人 日本心身医学会  

DOI： 10.15064/jjpm.39.supplementii_36_2

CiNii Research

Language：Japanese  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Language：Japanese  

CiNii Research

Language：Japanese   Publisher：Japanese Society for Medical and Biological Engineering  

The mental and physical workload (MPWL) due to motorcycle (MC) and automobile (AM) operation were compared quantitatively by means of ECG R-R intervals (RRI). The RRI of 30 MC riders and 20 AM drivers were measured. Eight statistics were derived from RRI; average (RRM), mean coefficient of variance (mean CV_R-R), auto regressive variability (ARV), power of high-frequency region (HF), central frequency of high-frequency region (HFF), power of low-frequency region (LF), central frequency of low-frequency region (LFF) and ratio of LF and HF (LF/HF). As a result of factor analysis, three common factors which reflect, “stress level” (represented by mean CV_R-R & LF), “parasympathetic tone” (RRM & HF) and “randomness of RRI variability” (ARV) were extracted from these eight statistics. MC riders' stress level gradually increased in accordance with riding distance up to 260-320km, then it started to decrease and parasympathetic tone was enhanced in turn. This phenomenon can be comprehended so as to indicate the difficulty in maintaining attention. On the contrary, AM drivers' stress level increased steadily in accordance with driving distance, but no phenomena thought to affect the maintenance of attention was observed.

DOI： 10.11239/jsmbe1963.36.87

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：Japanese Heart Rhythm Society  

DOI： 10.5105/jse.18.203

CiNii Research

Language：Japanese  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Language：Japanese  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Language：Japanese   Publisher：Japanese Society for Medical and Biological Engineering  

A method to evaluate rider's mental and physical workloads (MPWL) using R-R interval (RRI) was studied and proposed. The RRI of 4 subjects riding a motorcycle over 400km was measured and compared with that of the non-riding day, and the relation with MPWL based on subjective evaluation was discussed. While the average RRI of 5 minutes duration, defined as RRM, is a statistic which would reflect MPWL, the effect of circadian rhythm is not negligible, and therefore RRM in long-term riding should be adjusted by the RRM in the non-riding day so as to reflect the rider's MPWL more clearly. The standard deviation of RRI reflects not only short-term RRI variability but also trend of RRI caused by transient change in tension. Thus, it is not suitable for describing tonic states such as rider's MPWL which is reflected by short-term RRI variability. To obtain a more robust statistic in relation to this variability, a new statistic named RRV15 was introduced. RRV15 is a statistic which would reflect tonic states, but the tonic states itself could show circadian rhythm, and so it is not possible to estimate pure MPWL directly from RRV15 itself. There was a remarkable tendency during the riding test for RRV15 to gradually decrease while riding and to recover quickly while taking a rest. Accordingly, a new statistic, RER, referred to as the Recovery Ratio, was defined to quantify recovery performance from the MPWL due to riding. This was an attempt to estimate the MPWL level from recovery performance in RRV15, and was confirmed to agree quite well with the subjective evaluation of MPWL in riding. This method does not require compensation with the non-riding day, and is believed to be practical and useful in evaluation the actual MPWL level in practical circumstances such as operating a vehicle.

DOI： 10.11239/jsmbe1963.34.291

CiNii Research

Language：Japanese   Publisher：Japanese Society for Medical and Biological Engineering  

In this study, the parameters obtained from the impulse response function in the time domain are proposed as new pamameters for evaluation of HRV (heart rate variability). The impulse response function is estimated from the autoregressive model by which the R-R interval time series is expressed. HRV during graded head-up tilt was analyzed using the parameters, ARV, TP, heart rate, CV_R-R, and a power spectrum density function. RHI, power, time constant, and settling time were obtained from the impulse response function. The RHI is the summation of the impulse response function during the transient decreasing of the function. The power is the average value of the square of the impulse response function of the maximum settling time. The time constant is the time to reach the output value of the system when stimulation is input to 1/<i>e</i> or less. The settling time is the time for the value of the impulse response function to become ±0.1 or less. ARV expresses the irregularity of the time series. TP evaluates the adjustment function of the system. The subjects were the healthy males aged 19 to 27 years old. The tilt angle was 0, 20, 30, 45, 60, 90, and 0 degrees, and it was changed, respectively, every four minutes. As a result, RHI, power and TP showed a high correlation between LF/HF, that is, the index of sympathetic nerve activity. ARV exhibited a high correlation between HF, that is, the index of the parasympathetic nerve. It was possible to analyze the autonomous nerve response by TP, ARV, RHI and the power of the impulse response function. With these parameters, the realization of a simple, portable autonomous nerve response analysis device targeting real-time, non-stationary data is expected.

DOI： 10.11239/jsmbe1963.34.161

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research

Language：English   Publisher：Japanese Circulation Society  

CiNii Research

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publisher：社団法人日本循環器学会  

CiNii Research