Journal of Physiological Anthropology最新文献

Aim: The phase angle (PhA), assessed using bioelectrical impedance analysis (BIA), is becoming increasingly popular as an index of muscle quality associated with various health-related outcomes. This study aimed to clarify the relationship between PhA and sedentary behavior (SB), light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA), which were objectively measured using accelerometers in older adults with disabilities requiring care.

Methods: We recruited 90 older adults (39 men and 51 women, mean age of 78.7 ± 6.7 years) with disabilities under the long-term care insurance system. Skeletal muscle mass index (SMI) and PhA of the lower limbs were measured using a multifrequency BIA instrument. Daily durations of SB, LPA, and MVPA per day were measured using a triaxial accelerometer. Nutritional status was assessed using the long form of the Mini Nutritional Assessment (MNA).

Results: The MVPA duration was significantly associated with lower limb PhA after adjusting for age, sex, SB and LPA durations, MNA score, and medical history (p = 0.037), whereas SB and LPA durations were not associated with lower limb PhA. The duration of SB, LPA, and MVPA were not significantly associated with lower limb SMI, whereas the MNA score was.

Conclusions: Lower limb PhA, but not lower limb SMI, was associated with MVPA duration, independent of nutritional status and medical history. Enhancing the duration of MVPA is needed to maintain the PhA and prevent further decline in physical function in older adults who require long-term care due to disabilities.

Since psychological and physiological responses to repeated exposure to mild heat has not been fully studied, the present study was designed to confirm overshooting responses in thermal sensation after repeated exposure to mild heat (i.e., the cooling period), the manner of change in the thermal sensation responses (TSRs) and the thermal comfort responses (TCRs) during the cooling period, and effect of short-term heat acclimation during repeated exposure to mild heat. In the summer, eight young adult male subjects (a mean age of 21.1 ± 1.4 years; a mean height of 173.1 ± 5.6 cm and a mean weight of 58.8 ± 7.5 kg) with clothing insulation (I_cl, clo) of 0.3 clo first stayed in the control room at 26 °C for 15 min, then moved to the main testing room at 33 °C for 10 min (condition 1), 15 min (condition 2), or 20 min (condition 3), and finally returned to the control room for 15 min. The exposure was repeated five times. TSR and TCR were recorded in a 5-min interval from the beginning of the first exposure. The tympanic temperature (T_ty), skin temperatures at the chest, forearm, front of the thigh, and front of the shin, and ECG and heart rate were continuously monitored. Local sweat rates at the same sites of skin temperature were monitored at the end of each exposure. Changes in T_ty and mean skin temperature (_T_sk) indicated no significant difference between conditions and no indication of short-term heat acclimation. Since the subjects voted nearly "cold" when _T_sk remained high at the beginning of the cooling period, overshooting responses in thermal sensation were repeatedly observed in all conditions. The subjects voted "slightly cool" at the end of cooling period while _T_sk kept decreasing during the cooling period. The thermally neutral _T_sk was then estimated to be 0.3 °C-4.2 °C lower than _T_sk observed prior to the first exposure. Thus, a residual effect on TSR during the cooling period was confirmed. Changes in the mean sweat rate, TSR and TCR showed significant differences between conditions but no indication of short-term heat acclimation. However, change in heart rate and ECG analysis implied the effect of short-term heat acclimation.

Background: Mental arithmetic tasks effectively induce psychological stress responses, but anticipatory stress responses before task onset are often overlooked. This study investigates how task difficulty influences anticipatory stress through heart rate variability time-domain analysis.

Methods: This study developed a standardized mental arithmetic task program using Unity, incorporating low, medium, and high levels by adjusting the amount of calculation and time limits. The participants were 12 healthy graduate and doctoral students. During the experiment, heart rate variability time indicators and the average RR interval were used as key physiological indicators to quantify psychological stress response. After the experiment, the participants were asked to complete the NASA Task Load Index (NASA-TLX) questionnaire to assess their workload.

Results: The NASA-TLX scores revealed significant differences in perceived workload among the three levels of task difficulty. The results indicated that task difficulty had a significant impact on anticipatory psychological stress response. High-level tasks elicited significantly greater anticipatory psychological stress responses compared to low-level tasks. Among the indicators used, the standard deviation of normal-to-normal (SDNN) intervals demonstrated particularly strong performance and may serve as a reliable and sensitive measure of anticipatory psychological stress response.

Conclusions: This study provides preliminary evidence supporting the use of SDNN as a complementary physiological indicator of anticipatory psychological stress responses. The findings suggest that task difficulty not only modulates individuals' anticipatory psychological responses on a cognitive level but also significantly shapes the dynamic trajectory of the SDNN during stress development. The observed sensitization effect indicates that higher-difficulty tasks can lead to enhanced anticipatory psychological stress responses in subsequent tasks. These results have potential implications for optimizing psychological stress response intervention strategies and for the development of standardized and replicable paradigms for anticipatory psychological stress research. Future studies should incorporate a larger and more diverse sample to further investigate how individual differences influence anticipatory psychological stress responses.

Background: Identifying and managing obesity in children is essential to prevent obesity-related diseases in adulthood. This study aimed to evaluate the association between body mass index (BMI), degree of obesity, waist circumference, waist-to-height ratio, and body fat-particularly excess body fat.

Methods: Participants included 660 children aged 9-12 years (349 boys and 311 girls). Fat mass, fat-free mass, and body fat percentage were assessed using bioelectrical impedance analysis. The discriminatory ability of BMI, degree of obesity, waist circumference, and waist-to-height ratio to identify excess body fat-defined as body fat percentage exceeding the 85th, 90th, or 95th percentile-was evaluated using receiver operating characteristic (ROC) curve and precision-recall (PR) curve analyses. Classification performance was further evaluated using a confusion matrix, accuracy, precision, recall, F1 score, Cohen's kappa coefficient, and Matthews correlation coefficient (MCC).

Results: The areas under the ROC curve (AUCs) and 95% confidence intervals (CIs) for BMI, degree of obesity, waist circumference, and waist-to-height ratio in identifying obesity based on body fat percentage were > 0.9 in both sexes in most cases. PR AUCs and 95% CIs for BMI and degree of obesity were ≥ 0.8 in most cases. Precision, recall, and F1 scores for BMI and degree of obesity in identifying obesity at the 85th or 95th percentiles were > 70% in nearly all cases. Kappa coefficients indicated substantial agreement between BMI and the 85th or 90th percentiles of body fat percentage, and moderate agreement for the degree of obesity. The MCC index showed a pattern similar to that of the kappa coefficients.

Conclusions: These findings suggest that BMI and degree of obesity are strongly associated with body fat percentage across the 85th, 90th, and 95th percentiles and that obesity classifications based on BMI as well as degree of obesity align closely with those based on body fat percentage.

Study objectives: Nonrestorative sleep (NRS) has been identified as a potential risk factor for physical and mental well-being in adults, but limited research exists for children and adolescents. This study aimed to clarify the factors associated with NRS in Japanese junior high school students.

Methods: The participants were 529 Japanese junior high school students in grades 7 through 9. Participants were asked to respond to Google Forms, and responses were obtained from 392 students. Sleep habits, history of coronavirus disease (COVID-19), physical symptoms, social isolation, and the presence of the symptoms of restless legs syndrome (RLS) were identified. NRS, insomnia symptoms, and depressive symptoms were evaluated using the Restorative Sleep Questionnaire (RSQ), Athens Insomnia Scale (AIS), and Patient Health Questionnaire (PHQ)-9, respectively. The cut-off value for NRS determination by the RSQ score was the mean of the scores that maximized the sensitivity and specificity sum for detecting participants with AIS and PHQ-9 scores of ≥ 6 and ≥ 5, respectively. NRS-associated sleep parameters and those associated with depressive symptoms were evaluated using binominal logistic regression analysis. Multinomial logistic regression (MLR) analysis was used to confirm the reproducibility of the binomial logistic regression analysis results with lower RSQ scores.

Results: The NRS group comprised 40.1% of participants and exhibited a higher prevalence of physical and depressive symptoms compared to those with restorative sleep. Logistic regression analysis, adjusted for sex, grade, and COVID-19 history, revealed the following odds ratios (95% confidence interval) for NRS: average total sleep time < 7 h 2.44 (1.16-4.33), AIS ≥ 6 2.74 (1.51-4.95), evening chronotype 2.58 (1.49-4.47), and RLS symptoms 2.21 (1.21-4.03). The same results were obtained using MLR as those obtained via binomial logistic regression analysis. Logistic regression analysis for depressive symptoms revealed that NRS displayed the highest odds ratio (95% CI) of 3.16 (1.90-5.27) among the sleep-related variables.

Conclusions: These findings suggest that NRS in Japanese junior high school students is associated with physical and mental health issues. Intervention and longitudinal studies are warranted to address NRS-associated sleep-wake problems in this age group.

Background: Omentin-1 (also known as intelectin-1) is a novel adipokine associated with metabolic diseases. However, its physiological role in body composition remains incompletely understood. Therefore, this study aimed to investigate the association between the circulating omentin-1 levels and whole-body and regional body composition parameters measured using dual-energy X-ray absorptiometry (DXA).

Methods: A population-based cross-sectional survey was conducted among school-aged children in Hamamatsu, Japan. Serum adipokine levels were measured using enzyme-linked immunosorbent assay, and associations between omentin-1 levels and DXA-based parameters were evaluated by multiple regression analysis after adjusting for potential confounding factors.

Results: The final study included 392 participants (192 boys, 200 girls, 75.2% of the source population; mean age 11.2 ± 0.3 years). Serum omentin-1 levels showed a significantly inverse association with nearly all DXA-based fat mass parameters. Inverse correlations were observed with fat-free soft tissue mass and serum leptin levels, whereas positive correlations were noted with adiponectin levels. The mean values for various body fat parameters, fat-free soft tissue mass, body mass index, and waist circumference were significantly decreased across tertiles of serum omentin-1 levels from lowest to the highest after adjusting for potential confounders.

Conclusion: Our results demonstrate that Japanese school-aged children with higher fat mass tended to have lower serum omentin-1 levels. These findings provide crucial insights into the link between omentin-1 levels and body composition, which may contribute to early health interventions for metabolic improvement.

Background: The thermos-physiological characteristics of medical personnel wearing protective clothing during prolonged activities under low oxygen pressure (LOP) and normal oxygen pressure (NOP) are crucial.

Methods: The average age of the 24 participants was 22.13 ± 1.849 years, with an average height of 168.58 ± 6.268 cm, an average weight of 61.62 ± 8.128 kg, and an average BMI of 21.59 ± 1.761 kg/m². Participants were first exposed to an LOP environment. The 6-h experiment involved a three-phase cycle (sitting, walking, and cardiopulmonary resuscitation (CPR)) repeated every hour. After a 2-week washout period, 24 participants were exposed to a NOP environment and repeated the aforementioned experimental procedure. Logistic regression and Cox analysis were used to assess the relationship between different oxygen pressures and human indicators. Restricted cubic spline (RCS) analysis was employed to examine the temporal changes in physiological indicators, and the Kaplan-Meier (K-M) method was used to plot survival curves.

Results: Each observation time point identified 120 min as the optimal protection time, with the greatest intergroup differences observed for both continuous (5/8 variables) and categorical (8/12 variables) parameters at this time point. Stepwise Regression analyses combining logistic and Cox regression identified six significant variables (P < 0.05): temperature, SpO₂, pulse pressure, thermal sensation vote (TSV), sultriness, and rating of perceived exertion (RPE). K-M analysis revealed significantly higher probabilities of adverse outcomes in the LOP group compared to the NOP group: SpO₂ abnormalities (HR = 1.439, 95% CI: 1.026-2.017; log-rank P = 0.022), High TSV scores (HR = 2.463 [1.537-3.946]; P < 0.001), High sultriness scores (HR = 1.603 [1.260-2.040]; P < 0.001). RCS analysis of LOP group data showed significant temporal effects: RPE exhibited a nonlinear upward trend (overall P < 0.001; nonlinear P = 0.002), reaching an inflection point at 200 min. SpO₂ demonstrated linear decline (P = 0.002/0.143; inflection point = 200 min). Pulse pressure showed covariate-dependent effects: nonsignificant before adjustment (P = 0.430) but significant after adjustment (P = 0.008/0.891; inflection point = 200 min).

Conclusions: Our research shows that 120 ~ 200 min is an optimal working time that does not affect the work efficiency of medical personnel.

Cold constitution refers to a phenomenon in which individuals have a higher sensitivity to cold and feel colder than others. This research aimed to examine the associations of morphological characteristics, personal factors, thermal perceptions, and local skin temperature (t_sk) with cold constitution by conducting a field experiment. It also explored differences in these aspects between individuals with and without cold constitution, in a thermoneutral office environment during summer and winter, and in 89 and 75 sedentary workers, respectively. A questionnaire survey was conducted to classify the cold constitution (CC) and non-cold constitution (NC) groups. The results indicated that females and individuals with lower body mass index (BMI) were more likely to have cold constitution. The CC group exhibited a significantly lower metabolic rate (M) in both seasons, lower thermal sensation votes, warmer thermal preference, and a greater predicted percentage of dissatisfied in summer (p < 0.01). No significant differences were observed in clothing insulation between the groups; however, winter clothing was significantly higher compared to summer for both groups (p < 0.01). Furthermore, the CC group exhibited significantly lower local skin temperatures at distal body parts (p < 0.01). Significant correlations were observed for gender, BMI, M, thermal sensations, and distal t_sk with cold constitution. Adjusting the effects of gender and BMI, most correlations with cold constitution weakened. However, thermal sensation remained significant in summer, while no correlation was observed with t_sk. These findings emphasize the significant associations of morphological characteristics, personal factors, and thermal perceptions with cold constitution and show the importance of assessing the thermal environment.

Background: Nutrition is a modifiable factor in skin ageing, but its effects remain inconsistently quantified. This meta-analysis assessed human studies from the Web of Science on dietary intake and skin ageing, using pooled standardised mean differences (pSMD). Interventions included carotenoids, collagen, lipids and fatty acids, polyphenols, prebiotics and probiotics, and vitamins. We included full-text English articles and excluded non-human, disease-focused, topical or in vitro studies. Publication bias was assessed using Egger's test and funnel plots. Results are shown as forest plots.

Main body: Sixty-one studies were meta-analysed. Collagen reduces wrinkles (pSMD = - 0.94 [- 1.39, - 0.49], p = 4.82 × 10^-5). Lipids and fatty acids (pSMD = - 0.62 [- 0.92, - 0.31], p = 7.89 × 10^-5) and polyphenols (pSMD = - 0.48 [- 0.74, - 0.21], p = 3.96 × 10^-4) also reduce wrinkles without significant publication bias. Several interventions improve skin hydration, including collagen (pSMD = 0.66 [0.29, 1.04], p = 5.99 × 10^-4), lipids and fatty acids (pSMD = 0.54 [0.28, 0.80], p = 4.36 × 10^-5), polyphenols (pSMD = 0.59 [0.37, 0.80], p = 6.43 × 10^-8), and prebiotics and probiotics (pSMD = 0.71 [0.25, 1.16], p = 2.64 × 10^-3). Specific interventions target distinct ageing phenotypes. Carotenoids most effectively reduce redness (pSMD = - 0.53 [- 1.02, - 0.04], p = 3.39 × 10^-2), and collagen reduces pigment spots (pSMD = - 0.16 [- 0.31, - 0.003], p = 4.56 × 10^-2). Lipids and fatty acids improve elasticity (pSMD = 0.49 [0.14, 0.83], p = 5.45 × 10^-3), while polyphenols strengthen barrier integrity (trans-epidermal water loss pSMD = - 0.50 [- 0.79, - 0.22], p = 6.39 × 10^-4).

Conclusion: Dietary components target specific skin ageing phenotypes. Carotenoids, collagen, lipids and fatty acids, and polyphenols are particularly effective for redness, pigment spots, elasticity, and barrier integrity, respectively. Lipids, fatty acids, and polyphenols show broad benefits across multiple phenotypes. Shared mechanisms may contribute to overlapping effects. Evidence gaps remain, especially regarding carotenoids and vitamins. Future studies could explore combinatorial dietary interventions. This research is primarily supported by a Singapore National Medical Research Council grant.

The recent Journal of Physiological Anthropology article on polycythemia among Tibetan highlanders (Arima et al., J Physiol Anthropol 43:25, 2024) piqued our interest because we collected similar data in the same Nepali village in Upper Mustang two years later with notably different results (Cho et al., Evol Med Public Health 2017:82-96, 2017; Ye et al., Proc Natl Acad Sci U S A 121:e2403309121, 2024). Arima et al report high prevalences of chronic disease and conclude that Tsarang villagers have poor health. Here, we describe our relevant findings to show that authors' definitions and other research design elements can yield different population health implications. Our study sampled ethnic Tibetan Upper Mustang women 39 Years and older in 2012 who had been married or pregnant and were lifelong residents of this village at 3500m. At our 2019 follow-up study, the women were 46 Years and older. Fifty-five of the 64 eligible Tsarang residents (85%) participated in 2019 study designed to examine the influences of genes and physiology on reproductive success. Arima et al. sampled all Tsarang residents 18 or older in 2017, therefore, our studies include many of the same women in their mid-40s and older. Arima et al reported that 12% of the sample were polycythemic, whereas we found none; they reported 26% obesity whereas we found none; they showed 17% of the sample had hypertension, whereas we found 27%. Factors that may account for the differences in estimates of chronic disease prevalence in Tsarang include age differences in the samples, a wider age range in the currently reported sample, undefined cut-off values for disease categories, while we applied and reported chronic diseases using standard definitions. Because our study did not replicate the findings of Arima et al., we caution against concluding that women in Tsarang have alarming rates of obesity, polycythemia, and hypoxia. Our studies agree that high blood pressure is a public health problem among women in Tsarang. Future use of clear definitions of disease categories will help establish a common understanding of a population's health.