Using wet-bulb globe temperature meters to examine the effect of heat on various tennis court surfaces.

In this study, we evaluated the thermal environments of different tennis courts using wet-bulb globe temperature (WBGT) meters. WBGT meters were installed in an outdoor hard court, sand-filled artificial grass court, and clay court (a softball field), and measurements were taken hourly from 9:00 to 17:00 on weekdays from June 1 to September 21, 2022. The results were compared with data from different courts and the nearest Japan Meteorological Agency station (JMA WBGT) based on the Japan Sports Association's guidelines for exercise to prevent heat stroke. The median WBGT on each court was significantly higher for hard courts at the "Warning" (25 ≤ JMA WBGT < 28) level or above, sand-filled artificial grass courts at the "Severe Warning" (28 ≤ JMA WBGT < 31) level or above, and clay courts at the "Danger" (31 ≤ JMA WBGT) level than the JMA WBGT. Compared with the JMA WBGT, hard and sand-filled artificial grass courts are played on under particularly hot conditions. The results of this study could indicate to tournament organizers and coaches the importance of measuring the WBGT on each court surface from an early stage to prevent heat-related incidents.

Age-wise examination of the association of obesity based on body mass index and waist circumference with metabolic diseases in comprehensive health checkup participants.

Aim: Body mass index and waist circumference are used for obesity diagnosis and screening of visceral fat; however, their evidence in older adults is insufficient. This study investigated the age-specific association of body mass index and waist circumference with metabolic diseases, assessing their applicability as diagnostic criteria for individuals aged ≥65 years. Methods: Analysis included 46,324 individuals aged ≥18 years, categorized into five age groups: 18-44, 45-54, 55-64, 65-74, and ≥75 years. Logistic regression analyses identified associations between obesity and metabolic diseases, stratified by age and sex. Results: Men with obesity based on body mass index had a significantly high risk of hypertension, diabetes mellitus, and dyslipidemia across all age groups (all, p < 0.05). Obesity based on waist circumference was significantly positively associated with all metabolic diseases (all, p < 0.05). Women with obesity based on body mass index and waist circumference had a significantly high risk of all metabolic diseases across all age groups (all, p < 0.05), except for diabetes mellitus in individuals aged ≥75 years. Conclusions: Participants with obesity based on body mass index and waist circumference exhibited a high risk of hypertension, diabetes mellitus, and dyslipidemia among those aged 18-74 years and men aged ≥75 years. This study contributes to the early prevention and control of metabolic diseases.

A body shape index is useful for BMI-independently identifying Japanese patients with obesity at high risk of cardiovascular disease.

BACKGROUND AND AIM: Obesity with multiple metabolic syndrome (MetS) components and/or with skeletal muscle loss is at high risk of cardiovascular disease (CVD). This study aimed to clarify the utility of anthropometric indices for identifying patients with overweight/obese at high risk of CVD based on having multiple MetS components and skeletal muscle loss. METHODS & RESULTS: This cross-sectional study included 188 overweight/obese (BMI ≥25 kg/m2, Japanese patients; 73 men and 115 women, mean age 55.7 years). First, we performed correlation analysis among seven anthropometric indices, body mass index (BMI), percentage body fat, waist circumference (WC), waist-to-hip ratio (WHpR), waist-to-height ratio (WHtR), a body shape index (ABSI), and body roundness index (BRI). Unlike the others, only ABSI was not correlated with BMI. Then, we conducted receiver operating characteristic analysis to assess the predictive abilities of anthropometric indices for having multiple MetS components. WC, WHpR, WHtR, BRI, and ABSI had significant predictive abilities for having multiple MetS components. Furthermore, multiple regression analysis showed that only ABSI had significantly negative associations with all sarcopenia-evaluated indices (skeletal muscle mass index [SMI], handgrip strength [HGS], and muscle quality [MQ]), irrespective of sex and age. Finally, an analysis of covariance showed that the high ABSI group had significantly lower SMI and HGS than the low ABSI group, irrespective of sex and age. CONCLUSION: ABSI was deemed useful for BMI-independently identifying Japanese patients with overweight/obese at high risk of CVD based on having multiple MetS components and skeletal muscle loss. Clinical trials (the unique trial number and the name of the registry) ID: UMIN000042726.

A combined index of waist circumference and muscle quality is associated with cardiovascular disease risk factor accumulation in Japanese obese patients: a cross-sectional study.

PURPOSE: To identify obese patients at high risk of cardiovascular disease (CVD) using a combined index of obesity and sarcopenia. METHODS: In this cross-sectional study, we firstly conducted analysis of covariance to select each index most associated with the CVD risk score, the number of concomitant CVD risk factors, among obesity- (body mass index, percentage body fat, or waist circumference [WC]) and sarcopenia-evaluated indices (skeletal muscle mass index, handgrip strength, or muscle quality [MQ]), respectively in 188 Japanese obese patients (BMI ≥ 25 kg/m2, 73 men and 115 women). Next, we conducted multivariate logistic regression analysis to compare the four groups (Group A-D) classified by medians of the selected indices. RESULTS: WC and MQ were selected as the indices most associated with the CVD risk scores, respectively. The CVD risk score was significantly higher in Group B (low WC and low MQ) and Group D (high WC and low MQ) with higher prevalence of diabetes as compared with Group A (low WC and high MQ). Adjusted for sex and age, odds ratios for CVD risk scores = 2 were significantly higher in Group B, Group C (high WC and high MQ), and Group D compared with Group A. Furthermore, odds ratios for CVD risk scores = 3 were significantly higher only in Group D compared with Group A (4.29 [95% confidence interval: 1.49-12.33], p = 0.007). CONCLUSION: Combined index of WC and MQ was useful in Japanese obese patients at high risk of CVD, regardless sex and age.

Phase angle from bioelectrical impedance analysis is a useful indicator of muscle quality.

BACKGROUND: Methods that facilitate muscle quality measurement may improve the diagnosis of sarcopenia. Current research has focused on the phase angle (PhA) obtained through bioelectrical impedance analysis (BIA) as an indicator of cellular health, particularly cell membrane integrity and cell function. The current study therefore aimed to evaluate the relationship between the PhA and muscle quality and muscle-related parameters and to determine factors associated with the PhA. Moreover, we attempted to determine the cut-off value of PhA for predicting sarcopenia. METHODS: First-year university students (830 male students, 18.5 ± 0.6 years old; 422 female students, 18.3 ± 0.5 years old) and community-dwelling elderly individuals (70 male individuals, 74.4 ± 5.5 years old; 97 female individuals, 73.1 ± 6.4 years old) were included. PhA and other body composition data were measured using BIA, while muscle quality was calculated by dividing handgrip strength by upper limbs muscle mass. The relationship between PhA and the aforementioned parameters were then analysed, after which the cut-off value of PhA for predicting sarcopenia was examined. RESULTS: Multiple linear regression analysis revealed that age, skeletal muscle mass index (SMI), and muscle quality were independently associated with PhA in both sexes [male (age: standardized regression coefficient (ß) = -0.43, P < 0.001, SMI: ß = 0.61, P < 0.001, muscle quality: ß = 0.13, P < 0.001) and female (age: ß = -0.56, P < 0.001, SMI: ß = 0.52, P < 0.001, muscle quality: ß = 0.09, P = 0.007)]. Participants with sarcopenia had a significantly lower PhA compared with those without it (sarcopenia vs. non-sarcopenia: young male participants, 5.51 ± 0.41° vs. 6.25 ± 0.50°, P < 0.001; young female participants, 4.88 ± 0.16° vs. 5.37 ± 0.44°, P = 0.005; elderly female participants: 4.14 ± 0.29° vs. 4.63 ± 0.42°, P = 0.009). Although no significant findings were observed in elderly male participants, the same tendency was noted. Receiver operating characteristic (ROC) curve analysis indicated that PhA had good predictive ability for sarcopenia in young male, elderly male, young female, and elderly female participants (area under the ROC curve of 0.882, 0.838, 0.865, and 0.850, with cut-off PhA values of 5.95°, 5.04°, 5.02°, and 4.20° for predicting sarcopenia, respectively). CONCLUSIONS: The PhA reflected muscle quality and exhibited good accuracy in detecting sarcopenia, suggesting its utility as an index for easily measuring muscle quality, which could improve the diagnosis of sarcopenia.