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Many activity trackers have been developed, but steps can still be inconsistent from one monitor to another.What are the differences and associations between the steps of 13 selected consumer-based and research-grade wearable devices during 1 standardized day in a metabolic chamber and 15-day free-living trials?In total, 19 healthy adults between 21 and 50 years-old participated in this study. Participants were equipped with 12 accelerometer-based active trackers and one pedometer (Yamasa) in order to monitor the number of steps per day. The devices were worn on the waist (ActiGraph, Omron, Actimarker, Lifedorder, Withings, and Yamasa) or non-dominant wrist (Fitbit, Garmin, Misfit, EPSON, and Jawbone), or placed in a pocket (Omron CaloriScan, and TANITA). Participants performed structured activities over a 24 h period in a chamber (Standardized day), and steps were monitored in the same participants in free-living trials for 15 successive days using the same monitors (free-living days).When the 13 monitors were ranked by their steps, waist-worn ActiGraph was located at the center (7th) of the monitors both in the Standardized (12,252 ± 598 steps/day, mean ± SD) and free-living days (9295 ± 4027 steps/day). The correlation between the accelerometer-based devices was very high (r = 0.87-0.99). However, the steps of Yamasa was significantly lower in both trials than ActiGraph. The wrist-worn accelerometers had significantly higher steps than other devices both trials (P 0.05). The differences between ActiGraph and Actimarker or Lifecorder was less than 100 steps/day in the Standardized day, and the differences between ActiGraph and Active Style Pro was less than 100 steps/day in the free-living days. Regression equation was also performed for inter-device compatibility.Step obtained from the wrist-worn, waist-worn, and pocket-type activity trackers were significantly different from each other but still highly correlated in free-living conditions.

Background Meals, particularly carbohydrate intake, determine diurnal blood glucose (BG) excursions. However, the effect of meals with variable carbohydrate content on diurnal BG excursions remains poorly understood, despite routine consumption of meals that vary daily. Objective The aim of this study was to verify our hypothesis that glycemic response is elevated when a meal with a higher carbohydrate content follows a meal with a lower carbohydrate content. Design This was a secondary analysis of a study whose primary endpoint was energy metabolism (e.g., energy expenditure and substrate oxidation). This crossover study was designed to test BG responses to 3 types of meals with different macronutrient contents [regular meals (R), meals with a high-carbohydrate breakfast (CB), and meals with a high-fat breakfast (FB)] using a continuous glucose monitoring system. The R test included 3 meals/d with the same macronutrient composition; the CB test, a high-carbohydrate meal at breakfast, a high-fat meal at lunch, and a high-carbohydrate meal at dinner; and the FB test, a high-fat meal at breakfast, a high-carbohydrate meal at lunch, and a high-carbohydrate meal at dinner. Each test had similar daily macronutrient compositions, except CB and FB had larger variations in carbohydrate content than R. Fourteen healthy young men were tested in random order and underwent whole-body indirect calorimetry. Results Daily peak BG concentrations were higher for the CB (mean ± SD: 143.9 ± 25.3 mg/dL) and FB (140.2 ± 24.8 mg/dL) conditions than for the R condition (127.5 ± 15.7 mg/dL). Postprandial BG peaks after a high-carbohydrate meal were ∼20 mg/dL higher when a previous meal was relatively high-fat than when not high-fat (P < 0.05 for all). A multiple regression analysis indicated that the postprandial glycemic response was negatively associated with the preprandial respiratory quotient. Conclusions Our findings indicate that switching from high-fat to high-carbohydrate meals contributes to larger postprandial BG excursions, along with alterations in prioritization of carbohydrate utilization. This study was registered at the UMIN Clinical Trials Registry as UMIN000028895.

OBJECTIVES: In this study we investigated the effects of hydrogen (H(2)) supplement, in the form of calcium bound H(2) powder capsules, on aerobic and anaerobic cycling exercise. METHODS: Trained male subjects participated in a randomized, double-blind, crossover design trial and received H(2)-rich calcium powder (HCP) supplement (1500 mg/day, 2.544 μg/day of H(2) gas) or H(2)-depleted placebo (PLA) (1500 mg/day) for 3 consecutive days. Aerobic experiment: Eighteen subjects carried out a cycling incremental exercise starting at 20 watts (W) work rate, and increasing by 20 W/2 minutes until exhaustion. Blood gases including pH, bicarbonate ion (HCO(3)(−)), partial pressures of CO(2) (PCO(2)), metabolic profile including lactate (Lac), and electrolytes including chloride (Cl(−)) were measured at rest and at 120-, 200-, and 240-W work rates. Anaerobic experiment: Six subjects carried out a 30 second Wingate anaerobic exercise test (WAnT) bout with a resistive load of 7.5% of body mass. Lac was then measured at 1-, 3-, 5-, and 15-minutes following the WAnT exercise. RESULTS: Aerobic experiment: At rest, HCP had a significantly lower pH (P = 0.048), Cl(−) (P = 0.011), and a higher HCO(3)(−) (P = 0.041), PCO(2) (P = 0.026) compared to the PLA group. During exercise, pH decrease (supplement effect: P = 0.043) and the HCO(3)(−) increase (supplement effect: P = 0.030) continued in the HCP group. Additionally, HCP did not affect peak work load and exercise duration. And no changes were noted in Lac at rest or during exercise. Anaerobic experiment: HCP did not affect peak power output or Lac recovery following WAnT. However the average power output during exercise was significantly higher in the HCP group (P = 0.019) compared to the PLA group. CONCLUSIONS: HCP supplementation following 3 days of intake, slightly lowered pH during aerobic exercise, and increased average power output in the anaerobic WAnT exercise compared to the PLA group. HCP supplement might have an ergogenic effect in an anaerobic exercise setting. FUNDING SOURCES: This study was supported by The Japan Society for the Promotion of Science, and the Ministry of Education, Science, and Culture of Japan. In addition, we received a research grant from the company ENAGEGATE Inc. and they provided the HCP supplement and placebo. However, no intercession, restrictions or agreements of any kind was imposed between parties regarding research design, results or publications.

To evaluate the long-range cross-correlation in non-stationary bi-variate time-series, detrending-operation-based analysis methods such as the detrending moving-average cross-correlation analysis (DMCA), are widely used. However, its mathematical foundation has not been well established. In this paper, we propose a generalized theory to form the foundation of DMCA-type methods and introduce the higher-order DMCA in which Savitzky-Golay filters are employed as the detrending operator. Using this theory, we can understand the mathematical basis of DMCA-type methods. Our theory establishes a rigorous relationship between the DMCA-type analysis, the cross-correlation function analysis, and the cross-power spectral analysis. Based on the mathematical validity, we provide a practical guide for the use of higher-order DMCA. Additionally, we present illustrative results of a numerical and real-world analysis. To achieve reliable and accurate detection of the long-range cross-correlation, we emphasize the importance of time-lag estimation and time scale correction in DMCA, which has not been pointed out in the previous studies. Keywords: Long memory process, Complex system interaction, Cross-spectral analysis

The island of Ishigaki Jima, located in the western part of the southern Ryukyu Arc, Japan, is underlain by a basement comprising the Tumuru and Fu-saki formations. The former is a pelitic glaucophane schist with a metamorphic age of 220–190 Ma, and the latter is a weakly metamorphosed accretionary complex, composed mainly of chert, mudstone and sandstone with minor amounts of limestone and mafic rocks. The Fu-saki Formation was weakly metamorphosed at ∼140 Ma. Latest Carboniferous–Early Jurassic microfossils have been obtained from the limestones, cherts and siliceous mudstones of this formation, but no fossils have been collected from the phyllitic mudstones. The radiolarian fauna of the phyllitic mudstones described herein indicates a late Pliensbachian–early Toarcian (Early Jurassic) age. This result, when combined with existing data, enables the reconstruction of an oceanic plate stratigraphy, showing a succession of (in ascending order) Upper Carboniferous–Triassic cherts, Sinemurian–lower Pliensbachian siliceous mudstones and upper Pliensbachian–lower Toarcian phyllitic mudstones and sandstones. The radiolarians from the phyllitic mudstones are important in constraining the timing of the accretion of the Fu-saki Formation to the base of the Tumuru Formation.

Strenuous exercise may have the detrimental effects on visual perception. However, it is unclear whether visual resolution is related to the detrimental effects on visual perception. The purpose of this study was to examine whether the effects of strenuous exercise on visual perception are dependent on visual resolution. Given that visual resolution decreases in the periphery of the visual field, we hypothesized that if visual resolution plays a role in the detrimental effects on visual perception, the detrimental effects may be exaggerated toward the periphery of the visual field. Simple visual reaction time was measured at rest and during cycling at 40% and 75% peak oxygen uptakes (VO(2)). Visual stimuli were randomly presented at 2°, 10°, 30°, and 50° to either the right or left of the midpoint between the eyes with equal probability. RT was fractionated into premotor and motor components (i.e. premotor time and motor time) based on electromyographic recording. The premotor time during exercise at 40% peak VO(2) was not different from that at rest. In contrast, the premotor time during exercise at 75% peak VO(2) was significantly longer than that at rest (p=0.018). The increase in the premotor time was observed irrespective of eccentricity, and the detrimental effects were not exaggerated toward the periphery of the visual field. The motor time was not affected by exercise. The current findings suggest that the detrimental effects of strenuous exercise on visual perception are independent of visual resolution.