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Background and Objectives: The aim of this study was to investigate the effects of 12-week somatosensory games on heart rate variability and sleep-related biomarkers in middle-aged women with poor sleep quality. Research Design and Methods: Twenty-nine women with poor sleep quality were recruited as participants randomly assigned into ring fit adventure exergame group (RFA, n = 15) and control group (CON, n = 14). The RFA group received ring fit adventure exergame for 60 min each time, 2 times a week, for 12 weeks. The CON group was not allowed to participate in intervention activities during the study period. Heart rate variability, sleep quality, cortisol, serotonin, and high-sensitive C-reactive protein were measured before and after the 12-week intervention. Results: The Pittsburgh Sleep Quality Index total score in the RFA group was significantly lower compared with the CON group. The value of the standard deviation of normal NN intervals and the root mean square of the successive RR Differences were significantly increased in the RFA group, when compared with the CON group. The change in the logarithm of high frequency (log HF) was significantly higher and change in the logarithm of low frequency to high frequency ratio (log LF/HF) was significantly lower in the RFA group, when compared to the CON group. The change level of serotonin in the RFA group was significantly higher compared with the CON group. Discussion and Implications: The results suggest that somatosensory games might improve sleep quality, increase serotonin level, and decrease sympathetic nerve activities in middle-aged women with poor sleep quality. [ABSTRACT FROM AUTHOR]

Featured Application: This article explores the potential benefits of intervention with acute hypoxia cycling training protocols on player sports performances, including different interventions and supplementations. Training in hypoxic environments enhances endurance, but the various influences of training protocols and supplementation for efficient performance are not yet clear. This systematic review explored the effects of different supplementations and interventions used to optimize the aerobic and anaerobic performance of cyclists. Data were collected from the following sources: PubMed, Google Scholar, EMBASE, WOS, Cochrane Central Register of Controlled Trials, and randomized controlled trials (RCTs). Studies that explored the effects of supplementation or intervention during cycling were selected for analysis. Five studies (67 male cyclists; mean age, 23.74–33.56 years) reported different outcomes from supplementation or intervention during the acute hypoxia of cyclists. Three studies (42 male cyclists; mean age, 25.88–36.22 years) listed the benefits of beetroot juice in preserving SpO2 (pulse oxygen saturation) and enhancing high-intensity endurance performance, effectively preventing the reduction in power output. This systematic review provided evidence that the different effects of ischemic preconditioning (IPC), sildenafil, and beetroot (BR) supplementation and intervention did not present a statistically greater benefit than for normoxia groups, but BR supplementation promoted the benefits of SpO2. Future research should evaluate the duration and higher FiO2 (simulated altitude, hypoxia) levels of hypoxia in training protocols for cyclists. This is important when determining the effectiveness of supplements or interventions in hypoxic conditions and their impact on sports performance, particularly in terms of power output. [ABSTRACT FROM AUTHOR]

In this paper, a general definition of circulating currents for each phase of each paralleled converter with different load sharing is first proposed. Then, based on this definition, the corresponding circulating current index [[gamma].sub.kj] and unbalance rate [[beta].sub.j] for paralleled converter j are proposed to provide one with a quantitative measure about the serious status of power quality. Third, the corresponding general model of circulating currents is also derived for understanding the governing dynamic behavior of circulating currents. Fourth, based on the derived model, the proposed coordinate control strategy is then proposed for different load sharing controls, as well as elimination of circulating currents. Furthermore, a prototype system is also constructed, and the proposed coordinate control is implemented using TMS320F2812 digital signal processor. Both simulation and experimental results indeed show the effectiveness of the proposed coordinate control. Index Terms--Circulating currents, parallel system, three-phase boost rectifiers.

In this paper, definition of the circulating currents of multiphase paralleled converters is first presented, and the circulating-current-generating mechanism is clearly explained. Thus, based on this definition, an averaged model of the circulating current is proposed. It is seen from this model that the circulating current consists of not only the zero-sequence but also the nonzerosequence components. The governing differential equation also shows explicitly the relation between the circulating currents and the affecting factors such as different pulse width-modulation strategies. With this understanding, a simple coordinate control is then presented to reduce the circulating current. The phenomenon of the intrinsic circulating current is also explained. Furthermore, a prototype system is constructed, and the proposed control is implemented using TMS320F2812 DSP. Both simulation and experimental results verify the validity of the proposed theory and control. Index Terms--Circulating current, parallel system, three-phase boost rectifiers.