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Dose-Response Relationships between Diet Quality and Mortality among Frail and Non-Frail Older Adults: A Population-Based Kyoto-Kameoka Prospective Cohort Study.

Although better diet quality is inversely associated with mortality risk, the association between diet quality and mortality remains unclear in frail and non-frail older adults. Thus, we aimed to examine this association in older Japanese adults. A prospective cohort study. We used the data of 8,051 Japanese older adults aged ≥65 years in the Kyoto-Kameoka study. Dietary intake was estimated using a validated food frequency questionnaire. Diet quality was evaluated by calculating the adherence scores to the Japanese Food Guide Spinning Top (range, 0 [worst] to 80 [best]), which were stratified into quartiles. Frailty status was assessed using the validated self-administered Kihon Checklist (KCL) and the Fried phenotype (FP) model. Survival data were collected between February 15, 2012 and November 30, 2016. Statistical analysis was performed using the multivariate Cox proportional hazard analysis and the spline model. During the median 4.75-year follow-up (36,552 person-years), we recorded 661 deaths. After adjusting for confounders, compared with the bottom adherence score quartile, the top quartile was associated with lower hazard ratio (HR) of mortality in frailty (HR, 0.73; 95% confidence interval [CI], 0.54-1.00) and non-frailty, as defined by the KCL (HR, 0.72; 95% CI, 0.52-1.01). In the spline model, regardless of frailty status defined by the KCL and FP model, adherence score showed a strongly dose-dependent inverse association with mortality up to approximately 55 points; however, no significant differences were observed thereafter. This association was similar to the results obtained in individuals with physical, cognitive, and depression as domains of KCL in the spline model. Our findings demonstrate an L-shaped association between diet quality and mortality in both frail and non-frail individuals. This study may provide important knowledge for improving poor diet quality in older individuals with frailty or domains of frailty.

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Genetic differentiation of water penny beetles may be associated with the formation process of the ancient Lake Biwa

AbstractBackgroundWater flow is one of several factors that determine the habitats of aquatic insects. The conversions of stagnant (lentic) and running (lotic) water are physiologically and ecologically constrained. In general, aquatic insect species only occur in one of these environments. ThoughEubrianax ramicornis(Coleoptera: Psephenidae) usually resides in rivers, however, it is also known to occur near the shores of Lake Biwa in Japan. Here, we investigated the genetic differences between the two Eubrianax species of Lake Biwa and its inflowing rivers, and other regions of Japan for the first time. Lake Biwa is an ancient lake and about four million years old. Though over 60 endemic species were described from Lake Biwa, they are mostly fish and molluscs, with only two species of aquatic insects. There are few reports of endemic aquatic insects in other ancient lakes, too. Discussion of the endemism of Eubrianax and its promoting factors is expected to provide insights into the evolution of aquatic insects in ancient lakes.MethodsWe surveyed and morphologically identified psephenid larvae in Lake Biwa and its inflowing rivers during the summers of 2017 and 2018 (Hayashi, 2009: Hayashi & Sota, 2009). We conducted phylogenetic analyses of two regions of COI and estimated the ages of population divergence based on fossil records ofEubrianaxbeetles in Lake Biwa as well as those of previously reported populations in other regions. We also analyzed two COI regions of theE. ramicornishaplotypes in Lake Biwa.ResultsFour psephenid species were identified among the samples collected in Lake Biwa and its inflowing rivers. Of these,E. ramicorniswas collected only at the Lake Biwa shore whereas its congenericE. granicolliswas collected only from the rivers inflowing the lake. The phylogenetic analyses showed thatE. ramicornisof Lake Biwa were clearly differentiated from those in previously reported regions and this divergence was estimated to have occurred 1.40 MYA. At that time, there was no lake at the location of present-day Lake Biwa. It is thought that rivers and their dammed flood plains to the east, with gravel and sand supplied by the rising Suzuka Mountains further to the east. Such an environments is preferable forE. ramicornisand they were thought to have become isolated from the surrounding rivers during the formation of Lake Biwa. On the contrary, there was no genetic differentiation between theE. granicollispopulation at the Lake Biwa inflow rivers and those elsewhere. Hence,E. granicollismight have migrated to the Lake Biwa watershed later thanE. ramicornisand maintained gene flow over a wide area. The genetic differentiation ofE. ramicornisreported here for the first time suggests that a species with a wide distribution may rather be evolving endemic to Lake Biwa. Reports on the endemism of aquatic insects in ancient lakes are scarce. This study is expected to bring new perspectives to the study of insect evolution in ancient lakes.

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Classification of four pitching styles in Japanese baseball players

This study aimed to provide normative biomechanical data of baseball delivery styles and to verify an appropriate criterion for quantitatively classifying baseball pitches into four delivery styles. In total, 74 pitches were visually identified by seven coaches into 24 overhand (OS), 17 three-quarter (TS), 21 sidearm (SS) and 12 underhand (US) deliveries. The accuracies of the classifications of the pitches using the arm slot angle ( θAS) and using the combination of trunk lateral tilt ( θT) and upper arm elevation ( θA) angles at release were compared. Average values for θAS were 53.9°, 31.5°, 5.8°, and −34.8° in the OS, TS, SS and US; corresponding values for θT were 31.9°, 15.4°, −0.9°, and −40.1°; and for θA were 39.8°, 16.1°, −6.3°, and−43.0°. Both variables ( θAS and the average of θ'T and θ'A, which corresponded to the projection of each point on the regression line) correctly classified the delivery styles, but the accuracy of the classification using θAS (96%) was higher than that using the average of θ'T and θ'A (89%). There were fewer and smaller overlaps of the ranges of pitches classified using θAS (only 6 pitches between TS and SS (14.9° to 23.0°), which can be considered a buffer zone) compared to the average of θ'T and θ'A. Consequently, θAS seems the most appropriate for classifying baseball pitches into the four delivery styles. The separation points between the four styles were marked by θAS values of 45° (between OS and TS), 19° (between TS and SS) and −13° (between SS and US).

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Prediction of Service Performance Based on Physical Strength in Elite Junior Tennis Players.

In tennis, service requires a variety of complicated movements. Given the importance of taking the initiative to obtain points in a tennis match, it is crucial to make full use of speed and spin rate of service. Generally, a service that requires a higher spin rate would slow down, and a service that has increased speed would have a decreased spin rate. For players who are disadvantaged in height, although controlling spin rate is essential, slowing down service speed should be avoided. For these players, the challenge of service is to improve the speed without decreasing the spin rate. Players must also be trained to build physical strength required for this skill. It is not uncommon to work on physical training without a racket; however, few studies have reported on the effects of cultivated physical strength on on-court tennis performance. Therefore, this study aimed to propose physical measurements that could be used as indices to improve service performance in 58 elite Japanese junior male players. To test service performance, we used TrackMan tennis radar device to assess speed, spin rate, impact height, and impact depth. To test physical strength, we measured 5- and 20-m sprint, broad jump, medicine ball throw (forward, backward). We used a significant multiple regression equation to predict the first service speed obtained from the broad jump and the Medicine ball throw (backward). Additionally, a strong correlation was obtained between the predicted and measured values. In addition to physical strength, we suggest that the depth of the impact point (taking the hitting point forward toward the net) is important for improving the first service speed. However, we were not able to identify the physical strength test items that improve service spin rate. Other item should be examined in the future to determine the physical strength associated with spin rate. This result could help connect physical training and service performance.

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Change in dynamic postural control after a training program in collegiate soccer players with unilateral chronic ankle instability.

Improving dynamic postural stability after lateral ankle sprain due to chronic ankle instability helps prevent recurrence, and changes in dynamic postural stability can be assessed with the Star Excursion Balance Test. To date, no studies have examined the change in Star Excursion Balance Test score after the end of a balance training program or whether chronic ankle instability affects the rate of change. To examine the effect of chronic ankle instability on changes in Star Excursion Balance Test. score over time after a balance training program. Fifteen collegiate soccer players with chronic ankle instability selected with the Cumberland Ankle Instability Tool and ultrasonography. Participants completed a 6-week balance training program. We assessed the Star Excursion Balance Test 5 times (before and immediately after the program and 2, 4, and 6 weeks later) and examined differences in the duration of training effects by a 2-way analysis of variance, with Bonferroni correction for post hoc comparisons to explain any significant interactions. The significance level for all analyses was set at P<0.05. We performed statistical analyses with SPSS v. 25. Analysis of the posterolateral and posteromedial scores in Star Excursion Balance Test showed a significant effect of time. Post hoc analysis of the posterolateral score showed that for each leg, participants reached significantly farther after the program than before (P=0.012). The posterolateral scores at 2, 4, and 6 weeks after the training program did not differ from before the program, but the posteromedial score was significantly improved immediately after the program (P=0.008) and also 2 (P=0.004) and 4 weeks later (P=0.006). A 6-week balance training program to improve dynamic postural control can improve posterolateral and posteromedial scores in people with chronic ankle instability, and the improvements in posteromedial are still present 4 weeks after program completion.

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The effects of using a combination of static stretching and aerobic exercise on muscle tendon unit stiffness and strength in ankle plantar-flexor muscles

ABSTRACT The purpose of the present study was to investigate the effects of using a combination of static stretching and aerobic exercise on muscle tendon unit stiffness and muscle strength in the ankle plantar-flexor muscles. Fifteen healthy males (23.3 ± 2.7 years, 170.3 ± 6.5 cm, 64.9 ± 8.7 kg) received three different interventions, in random order. Intervention 1 received 10 min of aerobic exercise after five cycles of one minute of static stretching. Intervention 2 received 10 min of aerobic exercise before the static stretching. Intervention 3 received 5 min of aerobic exercise both before and after the static stretching. The range of motion of ankle dorsiflexion, stretch tolerance, muscle tendon unit stiffness, peak torque of ankle plantarflexion, and the amplitude of electromyography were measured. In all interventions, the range of motion and stretch tolerance significantly increased (p < 0.05), but muscle tendon unit stiffness decreased significantly for all interventions (p < 0.05). Peak torque of ankle plantar flexion and amplitude of electromyography significantly increased for Interventions 1 and 3 (p < 0.05), while these significantly decreased for Intervention 2 (p < 0.05). These data indicated that range of motion and stretch tolerance were increased, but muscle tendon unit stiffness was decreased regardless of the order of static stretching and aerobic exercise. Aerobic exercise after static stretching increased the peak torque and amplitude of electromyography.

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The relationship between free-throw accuracy and performance variables in male wheelchair basketball players

We investigated the relationship between the free-throw accuracy and performance variables among fourteen elite male wheelchair basketball players. Participants performed 20 basketball free-throws. Basketball performance variables were the phases of the pre-shoot routine: (a) time taken, (b) minimum angle when taking the ball back, (c) angle at ball release, (d) angular displacement during the forward arm swing, and (e) angular velocity at ball release on the elbow, shoulder, and hip. A significant negative correlation was observed between the free-throw accuracy and mean pre-shot time, suggesting that participants with a shorter pre-shot time showed a higher free-throw accuracy. In addition, a significant negative correlation was found between the free-throw accuracy and variability of angular velocity of the hip at the time of ball release, indicating that the consistency of hip movement is an important factor in free-throw accuracy. In contrast, there were no relationship between the free-throw accuracy and player’s classification point defined as International Wheelchair Basketball Federation, and experience of wheelchair basketball. These data suggest that the routine duration and trunk movement are related to free-throw accuracy in wheelchair basketball.

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