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  • Ladefoged Ortiz posted an update 6 days, 17 hours ago

    Walking is a complex task requiring the interplay of neuromuscular, sensory, and cognitive functions. Owing to the age-related decline in cognitive and physical functions, walking may be compromised in older adults, for cognitive functions, especially poor performance in executive functions, is associated with slow walking speed. Hence, the aim of this study was to investigate the associations between different subdomains of executive functions and physical functions and whether the associations found differ between men and women. Multiple linear regression analysis was performed on data collected from 314 community-dwelling older adults who did not meet physical activity guidelines but had intact cognition. Our results showed that, while executive functions were associated with gait and lower extremity functioning, the associations depended partly on the executive process measured and the nature of the physical task. Moreover, the associations did not differ between the sexes.The authors investigated the association between vision impairment and physical activity among older adults from low- and middle-income countries. Visual acuity was measured using the tumbling ElogMAR chart, and vision impairment was defined as visual acuity worse than 6/18 (0.48 logMAR) in the better seeing eye. Physical activity was assessed by the Global Physical Activity Questionnaire. Multivariable logistic regression and meta-analysis were conducted to assess associations. The sample included 34,129 individuals aged 50-114 years (mean [SD] age 62.4 [16.0] years; 47.9% male). After adjustment for confounders, near vision impairment was not significantly associated with low physical activity, but far vision impairment showed a significant association (odds ratio = 1.32; 95% confidence interval [1.17, 1.49], I2 = 0.0%). Far vision impairment was dose-dependently associated with low physical activity (e.g., severe [ less then 6/10] vs. no [≥6/12] far vision impairment; odds ratio = 1.80; 95% confidence interval [1.03, 3.15]). Interventions to address low levels of physical activity in the visually impaired in low- and middle-income countries should target those with far vision impairment.Estimating center of mass (COM) through sensor measurements is done to maintain walking and standing stability with exoskeletons. The authors present a method for estimating COM kinematics through an artificial neural network, which was trained by minimizing the mean squared error between COM displacements measured by a gold-standard motion capture system and recorded acceleration signals from body-mounted accelerometers. A total of 5 able-bodied participants were destabilized during standing through (1) unexpected perturbations caused by 4 linear actuators pulling on the waist and (2) volitionally moving weighted jars on a shelf. Each movement type was averaged across all participants. The algorithm’s performance was quantified by the root mean square error and coefficient of determination (R2) calculated from both the entire trial and during each perturbation type. Throughout the trials and movement types, the average coefficient of determination was 0.83, with 89% of the movements with R2 > .70, while the average root mean square error ranged between 7.3% and 22.0%, corresponding to 0.5- and 0.94-cm error in both the coronal and sagittal planes. COM can be estimated in real time for balance control of exoskeletons for individuals with a spinal cord injury, and the procedure can be generalized for other gait studies.This study examined para swimmers’ athlete development experiences from the perspectives and reflections of athletes, and parents of athletes, with a focus on the constraints and challenges experienced. Guided by interpretive phenomenological analysis, 12 participants engaged in the interview process (seven parents and five athletes). Five themes were identified fundamental skill development, personal connection, coaching, classification, and connecting with others “like me.” Through a discussion of the differences in development experiences between the participants in this study and the current literature on athlete development, the authors highlight areas of concern in applying a non-para-specific athlete development model to para swimmers. This study identifies several areas of consideration in the future design of a para athlete development framework or model.The purpose of this study was to examine the effects of two pedagogical strategies in adapted physical education (hybrid virtual/real vs. AZD8186 purchase conventional) on fundamental movement skills (FMS) in children with intellectual disability age 7-10 years. Children with intellectual disability (N = 24) were randomly assigned to either the hybrid (experimental group) or the conventional (control group) group and were evaluated across 10 weeks. The hybrid program was based on virtual and real game situations, while the conventional program was based on adapted sports. FMS were evaluated using the Test of Gross Motor Development-2 at pre- and postprogram for both groups. Both programs significantly improve locomotor skills, with significantly better improvement in the experimental group. However, a significant improvement was observed only among the experimental group for object-control skills and gross motor quotient. Based on these results, a hybrid program may be considered for FMS improvement.

    The broad aim of sport-science research is to enhance the performance of coaches and athletes. Despite decades of such research, it is well documented that sport-science research lacks empirical evidence, and critics have questioned its scientific methods. Moreover, many have pointed to a research-practice gap, whereby the work undertaken by researchers is not readily applied by practitioners. The aim of this study was to use a systems thinking analysis method, causal loop diagrams, to understand the systemic issues that interact to influence the quality of sport-science research.

    A group model-building process was utilized to develop the causal loop diagram based on data obtained from relevant peer-reviewed literature and subject-matter experts.

    The findings demonstrate the panoply of systemic influences associated with sport-science research, including the existence of silos, a focus on quantitative research, archaic practices, and an academic system that is incongruous with what it actually purports to achieve.

    The emergent outcome of the interacting components is the creation of an underperforming sport-science research system, as indicated by a lack of ecological validity, translation to practice, and, ultimately, a research-practice gap.

    The emergent outcome of the interacting components is the creation of an underperforming sport-science research system, as indicated by a lack of ecological validity, translation to practice, and, ultimately, a research-practice gap.Supplementing postexercise carbohydrate (CHO) intake with protein has been suggested to enhance recovery from endurance exercise. The aim of this study was to investigate whether adding protein to the recovery drink can improve 24-hr recovery when CHO intake is suboptimal. In a double-blind crossover design, 12 trained men performed three 2-day trials consisting of constant-load exercise to reduce glycogen on Day 1, followed by ingestion of a CHO drink (1.2 g·kg-1·2 hr-1) either without or with added whey protein concentrate (CHO + PRO) or whey protein hydrolysate (CHO + PROH) (0.3 g·kg-1·2 hr-1). Arterialized blood glucose and insulin responses were analyzed for 2 hr postingestion. Time-trial performance was measured the next day after another bout of glycogen-reducing exercise. The 30-min time-trial performance did not differ between the three trials (M ± SD, 401 ± 75, 411 ± 80, 404 ± 58 kJ in CHO, CHO + PRO, and CHO + PROH, respectively, p = .83). No significant differences were found in glucose disposal (area under the curve [AUC]) between the postexercise conditions (364 ± 107, 341 ± 76, and 330 ± 147, mmol·L-1·2 hr-1, respectively). Insulin AUC was lower in CHO (18.1 ± 7.7 nmol·L-1·2 hr-1) compared with CHO + PRO and CHO + PROH (24.6 ± 12.4 vs. 24.5 ± 10.6, p = .036 and .015). No difference in insulin AUC was found between CHO + PRO and CHO + PROH. Despite a higher acute insulin response, adding protein to a CHO-based recovery drink after a prolonged, high-intensity exercise bout did not change next-day exercise capacity when overall 24-hr macronutrient and caloric intake was controlled.This study described the clustering patterns of moderate to vigorous physical activity and sedentary time (ST) according to handgrip strength and investigated the association between identified clusters of fat and lean mass in older adults from southern Brazil. Objective measures were used for moderate to vigorous physical activity, ST, and body composition outcomes. Two-step cluster and linear regression analyses were conducted according to handgrip strength. Three clusters were identified all-day sitters, sitters, and active sitters. The prevalence of clusters in the low-strength group was 58.2%, 22.8%, and 19.0%, respectively, while the prevalence of clusters in the high-strength group was 42.1%, 34.8%, and 23.1%, respectively. All-day sitters had 2.6% more fat mass than active sitters with low strength. High levels of ST characterized all cluster profiles; low strength, lack of moderate to vigorous physical activity, and high ST levels among older adults may indicate a subpopulation at a greater risk of overweight and obesity-related diseases.Recent research [Wang et al., Nature 581, 184-189 (2020)] indicates nitric acid (NA) can participate in sulfuric acid (SA)-ammonia (NH3) nucleation in the clean and cold upper free troposphere, whereas NA exhibits no obvious effects at the boundary layer with relatively high temperatures. Herein, considering that an SA-dimethylamine (DMA) nucleation mechanism was detected in megacities [Yao et al., Science 361, 278-281 (2018)], the roles of NA in SA-DMA nucleation are investigated. Different from SA-NH3 nucleation, we found that NA can enhance SA-DMA-based particle formation rates in the polluted atmospheric boundary layer, such as Beijing in winter, with the enhancement up to 80-fold. Moreover, we found that NA can promote the number concentrations of nucleation clusters (up to 27-fold) and contribute 76% of cluster formation pathways at 280 K. The enhancements on particle formation by NA are critical for particulate pollution in the polluted boundary layer with relatively high NA and DMA concentrations.The CMT2 and RNA-directed DNA methylation (RdDM) pathways have been proposed to separately maintain CHH methylation in specific regions of the Arabidopsis thaliana genome. Here, we show that dysfunction of the chromatin remodeler DDM1 causes hundreds of genomic regions to switch from CMT2 dependency to RdDM dependency in DNA methylation. These converted loci are enriched at the edge regions of long transposable elements (TEs). Furthermore, we found that dysfunction in both DDM1 and RdDM causes strong reactivation of TEs and a burst of TE transposition in the first generation of mutant plants, indicating that the DDM1 and RdDM pathways together are critical to maintaining TE repression and protecting genomic stability. Our findings reveal the existence of a pathway conversion-based backup mechanism to guarantee the maintenance of DNA methylation and genome integrity.