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Defects in two-dimensional conformal field theories (CFTs) contain signatures of their characteristics. In this work, we analyze entanglement properties of subsystems in the presence of energy and duality defects in the Ising CFT using the density matrix renormalization group (DMRG) technique. In particular, we compute the entanglement entropy (EE) and the entanglement negativity (EN) in the presence of defects. For the EE, we consider the cases when the defect lies within the subsystem and at the edge of the subsystem. We show that the EE for the duality defect exhibits fundamentally different characteristics compared to the energy defect due to the existence of localized and delocalized zero energy modes. Of special interest is the nontrivial ‘finite-size correction’ in the EE obtained recently using free fermion computations [1]. These corrections arise when the subsystem size is appreciable compared to the total system size and lead to a deviation from the usual logarithmic scaling characteristic of one-dimensional quantum-critical systems. Using matrix product states with open and infinite boundary conditions, we numerically demonstrate the disappearance of the zero mode contribution for finite subsystem sizes in the thermodynamic limit. Our results provide further support to the recent free fermion computations, but clearly contradict earlier analytical field theory calculations based on twisted torus partition functions. Subsequently, we compute the logarithm of the EN (log-EN) between two disjoint subsystems separated by a defect. We show that the log-EN scales logarithmically with the separation of the subsystems. However, the coefficient of this logarithmic scaling yields a continuously-varying effective central charge that is different from that obtained from analogous computations of the EE. The defects leave their fingerprints in the subleading term of the scaling of the log-EN. Furthermore, the log-EN receives similar ‘finite size corrections’ like the EE which leads to deviations from its characteristic logarithmic scaling. [ABSTRACT FROM AUTHOR]

This study investigated the effects of creatine and sodium bicarbonate coingestion on mechanical power during repeated sprints. Nine well-trained men (age = 21.6 ± 0.9 yr, stature = 1.82 ± 0.05 m, body mass = 80.1 ± 12.8 kg) participated in a double-blind, placebo-controlled, counterbalanced, crossover study using six 10-s repeated Wingate tests. Participants ingested either a placebo (0.5 g·kg-1 of maltodextrin), 20 g·d-1 of creatine monohydrate + placebo, 0.3 g·kg-1 of sodium bicarbonate + placebo, or coingestion + placebo for 7 days, with a 7-day washout between conditions. Participants were randomized into two groups with a differential counterbalanced order. Creatine conditions were ordered first and last. Indices of mechanical power output (W), total work (J) and fatigue index (W·s-1) were measured during each test and analyzed using the magnitude of differences between groups in relation to the smallest worthwhile change in performance. Compared with placebo, both creatine (effect size (ES) = 0.37-0.83) and sodium bicarbonate (ES = 0.22-0.46) reported meaningful improvements on indices of mechanical power output. Coingestion provided small meaningful improvements on indices of mechanical power output (W) compared with sodium bicarbonate (ES = 0.28-0.41), but not when compared with creatine (ES = -0.21-0.14). Coingestion provided a small meaningful improvement in total work (J; ES = 0.24) compared with creatine. Fatigue index (W·s-1) was impaired in all conditions compared with placebo. In conclusion, there was no meaningful additive effect of creatine and sodium bicarbonate coingestion on mechanical power during repeated sprints. [ABSTRACT FROM AUTHOR]

Background: Optimal prescription of resistance exercise load (kg) is essential for the development of maximal strength. Two methods are commonly used in practice with no clear consensus on the most effective approach for the improvement of maximal strength. Objective: The primary aim of this review was to compare the effectiveness of percentage 1RM (% 1RM) and repetition maximum targets (RM) as load prescription methods for the development of maximal strength. Methods: Electronic database searches of MEDLINE, SPORTDiscus, Scopus, and CINAHL Complete were conducted in accordance with PRISMA guidelines. Studies were eligible for inclusion if a direct measure of maximal strength was used, a non-training control group was a comparator, the training intervention was > 4 weeks in duration and was replicable, and participants were defined as healthy and between the ages of 18–40. Methodological quality of the studies was evaluated using a modified Downs and Black checklist. Percentage change (%) and 95% confidence intervals (CI) for all strength-based training groups were calculated. Statistical significance (p < 0.05) was reported from each study. Results: Twenty-two studies comprising a total of 761 participants (585 males and 176 females) were found to meet the inclusion criteria. 12 studies were returned for % 1RM, with 10 for RM. All studies showed statistically significant improvements in maximal strength in the training groups (31.3 ± 21.9%; 95% CI 33.1–29.5%). The mean quality rating for all studies was 17.7 ± 2.3. Four studies achieved a good methodological rating, with the remainder classified as moderate. Conclusions: Both % 1RM and RM are effective tools for improving maximal strength. % 1RM appears to be a better prescriptive method than RM potentially due to a more sophisticated management of residual fatigue. However, large heterogeneity was present within this data. Lower body and multi-joint exercises appear to be more appropriate for developing maximal strength. Greater consensus is required in defining optimal training prescriptions, physiological adaptations, and training status. [ABSTRACT FROM AUTHOR]

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Hills, SP, Rogerson, DJ. Associatons between self-reported well-being and neuromuscular performance during a professional rugby union season. J Strength Cond Res 32(9): 2498–2509, 2018—Self-reported wellness is often used to monitor fatigue responses to training and competition. Constraints within team sports mean short-form wellness questionnaires are typically preferred to literature-validated documents. This research aimed to assess the relationship between self-reported wellness and neuromuscular (NM) performance during a professional rugby union season, and to identify changes in these parameters over a 12-week period. On the first training day each week, before activity, 37 players rated 5 wellness subscales ("fatigue/vigor," "upper-body soreness," "lower-body soreness," "mood," and "sleep quality/duration") on a 1–5 Likert scale (1 representing the lowest wellness), and 5-repetition countermovement jumps (CMJs) were completed after a warm-up. Each week, total wellness, wellness subscales, and 4 CMJ measures for each participant were calculated as change from baseline. Within-participant correlations were determined between changes in wellness and CMJ measures, whereas week-to week differences and differences from baseline were assessed using Wilcoxon signed-rank tests. Within-participant correlations were compared for players grouped by age and position. Wellness and CMJ scores fluctuated according to physical stress, persisted beneath baseline throughout, and showed declining trends over 12 weeks. Very large (r = 0.7–0.89)/large (r = 0.5–0.69) correlations were identified between wellness and CMJ variables (positive: velocity, dip, time; negative: duration), and each wellness subscale displayed large/very large positive correlations with CMJ velocity. This was true for all subgroups, although subtle differences existed between ages and positions. It was concluded that players' subjective wellness is a useful tool, ideally used within a broader monitoring scheme, for monitoring ongoing NM fatigue, which increased from week to week. [ABSTRACT FROM AUTHOR]

Background: Long-term weight management consists of weight-loss, weight-loss maintenance, and weight-gain stages. Qualitative insights into weight management are now appearing in the literature however research appears to be biased towards explorations of weight-loss maintenance. The qualitative understanding of weight loss, which begets weight-loss maintenance and might establish the experiences and behaviours necessary for successful long-term weight management, is comparatively under-investigated. The aim of this study was to investigate the weight-loss experiences of a sample of participants not aligned to clinical intervention research, in order to understand the weight-loss experiences of a naturalistic sample.Methods: Participants (n = 8) with weight-loss (n = 4) and weight-maintenance experiences (n = 4) were interviewed using a semi-structured interview to understand the weight-loss experience. Interview data was analysed thematically using Framework Analysis and was underpinned by realist meta-theory.Results: Weight loss was experienced as an enduring challenge, where factors that assisted weight loss were developed and experienced dichotomously to factors that hindered it. Participants described barriers to (dichotomous thinking, environments, social pressures and weight centeredness) and facilitators of (mindfulness, knowledge, exercise, readiness to change, structure, self-monitoring and social support) their weight-loss goals in rich detail, highlighting that weight loss was a complex experience.Conclusions: Weight loss was a difficult task, with physical, social, behavioural and environmental elements that appeared to assist and inhibit weight-loss efforts concurrently. Health professionals might need to better understand the day-to-day challenges of dieters in order to provide more effective, tailored treatments. Future research should look to investigate the psycho-social consequences of weight-loss dieting, in particular self-imposed social exclusion and spousal sabotage and flexible approaches to treatment. [ABSTRACT FROM AUTHOR]

Objective: Weight management appears to be multidimensional and complex, and registered nutritionists might work to educate, promote and provide weight-management services to communities, groups and individuals. However, nutrition education might not adequately reflect the weight-management requirements of individuals and groups. The aim of the present study was to investigate if the Association for Nutrition's undergraduate core competency framework for accredited Nutrition degrees sufficiently reflects the weight-management needs and experiences of individuals.Design: A qualitative investigation, conducted within critical realist ontology, was performed to understand the weight-management experiences of dieters and compare these with the Association for Nutrition's accreditation criteria for undergraduate Nutrition degrees.Setting: Framework analysis was used to identify and explain participants' experiences thematically and to compare these with the Association for Nutrition's core competency criteria.Subjects: Participants (n 8) with weight-loss (n 4) and weight-maintenance experiences (n 4) were interviewed using semi-structured interviews to understand weight management at the agential level.Results: Participants described knowledge, exercise, planning, psychological constructs and behaviour-change techniques, determinants of eating and social support as features of weight management. The competency criteria provided clear guidance on all aspects discussed by the group, apart from psychological constructs and behaviour-change techniques and social support.Conclusions: Accredited Nutrition courses might not fully reflect the weight-management needs and experiences of individuals. Nutritionists might require greater knowledge of psychology and behaviour change to better understand and accommodate their clients' weight-management needs. [ABSTRACT FROM AUTHOR]

Tennis is a pan-global sport that is played year-round in both hemispheres. This places notable demands on the physical and psychological preparation of players and included in these demands are nutritional and fluid requirements both of training and match-play. Thus, the purpose of this article is to review nutritional recommendations for tennis. Notably, tennis players do not excel in any particular physiological or anthropometric characteristic but are well adapted in all areas which is probably a result of the varied nature of the training demands of tennis match play. Energy expenditures of 30.9 ± 5.5 and 45.3 ± 7.3 kJ∙min-1 have been reported in women and men players respectively regardless of court surface. Tennis players should follow a habitually high carbohydrate diet of between 6-10 g.kg-1.d-1 to ensure adequate glycogen stores, with women generally requiring slightly less than men. Protein intake guidelines for tennis players training at a high intensity and duration on a daily basis should be ~1.6 g.kg-1.d-1 and dietary fat intake should not exceed 2 g.kg-1.d-1. Caffeine in doses of 3 mg.kg-1 provides ergogenic benefit when taken before and/or during tennis match play. Depending on environmental conditions, sweat rates of 0.5 to and over 5 L.hr-1 and sodium losses of 0.5 - 1.8 g have been recorded in men and women players. 200 mL of fluid containing electrolytes should be consumed every change-over in mild to moderate temperatures of < 27°C but in temperatures greater than 27°C players should aim for = 400 mL. 30-60 g.hr-1 of carbohydrate should be ingested when match play exceeds 2 hours. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare kinetics and kinematics of 2 lower-body free-weight exercises, calculated from concentric and propulsion subphases, across multiple loads. Sixteen strength-trained men performed back squat 1 repetition maximum (1RM) tests (visit 1), followed by 2 incremental back squat and jump squat protocols (visit 2) (loads = 0% and 30-60%, back squat 1RM). Concentric phase and propulsion phase force-time-displacement characteristics were derived from force plate data and compared using analysis of variance and Hedges' g effect sizes. Intrasession reliability was calculated using intraclass correlation coefficient (ICC) and coefficient of variation (CV). All dependent variables met acceptable reliability (ICC >0.7; CV < 10%). Statistically significant 3-way interactions (load × phase × exercise) and 2-way main effects (phase × exercise) were observed for mean force, velocity (30-60% 1RM), power, work, displacement, and duration (0%, 30-50% 1RM) (p < 0.05). A significant 2-way interaction (load × exercise) was observed for impulse (p < 0.001). Jump squat velocity (g = 0.94-3.80), impulse (g = 1.98-3.21), power (g = 0.84-2.93), and work (g = 1.09-3.56) were significantly larger across concentric and propulsion phases, as well as mean propulsion force (g = 0.30-1.06) performed over all loads (p < 0.001). No statistically significant differences were observed for mean concentric force. Statistically longer durations (g = 0.38-1.54) and larger displacements (g = 2.03-4.40) were evident for all loads and both subphases (p < 0.05). Ballistic, lower-body exercise produces greater kinetic and kinematic outputs than nonballistic equivalents, irrespective of phase determination. Practitioners should therefore use ballistic methods when prescribing or testing lower-body exercises to maximize athlete's force-time-displacement characteristics. [ABSTRACT FROM AUTHOR]

Background: Physical activity has been cited as a potential symptomatic treatment option for people living with dementia. At present, much of the research concerning physical activity and dementia considers older adults, and there are several review articles summarising the evidence in this area. Less is known about physical activity for younger people with dementia, despite the marked differences in needs and preferences between the two groups. The aim of this scoping review is to systematically explore and critically appraise the current state of the evidence regarding physical activity for people with young-onset dementia and carers. Methods: Several electronic databases (i.e. MEDLINE, SPORTDiscus, CINAHL, Cochrane Library, PsycINFO, Applied Social Sciences Index & Abstracts (ASSIA) and Scopus), grey literature (i.e. NICE Evidence Search (UK) and targeted international organisations e.g. Alzheimer’s Society (UK), Age UK, Young Dementia UK, Alzheimer’s Association (USA), Dementia Australia) and trial registries (i.e. UK Clinical Trials Gateway, International Clinical Trials Registry Platform and EU Clinical Trials Register) will be searched for published and unpublished evidence regarding physical activity for people with young-onset dementia and carers. Studies included in the review will be subjected to a narrative synthesis to explore similarities and differences, both within and between studies, to identify patterns and themes and to postulate explanations for research findings (e.g. how and why certain interventions or programmes have worked (or not); factors that might have influenced the findings ). Discussion: This will be the first review to systematically explore and critically appraise the current state of the evidence regarding physical activity for people with young-onset dementia and carers. It is hoped that findings from this review will be used to inform the development of future physical activity interventions, to serve as a basis for consultation with key stakeholders and to identify appropriate outcome measures relevant to people with young-onset dementia and carers. Systematic review registration: At present, scoping reviews are not eligible for registration on the international prospective register of systematic reviews (i.e. PROSPERO). [ABSTRACT FROM AUTHOR]

To date, little is known about overreaching (OR) and the overtraining syndrome (OTS) in strength sports and resistance training (RT) populations. However, the available literature may elucidate the occurrence of both conditions in these populations. A scoping review was conducted. SPORTDiscus, Scopus and Web of Science were searched in a robust and systematic manner, with relevant articles analysed. 1170 records were retrieved during an initial search, with a total of 47 included in the review. Two broad themes were identified during data extraction: 1) overreaching in strength sports; 2) overreaching and overtraining syndrome in RT. Short-term periods of OR achieved with either high-volume or high-intensity RT can elicit functional OR (FOR) but there is also evidence that chronic high-volume and/or intensity RT can lead to non-functional overreaching (NFOR). There is minimal evidence to suggest that true OTS has occurred in strength sports or RT based on the studies entered during this review. More research is needed to develop robust guiding principles for practitioners. Additionally, due to the heterogeneous nature of the existing literature, future research would benefit from the development of practical tools to identify and diagnose the transition from FOR to NFOR, and subsequently OTS in strength athletes and RT populations. RT: Resistance training; OR: Overreaching; FOR: Functional overreaching; NFOR: Non-functional overreaching; OTS: Overtraining syndrome; WP: Weightlifting performance [ABSTRACT FROM AUTHOR]