Reionization and cosmic dawn astrophysics from the Square Kilometre Array:impact of observing strategies

Interferometry of the cosmic 21-cm signal is set to revolutionize our understanding of the epoch of reionization (EoR) and the cosmic dawn (CD). The culmination of ongoing efforts will be the upcoming Square Kilometre Array (SKA), which will provide tomography of the 21-cm signal from the first billion years of our Universe. Using a galaxy formation model informed by high-z luminosity functions, here we forecast the accuracy with which the first phase of SKA-low (SKA1-low) can constrain the properties of the unseen galaxies driving the astrophysics of the EoR and CD. We consider three observing strategies: (i) deep (1000 h on a single field); (ii) medium-deep (100 h on 10 independent fields); and (iii) shallow (10 h on 100 independent fields). Using the 21-cm power spectrum as a summary statistic, and conservatively only using the 21-cm signal above the foreground wedge, we predict that all three observing strategies should recover astrophysical parameters to a fractional precision of 3c0.1-10 per cent. The reionization history is recovered to an uncertainty of \u394z 7e 0.1 (1\u3c3 ) for the bulk of its duration. The medium-deep strategy, balancing thermal noise against cosmic variance, results in the tightest constraints, slightly outperforming the deep strategy. The shallow observational strategy performs the worst, with up to an 3c10-60 per cent increase in the recovered uncertainty. We note, however, that non-Gaussian summary statistics, tomography, as well as unbiased foreground removal would likely favour the deep strategy

Interpreting magnitude of change in strength and conditioning: effect size selection, threshold values and Bayesian updating.

The magnitude of change following strength and conditioning (S&C) training can be evaluated comparing effect sizes to threshold values. This study conducted a series of meta-analyses and compiled results to identify thresholds specific to S&C, and create prior distributions for Bayesian updating. Pre- and post-training data from S&C interventions were translated into standardised mean difference (SMDpre) and percentage improvement (%Improve) effect sizes. Four-level Bayesian hierarchical meta-analysis models were conducted to compare effect sizes, develop prior distributions, and estimate 0.25-, 0.5-, and 0.75-quantiles to determine small, medium, and large thresholds respectively. Data from 643 studies comprising 6574 effect sizes were included in the analyses. Large differences in distributions for both SMDpre and %Improve were identified across outcome domains (strength, power, jump and sprint performance), with analyses of the tails of the distributions indicating potential large overestimations of SMDpre values. Future evaluations of S&C training will be improved using Bayesian approaches featuring the information and priors developed in this study. To facilitate an uptake of Bayesian methods within S&C, an easily accessible tool employing intuitive Bayesian updating was created. It is recommended that the tool and specific thresholds be used instead of isolated effect size calculations and Cohen's generic values when evaluating S&C training

A Novel Approach to 1RM Prediction Using the Load-Velocity Profile: A Comparison of Models

The study aim was to compare different predictive models in one repetition maximum (1RM) estimation from load-velocity profile (LVP) data. Fourteen strength-trained men underwent initial 1RMs in the free-weight back squat, followed by two LVPs, over three sessions. Profiles were constructed via a combined method (jump squat (0 load, 30–60% 1RM) + back squat (70–100% 1RM)) or back squat only (0 load, 30–100% 1RM) in 10% increments. Quadratic and linear regression modeling was applied to the data to estimate 80% 1RM (kg) using 80% 1RM mean velocity identified in LVP one as the reference point, with load (kg), then extrapolated to predict 1RM. The 1RM prediction was based on LVP two data and analyzed via analysis of variance, effect size (g/), Pearson correlation coefficients (r), paired t-tests, standard error of the estimate (SEE), and limits of agreement (LOA). p < 0.05. All models reported systematic bias < 10 kg, r > 0.97, and SEE < 5 kg, however, all linear models were significantly different from measured 1RM (p = 0.015 <0.001). Significant differences were observed between quadratic and linear models for combined (p < 0.001; = 0.90) and back squat (p = 0.004, = 0.35) methods. Significant differences were observed between exercises when applying linear modeling (p < 0.001, = 0.67–0.80), but not quadratic (p = 0.632–0.929, = 0.001–0.18). Quadratic modeling employing the combined method rendered the greatest predictive validity. Practitioners should therefore utilize this method when looking to predict daily 1RMs as a means of load autoregulation

Which treatments are most effective for common tendinopathies? A systematic review and network meta-analysis protocol.

This is a preprint for a protocol. The purpose of the study described by the protocol was to compare the effectiveness of different treatment classes across a range of tendinopathies and outcomes, to better establish a treatment hierarchy. Where sufficient data were obtained, the potential for covariates - including patient demographics and condition specifics (e.g. symptom severity) - to explain statistical heterogeneity was explored

Comparison of exercise therapies across multiple tendinopathies: a systematic review and network meta-analysis protocol.

This is a preprint for a protocol. The study described by the protocol aimed to use network structures to compare exercise treatments and treatment classes in attempts to identify a treatment hierarchy. Additionally, the large amount of data synthesised was used to explore relevant factors that may explain statistical heterogeneity

The effect of dose components on resistance exercise therapies for tendinopathy management: a systematic review and meta-analysis.

The purpose of this study was to investigate potential moderating effects of resistance exercise dose components including intensity, volume and frequency, for the management of common tendinopathies. The research was undertaken through a systematic review and meta-analysis, comprising an extensive search of databases and trial registries. Eligibility criteria for selecting studies included randomised and non-randomised controlled trials investigating resistance exercise as the dominant treatment class and reporting sufficient information regarding at least two components of exercise dose (intensity, frequency, volume). Non-controlled standardised mean difference effect sizes were calculated across a range out outcome domains and combined with Bayesian hierarchical meta-analysis models for domains generating large (disability; function; pain) and small (range of motion; physical function capacity; and quality of life) effect size values. Meta-regressions were used to estimate differences in pooled mean values across categorical variables quantifying intensity, frequency and volume. Ninety-one studies presented sufficient data to be included in meta-analyses, comprising 126 treatment arms (TAs) and 2965 participants. Studies reported on five tendinopathy locations (Achilles: 39 TAs, 31.0%; rotator cuff: 39 TAs, 31.0%; lateral elbow: 25 TAs, 19.8%; patellar: 19 TAs, 15.1%; and gluteal: 4 TAs, 3.2%). Meta-regressions provided consistent evidence of greater pooled mean effect sizes for higher intensity therapies comprising additional external resistance compared to body mass only (large effect size domains: 0.39 [95% CrI: 0.00 to 0.82; p = 0.976]; small effect size domains (0.09 [95% CrI: -0.20 to 0.37; p = 0.723]) when data were combined across tendinopathy locations or analysed separately. Consistent evidence of greater pooled mean effect sizes was also identified for the lowest frequency (less than daily) compared with mid (daily) and high frequencies (more than daily) for both large effect size domain ( -0.66 [95% CrI: -1.2 to -0.19; p >0.999]; -0.54 [95% CrI:-0.99 to -0.10; p >0.999]) and small effect size domains ( -0.51 [95% CrI: -0.78 to -0.24; p >0.999]; -0.34 [95% CrI: -0.60 to -0.06; p = 0.992]) when data were combined across tendinopathy locations or analysed separately. Minimal and inconsistent evidence was obtained for differences for a moderating effect of training volume. The study concluded that resistance exercise dose is poorly reported within the tendinopathy management literature. However, this large meta-analysis identified some consistent patterns indicating greater efficacy on average with therapies prescribing higher intensities (through the inclusion of additional external loads) and lower frequencies, potentially creating stronger stimuli and facilitating adequate recovery

The effect of dose on resistance exercise therapies for tendinopathy: a systematic review and meta-analysis protocol.

This is a preprint for a protocol. The purpose of the study described by the protocol was to investigate the effect of resistance exercise dose across multiple common tendinopathies (rotator cuff, lateral elbow, patellar or Achilles), where the frequency, volume and intensity can be accurately quantified. By combining a large data set with contemporary meta-analysis and meta-regression approaches (including relevant covariates within models), the systematic review attempted to explore statistical heterogeneity and better assess potential dose-response relationships that may exist. Where placebo and no-treatment arms were included, these studies were used to reduce heterogeneity and provide sensitivity analyses to support or refute analyses with larger, but more complex data

Empirically derived guidelines for interpreting the effectiveness of exercise therapy for tendinopathies: a protocol.

This is a preprint for a protocol. The aim of the study described by the protocol was to perform a large synthesis of the available research investigating exercise therapy for tendinopathies, creating empirically derived thresholds to benchmark interventions and explore potential differences across tendinopathy types and outcome domains

Exercise therapy for tendinopathy: a scoping review mapping interventions and outcomes.

The aim of this research was to comprehensively map exercise interventions and outcomes across all tendinopathies. The study took the form of a scoping review. Eligibility criteria (PCC) included: 1) participants - any age or gender, with any tendinopathy; 2) concept - supervised or unsupervised exercise, of any type or format, delivered by any professional and any outcome used to evaluate any exercise intervention; 3) context - any setting in any country listed as very high on the human development index. The study used nine databases, four trial registries and six grey literature sources. At least two reviewers independently conducted title, abstract and full text screening. Data extraction was conducted using a bespoke tool developed for this review, informed by the TIDieR checklist and ICON health-related domains, to interpret exercise reporting and outcomes across included studies. Extracted data from 555 included studies from 31 countries incorporated 25,490 participants with mean study ages ranging from 15-65 years. A range of exercise interventions including strengthening, flexibility, aerobic, proprioceptive, and motor control were identified; showing rotator cuff-related shoulder pain, Achilles, patellar and lateral elbow tendinopathies were most studied. A range of health-related domains were measured by numerous outcome tools, with little consistency within domains or tendinopathies. Reporting of participant characteristics, interventions and adherence was highly variable. This first comprehensive map of exercise and outcomes for tendinopathy has identified four recommendations to be considered for future tendinopathy research: 1) Specific robust high quality research study designs; (2) Comprehensive research reporting; 3) Patient/practitioner lived experience; and 4) comprehensive high quality evidence synthesis

Effect of resistance exercise dose components for tendinopathy management: a systematic review with meta-analysis.

The objective of this study was to investigate potential moderating effects of resistance exercise dose components - including intensity, volume and frequency - for the management of common tendinopathies. The study was conducted through a systematic review with meta-analysis and meta-regressions, using sources that included (but were not limited to) MEDLINE, CINAHL, SPORTDiscus, ClinicalTrials.gov and the ISRCTN Registry. Selection criteria were based on randomised and non-randomised controlled trials investigating resistance exercise as the dominant treatment class, reporting sufficient information regarding two or more components of exercise dose. A total of 110 studies were included in meta-analyses (148 treatment arms (TAs), 3953 participants), reporting on five tendinopathy locations (rotator cuff: 48 TAs; Achilles: 43 TAs; lateral elbow: 29 TAs; patellar: 24 TAs; gluteal: 4 TAs). Meta-regressions provided consistent evidence of greater pooled mean effect sizes for higher intensity therapies comprising additional external resistance compared to body mass only (large effect size domains: βBodyMass:External = 0.50 [95% CrI: 0.15 to 0.84; p = 0.998]; small effect size domains βBodyMass:External = 0.04 [95% CrI: -0.21 to 0.31; p = 0.619]) when combined across tendinopathy locations or analysed separately. Greater pooled mean effect sizes were also identified for the lowest frequency (less than daily) compared with mid (daily) and high frequencies (more than once per day) for both effect size domains, when combined or analysed separately (p ≥ 0.976). Evidence for associations between training volume and pooled mean effect sizes was minimal and inconsistent. The study found that resistance exercise dose is poorly reported within tendinopathy management literature. However, this large meta-analysis identified some consistent patterns indicating greater efficacy on average with therapies prescribing higher intensities (through inclusion of additional loads) and lower frequencies, potentially creating stronger stimuli and facilitating adequate recovery