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1.
IUCrJ ; 8(Pt 6): 878-895, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34804542

RESUMO

Here, we illustrate what happens inside the catalytic cleft of an enzyme when substrate or ligand binds on single-millisecond timescales. The initial phase of the enzymatic cycle is observed with near-atomic resolution using the most advanced X-ray source currently available: the European XFEL (EuXFEL). The high repetition rate of the EuXFEL combined with our mix-and-inject technology enables the initial phase of ceftriaxone binding to the Mycobacterium tuberculosis ß-lactamase to be followed using time-resolved crystallography in real time. It is shown how a diffusion coefficient in enzyme crystals can be derived directly from the X-ray data, enabling the determination of ligand and enzyme-ligand concentrations at any position in the crystal volume as a function of time. In addition, the structure of the irreversible inhibitor sulbactam bound to the enzyme at a 66 ms time delay after mixing is described. This demonstrates that the EuXFEL can be used as an important tool for biomedically relevant research.

2.
Ultramicroscopy ; : 113409, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34756481

RESUMO

A method for recovering complex structure factors from many simultaneously excited Bragg beam in- tensities is described. The method is applied to simulated transmission electron diffraction data over a wide range of crystal thickness and beam energies. The method is based on iterated projections between structure and scattering matrices, which are related by a matrix unit ary transformation, exponential, which we invert. The algorithm removes multiple-scattering perturbations from diffraction data and might be extended to other fields, including X-ray and neutron diffraction and cryo-electron microscopy. Because coherent multiple scattering involves interference between Bragg beams, the method also solves the phase problem. Unlike dynamical inversion from electron microscope images or ptychography data, the method, which starts with Bragg beam intensities, provides complex structure factors unaffected by focusing errors or resolution limitations imposed by lenses. We provide inversions from simulated data with 441 simultaneously excited Bragg beams over a range of thickness and beam energy. We discuss the retrieval of chirality information from enantiomorphs, the efficient incorporation of symmetry information using the irreducible representation of the group of structure matrices, and the effect of HOLZ lines to provide three-dimensional information.

3.
Arch Public Health ; 79(1): 172, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620222

RESUMO

BACKGROUND: In collaboration with building developers, the Housing for Health team is contributing to the design of community-based congregate living facilities to support healthy living in older adults. There may also be opportunities to improve the surrounding neighbourhoods by collaborating with the municipalities where the developments are located. We will evaluate whether one or more of these comprehensive interventions lead to changes in the perceived, microscale, and macroscale neighbourhood-built environment (BE) and amenities, and impacts on the physical activity (PA), healthy eating, and social connections of residents. In parallel, we will gather qualitative data to provide a more in-depth understanding of how the BE may facilitate or hinder resident's healthy living outcomes. METHODS: This project employs a quasi-experimental pre-post design with at least one or more intervention and control sites. The quantitative BE evaluation will include pre- and post-intervention assessments of neighbourhood macroscale (e.g., layout of communities) and microscale (e.g., street details and characteristics) changes using Geographical Information Systems (GIS) and Microscale Audit Pedestrian Streetscapes (MAPS) audits, respectively. The quantitative resident evaluation will include self-report (i.e., surveys) and objective assessments (i.e., accelerometers, Global Positioning System [GPS]) of residents at baseline (3-6-months pre-move-in) and follow-up (3-6-months and 9-12-months post-move-in if possible). The qualitative resident-environment component will involve in-depth semi-structured interviews post-intervention with building residents, family members, and stakeholders involved in the design/development and/or operation of the intervention site(s). Participant observations will be completed in the building and neighbourhood environments of the intervention site(s). DISCUSSION: Findings will provide evidence on whether and how comprehensive changes to the BE and amenities of at least one congregate living facility and the surrounding neighbourhood can impact PA, healthy eating, and social connections of older adults. Successful intervention elements will be scaled up in future work. We will disseminate findings to a broad audience including the scientific community via peer-reviewed publications, conference presentations, and discussion panels; and the private, public, and not-for-profit sectors via reports, public presentations, and/or communications via our partners and their networks. TRIAL REGISTRATION: Protocol ID: 1819-HQ-000051. ClinicalTrials.gov ID: NCT05031273. Registered 29 June 2021 with ClinicalTrials.gov.

4.
Health Place ; 72: 102676, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34700061

RESUMO

This scoping review summarizes the literature about how ambient (outdoor) air pollution impacts movement behaviours (i.e., physical activity, sedentary behaviour, and sleep), or beliefs about movement behaviours. Of 6552 potential documents, 58 documents and 218 findings were included in the final synthesis. Most studies were from the United States and China, involved cross-sectional designs, and included mixed age groups. Overall, unfavourable changes/associations (i.e., decreased/lower physical activity, increased/higher sedentary-related behaviour, and decreased/lower sleep duration and quality) or no change/association in movement behaviours in relation to ambient air pollution were identified. Our findings suggest that more attention should be given to understanding the impact of ambient air pollution on movement behaviours in general and in diverse countries and vulnerable populations such as children or older adults.

5.
J Nutr Educ Behav ; 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34690078

RESUMO

OBJECTIVE: To develop and evaluate the reliability of a 24-hour movement behavior questionnaire for physical activity, sedentary behavior, and sleep for youth in South Korea. DESIGN: Mixed-methods study using literature review, expert panels, pilot tests, and test-retest reliability. SETTING: Seoul and Gyeongg-do, South Korea. PARTICIPANTS: A convenience sample of middle and high school students for a pilot test (n = 120) and reliability testing (n = 147). MAIN OUTCOME MEASURES: The reliability of a 24-hour movement behavior questionnaire. ANALYSIS: Cohen's kappa, Spearman, and intraclass correlation coefficients for test-retest reliability testing. RESULTS: The questionnaire consisted of 19 questions in 5 categories: general information, sleep and nap, active transportation-related activity, school life, and free-time activities. The 24-hour movement behavior questionnaire achieved moderate reliability for all sleep, physical activity, and sedentary (r = 0.79, 0.61, 0.56). The amount of sleep, physical activity, and sedentary behavior indicated moderate-to-good rest-retest reliability, with intraclass correlation coefficients ranging from 0.54 to 0.79 (P < 0.01). CONCLUSIONS AND IMPLICATIONS: The 24-hour movement behavior questionnaire was reliable for measuring sleep, physical activity, and sedentary behavior in Korean adolescents aged 13-17 years. The development of this questionnaire could facilitate more accurate and useful measurements of adolescent's activities and lifestyles in South Korea.

6.
JMIR Form Res ; 5(10): e29064, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34623317

RESUMO

BACKGROUND: Mind-body interventions have the potential to positively impact the symptom burden associated with primary biliary cholangitis (PBC). Interventions are more likely to be effective if they are informed by a theoretical framework. The Behaviour Change Wheel (BCW) and the behaviour change technique taxonomy version 1 (BCTv1) provide frameworks for intervention development. OBJECTIVE: This study describes how theory has guided the development of a 12-week multicomponent mind-body wellness intervention for PBC. METHODS: The steps involved in developing the BCW intervention included specifying the target behavior; explaining barriers and facilitators using the Capability, Opportunity, Motivation, and Behaviour and the theoretical domains framework; identifying intervention functions to target explanatory domains; and selecting relevant behavior change techniques to address intervention functions. Qualitative data from patients with inflammatory bowel disease using an earlier version of the program and feedback from a PBC patient advisory team were used to guide intervention development. RESULTS: Barriers and facilitators to intervention participation associated with capability, opportunity, and motivation were identified. Intervention functions and behavior change techniques were identified to target each barrier and facilitator. CONCLUSIONS: The Peace Power Pack PBC intervention was developed to help individuals with PBC manage their symptom burden. The theoretical frameworks employed in this intervention provide direction on targeting antecedents of behavior and allow standardized reporting of intervention components. TRIAL REGISTRATION: ClinicalTrials.gov NCT04791527; https://clinicaltrials.gov/ct2/show/NCT04791527.

7.
Appl Physiol Nutr Metab ; 46(10): 1225-1240, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34370965

RESUMO

Daily life has changed for families due to the COVID-19 pandemic. The aim of this repeated cross-sectional study was to describe movement behaviours in Canadian children and youth 6 months into the pandemic (T2; October 2020) compared with the start of the pandemic (T1, April 2020). An online survey was distributed to parents (N = 1568) of children and/or youth (5-17 years; 58% girls) in October 2020. The survey assessed changes in movement behaviours (physical activity and play, sedentary behaviours, and sleep) from before the pandemic to October 2020 (T2). We compared these data with spring data (T1; April 2020; Moore et al. 2020; Int. J. Behav. Nutr. Phys. Act, 17:85) collected using identical methodology (N = 1472; 54% girls). We report correlations between movement behaviours and relevant parental factors and provide word frequency distributions for open-ended responses. During the second wave, 4.5% of children (4.6% girls; 4.3% boys) and 1.9% of youth (1.3% girls, 2.4% boys) met the movement guidelines (3.1% overall). Whereas, during the first wave, 4.8% (2.8% girls, 6.5% boys) of children and 0.6% (0.8% girls, 0.5% boys) of youth were meeting combined guidelines (2.6% overall). Parental support was correlated with their child's movement behaviours (T1 and T2). Our study demonstrates the ongoing challenges for children and youth to engage in healthy movement during the pandemic. Novelty: Our large-scale national study demonstrates that children and youth were not meeting the 24-hour movement guidelines during the second wave of the pandemic. Our findings illustrate the need to protect children and youth from the collateral consequences of the pandemic.


Assuntos
COVID-19/epidemiologia , COVID-19/prevenção & controle , Exercício Físico/fisiologia , SARS-CoV-2 , Adolescente , Canadá/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Humanos
8.
Arch Phys Med Rehabil ; 102(10): 1926-1931, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34252393

RESUMO

OBJECTIVES: To measure stationary behavior in a cohort of older adults after total knee arthroplasty (TKA) and determine the clinical utility of the step-defined sedentary lifestyle index (SLI) as a measure of stationary behavior after TKA. DESIGN: Cross-sectional measurement study. SETTING: Participants were recruited from a community intake clinic for hip and knee surgeries. PARTICIPANTS: Sixty-five older adults 3 months after TKA (N=65). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Stationary behaviors, including stationary time, stationary bouts, breaks from stationary time, and the proportion of participants meeting the SLI, were measured in older adults 3 months post TKA using accelerometry. A 2-way analysis of variance test (α=0.05) was conducted to determine the effects of SLI (<5000 or ≥5000 daily steps) and possible interactions with sex on stationary behavior. RESULTS: Participants spent 80% (13.17±2.3h) of their waking time in stationary time and had an average of 6.06 bouts of stationary time >30 minutes per day. Forty (61.5%) of the participants fell below the SLI of 5000 steps/d. SLI had significant effects on both waking stationary time (P<.001) and number of breaks in stationary time (P<.001), with participants taking <5000 daily steps having longer stationary times and fewer breaks in stationary time. Sex had a significant effect on the number of breaks in stationary time (P=.04), with men (n=23, 35%) reporting more breaks than women (n=42, 65%) (mean difference 13.36; 95% confidence interval, -2.67 to 18.69). No interactions were found between SLI and sex. CONCLUSIONS: Both women and men had high levels of stationary behavior 3 months post TKA. The SLI discriminated waking stationary time and breaks in stationary time and may have clinical utility in measurement of stationary behavior.


Assuntos
Artroplastia do Joelho , Comportamento Sedentário , Caminhada/estatística & dados numéricos , Acelerometria , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
9.
J Med Syst ; 45(7): 72, 2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34091771

RESUMO

There is a rapidly evolving need for e-health to support chronic disease self-management and connect patients with their healthcare teams. Patients with cirrhosis have a high symptom burden, significant comorbidities, and a range of psychological and cognitive issues. Patients with cirrhosis were assessed for their readiness and interest in e-health. Adults attending one of two outpatient cirrhosis clinics in Alberta were recruited. Eligible participants were not required to own or have experience with digital technologies or the Internet. Medical history, socioeconomic status, and attitudes regarding e-health, the Computer Proficiency Questionnaire, and the Mobile Device Proficiency Questionnaire were used to describe participants' knowledge and skills. Of the 117 recruited patients, 68.4% owned a computer and 84.6% owned a mobile device. Patients had mean proficiency scores of 72.8% (SD 25.9%) and 69.3% (SD 26.4%) for these devices, respectively. In multiple regression analyses, significant predictors of device proficiency were age, education, and household income. Most patients (78.7%) were confident they could participate in videoconferencing after training and most (61.5%) were interested in an online personalized health management program. This diverse group of patients with cirrhosis had technology ownership, proficiency, and online behaviours similar to the general population. Moreover, the patients were very receptive to e-health if training was provided. This promising data is timely given the unique demands of COVID-19 and its influence on self-management and healthcare delivery to a vulnerable population.


Assuntos
Alfabetização Digital , Internet , Cirrose Hepática , Tecnologia , Telemedicina , Adulto , Idoso , Alberta , COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Preferência do Paciente
10.
J Phys Act Health ; : 1-7, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34186513

RESUMO

BACKGROUND: Potential income disparities were examined in the (1) awareness and uptake of the Children's Fitness Tax Credit (CFTC), and (2) physical activity (PA) of children from families who did and did not claim the credit in Alberta, Canada in 2012 and 2014. METHODS: Secondary analyses of 3 cross-sectional data sets of grade 5 students (10-11 y) were performed, including Alberta Project Promoting healthy Living for Everyone Schools 2012 (N = 1037), and Raising healthy Eating and Active Living Kids Alberta 2012 (N = 2676), and 2014 (N = 3125). Parents reported whether they claimed the CFTC in the previous year, their education and household income, and their child's gender and PA. Children self-reported their PA from the previous 7 days. In Alberta Project Promoting healthy Living for Everyone Schools, children also wore pedometers. Analyses adjusted for clustering within schools and demographic factors. RESULTS: Higher income families (≥$50,000/y) were more likely to be aware of and to have claimed the CFTC compared with low-income families (<$50,000/y). The CFTC was associated with organized PA with larger associations for higher-income families (odds ratio = 9.03-9.32, Ps < .001) compared with lower-income families (odds ratio = 3.27-4.05, Ps < .01). No associations existed for overall PA or pedometer steps with the CFTC. CONCLUSIONS: Income disparities exist in the awareness, uptake, and potential impact of the CFTC. Tax credits are not effective in promoting overall PA.

11.
N Z Med J ; 134(1534): 51-65, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33927438

RESUMO

AIM: This study compared accelerometer-measured physical activity (PA) patterns in adolescents living in diverse urban and rural areas of Otago, New Zealand. METHOD: Participants (n=377; age: 14.9±1.4 years; 66.8% female; 23 schools) completed an online school travel survey, anthropometry and seven-day PA accelerometer assessment. Participants resided in large (n=237), medium (n=45) and small (n=44) urban areas or rural settings (n=51). RESULTS: Overall, participants participated in 54.4±21.0 minutes of moderate-to-vigorous physical activity (MVPA) daily and 35.0% met PA guidelines (school day vs weekend day: 40.8% vs 26.0%; p<0.001) with no difference across geographical settings. A greater proportion of males (43.2% vs 31.9%; p=0.016), school sport participants (70.1% vs 54.0%; p=0.005) and active-transport-to-school users (40.2% vs 26.1%) met PA guidelines compared to their counterparts. Compared to rural adolescents, those from large urban areas accumulated more MVPA during the school commute time (before school: 8.3±6.7 vs 5.3±3.8 minutes, p<0.001; after school: 10.1±6.0 vs 7.7±4.3 min, p=0.003), but overall spent more time sedentary (584.9±84.7 vs 527.8±88.2 minutes/day; p<0.001). CONCLUSION: PA in Otago adolescents is low, with significant differences by gender, sport participation, mode of travel to school and geographical setting. Increased PA should be encouraged in both urban and rural adolescents.


Assuntos
Exercício Físico/psicologia , Comportamentos Relacionados com a Saúde , População Rural/estatística & dados numéricos , População Urbana/estatística & dados numéricos , Atividades Cotidianas/psicologia , Adolescente , Comportamento do Adolescente/psicologia , Feminino , Humanos , Masculino , Nova Zelândia , Características de Residência , Serviços de Saúde Escolar , Participação Social
12.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33753488

RESUMO

Chloride ion-pumping rhodopsin (ClR) in some marine bacteria utilizes light energy to actively transport Cl- into cells. How the ClR initiates the transport is elusive. Here, we show the dynamics of ion transport observed with time-resolved serial femtosecond (fs) crystallography using the Linac Coherent Light Source. X-ray pulses captured structural changes in ClR upon flash illumination with a 550 nm fs-pumping laser. High-resolution structures for five time points (dark to 100 ps after flashing) reveal complex and coordinated dynamics comprising retinal isomerization, water molecule rearrangement, and conformational changes of various residues. Combining data from time-resolved spectroscopy experiments and molecular dynamics simulations, this study reveals that the chloride ion close to the Schiff base undergoes a dissociation-diffusion process upon light-triggered retinal isomerization.


Assuntos
Canais de Cloreto/metabolismo , Cloretos/metabolismo , Rodopsinas Microbianas/metabolismo , Cátions Monovalentes/metabolismo , Canais de Cloreto/isolamento & purificação , Canais de Cloreto/efeitos da radiação , Canais de Cloreto/ultraestrutura , Cristalografia/métodos , Radiação Eletromagnética , Lasers , Simulação de Dinâmica Molecular , Nocardioides , Conformação Proteica em alfa-Hélice/efeitos da radiação , Estrutura Terciária de Proteína/efeitos da radiação , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/efeitos da radiação , Proteínas Recombinantes/ultraestrutura , Retinaldeído/metabolismo , Retinaldeído/efeitos da radiação , Rodopsinas Microbianas/isolamento & purificação , Rodopsinas Microbianas/efeitos da radiação , Rodopsinas Microbianas/ultraestrutura , Água/metabolismo
13.
Nat Commun ; 12(1): 1762, 2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33741910

RESUMO

Time-resolved studies of biomacromolecular crystals have been limited to systems involving only minute conformational changes within the same lattice. Ligand-induced changes greater than several angstroms, however, are likely to result in solid-solid phase transitions, which require a detailed understanding of the mechanistic interplay between conformational and lattice transitions. Here we report the synchronous behavior of the adenine riboswitch aptamer RNA in crystal during ligand-triggered isothermal phase transitions. Direct visualization using polarized video microscopy and atomic force microscopy shows that the RNA molecules undergo cooperative rearrangements that maintain lattice order, whose cell parameters change distinctly as a function of time. The bulk lattice order throughout the transition is further supported by time-resolved diffraction data from crystals using an X-ray free electron laser. The synchronous molecular rearrangements in crystal provide the physical basis for studying large conformational changes using time-resolved crystallography and micro/nanocrystals.


Assuntos
Conformação de Ácido Nucleico , Transição de Fase , RNA/química , Riboswitch , Adenina/química , Aptâmeros de Nucleotídeos/química , Cristalografia por Raios X , Microscopia de Força Atômica/métodos , Microscopia de Polarização/métodos , Modelos Moleculares , Imagem com Lapso de Tempo/métodos
14.
Ultramicroscopy ; 222: 113214, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33561601

RESUMO

A method for recovering complex structure factors from many simultaneously excited Bragg beam in- tensities is described. The method is applied to simulated transmission electron diffraction data over a wide range of crystal thickness and beam energies. The method is based on iterated projections between structure and scattering matrices, which are related by a matrix unit ary transformation, exponential, which we invert. The algorithm removes multiple-scattering perturbations from diffraction data and might be extended to other fields, including X-ray and neutron diffraction and cryo-electron microscopy. Because coherent multiple scattering involves interference between Bragg beams, the method also solves the phase problem. Unlike dynamical inversion from electron microscope images or ptychography data, the method, which starts with Bragg beam intensities, provides complex structure factors unaffected by focusing errors or resolution limitations imposed by lenses. We provide inversions from simulated data with 441 simultaneously excited Bragg beams over a range of thickness and beam energy. We discuss the retrieval of chirality information from enantiomorphs, the efficient incorporation of symmetry information using the irreducible representation of the group of structure matrices, and the effect of HOLZ lines to provide three-dimensional information.

15.
Sleep Med ; 78: 141-148, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33429290

RESUMO

OBJECTIVE: To create a sleep duration classification technique for waist-worn ActiGraph accelerometers in preschool-aged children. METHODS: Children wore ActiGraph wGT3X-BT accelerometers on their right hip for 7 days (24 h/day). Ground truth nap, sleep, and wake were estimated through visual inspection of accelerometer data, guided by sleep log-sheets and previously published visual inspection heuristics. Raw accelerometer data (30Hz) were used to generate 144 features aggregated to 1-min epochs. Machine learning classification (ie, Random Forest and Hidden Markov Modeling [HMM]) predicted nap, sleep, and wake. A simplified prediction formula was also created using features (n = 10) with the highest mean decrease in Gini index during training of Random Forests, and temporally smoothed with rolling median calculations. RESULTS: Children (n = 89, mean age = 4.5 years, 67% boys) contributed >600,000 min of accelerometer data. Overall classification accuracy of the Random Forest and HMM classifier was 96.2% (95%CI: 96.1, 96.2%), with a Kappa score of 0.93. Additionally, overall classification accuracy for the temporally smoothed simplified formula was 93.7% (95%CI: 93.6, 93.7%) with Kappa = 0.87. Nap prediction accuracy was 99.8% for the final machine learning model, and 86.1% for the simplified formula. For participant-level daily summaries, generally small but statistically significant differences were found between machine learning and ground truth behaviour predictions, whereas non-significant differences were found between the simplified formulas and ground truth predictions. CONCLUSIONS: Predictions for both machine learning and the simplified formula had almost perfect agreement with visual inspection ground truth measurements. Future research is needed to confirm these findings using polysomnography ground truth sleep measurements.


Assuntos
Acelerometria , Transtornos Mentais , Criança , Pré-Escolar , Feminino , Humanos , Aprendizado de Máquina , Masculino , Polissonografia , Sono
17.
J Cardiopulm Rehabil Prev ; 41(4): 337-342, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32947325

RESUMO

PURPOSE: Sedentary time (ST) and lack of physical activity increase the risk of adverse outcomes for those living with coronary artery disease (CAD). Little is known about how much ST, light physical activity (LPA), and moderate to vigorous physical activity (MVPA) that CAD participants not attending cardiac rehabilitation engage in, the locations where they engage in these behaviors, and how far from home the locations are. METHODS: Participants completed a survey and wore an accelerometer and global positioning system receiver for 7 d at baseline and 6 mo later. RESULTS: Accelerometer analyses (n = 318) showed that participants averaged 468.4 ± 102.7 of ST, 316.1 ± 86.5 of LPA, and 32.9 ± 28.9 of MVPA min/d at baseline. ST and LPA remained stable at 6 mo, whereas MVPA significantly declined. The global positioning system (GPS) analyses (n = 315) showed that most of participant ST, LPA, and MVPA time was spent at home followed by other residential, retail/hospitality, and work locations at baseline and 6 mo. When not at home, the average distance to a given location ranged from approximately 9 to 18 km. CONCLUSIONS: Participants with CAD spent the majority of their time being sedentary. Home was the location used the most to engage in ST, LPA, and MVPA. When not home, ST, LPA, and MVPA were distributed across a variety of locations. The average distance from home to a given location suggests that proximity to home may not be a barrier from an intervention perspective.

18.
Br J Health Psychol ; 26(2): 588-605, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33336562

RESUMO

Objectives This study examined the impact of the COVID-19 lockdown on the physical activity (PA) of UK adults and potential motivational determinants of such behaviour. Design and methods A survey was conducted with 1,521 UK adults recruited through Prolific.co in early June 2020. Along with demographic information, questions assessed current PA, changes in PA modalities (i.e., overall, around the home, for transport, in the workplace, in the local neighbourhood, at recreation/sport facilities) related to the lockdown, and beliefs about capabilities, opportunities, and motivations according to the COM-B model. A series of logistic regressions were constructed to examine associations between shifts in the PA modalities and the COM-B components. Results The majority of respondents (57%) had either maintained or increased their levels of PA during the COVID-19 lockdown. However, the proportion meeting PA guidelines (31%) was low and engagement in sedentary-related behaviour for both work and leisure increased substantially during the lockdown. The components of the COM-B model were associated with shifts in PA. In particular, physical opportunity (odds ratios ranging from 1.14 to 1.20) and reflective motivation (odds ratios ranging from 1.11 to 1.25) appeared to be the most consistent predictors of behaviour. Conclusions If UK adults believed they had the physical opportunity and were motivated, they were more likely to have maintained or increased their PA during the COVID-19 lockdown. However, the majority of adults are not meeting the UK guidelines on PA and the prevalence of PA is substantially lower than national surveys prior to the pandemic. Statement of contribution What is already known on this subject? The COVID-19 pandemic has significantly disrupted the daily routines of citizens globally. Engagement in physical activity appears to have declined as a result of the requirement to self-isolate and stay in place. The COM-B model of behaviour change is a useful framework for identifying the correlates and determinants of behaviour. What does this study add? Though most UK adults maintained or increased their engagement in physical activity during the COVID-19 pandemic, the majority did not meet recommended guidelines. Reflective processes and physical opportunity were the primary predictors of change in physical activity.


Assuntos
COVID-19 , Pandemias , Adulto , Controle de Doenças Transmissíveis , Exercício Físico , Humanos , SARS-CoV-2 , Reino Unido
19.
PLoS One ; 15(12): e0242999, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33270692

RESUMO

BACKGROUND: Accumulating evidence suggests that the built environment is associated with physical activity. The extent to which the built environment may support adherence to physical activity interventions is unclear. The aim of this study was to investigate whether the neighbourhood built environment constrains or facilitates adherence and steps taken during a 12-week internet-delivered pedometer-based physical activity intervention (UWALK). METHOD: The study was undertaken in Calgary (Canada) between May 2016 and August 2017. Inactive adults (n = 573) completed a telephone survey measuring sociodemographic characteristics and perceived neighbourhood walkability. Following the survey, participants were mailed a pedometer and instructions for joining UWALK. Participants were asked to report their daily pedometer steps into the online program on a weekly basis for 12 weeks (84 days). Walk Score® estimated objective neighbourhood walkability and the Neighbourhood Environment Walkability Scale-Abbreviated (NEWS-A) measured participants self-reported neighbourhood walkability. Regression models estimated covariate-adjusted associations of objective and self-reported walkability with: 1) adherence to the UWALK intervention (count of days with steps reported and count of days with 10000 steps reported), and; 2) average daily pedometer steps. RESULTS: On average, participants undertook 8565 (SD = 3030) steps per day, reported steps on 67 (SD = 22.3) of the 84 days, and achieved ≥10000 steps on 22 (SD = 20.5) of the 84 days. Adjusting for covariates, a one-unit increase in self-reported walkability was associated on average with 45.76 (95CI 14.91, 76.61) more daily pedometer steps. Walk Score® was not significantly associated with steps. Neither objective nor self-reported walkability were significantly associated with the UWALK adherence outcomes. CONCLUSION: The neighbourhood built environment may support pedometer-measured physical activity but may not influence adherence to pedometer interventions. Perceived walkability may be more important than objectively-measured walkability in supporting physical activity during pedometer interventions.


Assuntos
Acelerometria/instrumentação , Características de Residência , Caminhada/psicologia , Alberta , Terapia Comportamental/métodos , Ambiente Construído , Exercício Físico/psicologia , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Comportamento Sedentário , Autorrelato , Fatores Socioeconômicos , Inquéritos e Questionários
20.
J Aging Phys Act ; : 1-8, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-33378742

RESUMO

Few validated tools exist for measuring physical activity following total knee arthroplasty (TKA) despite the importance of returning to sufficient levels of physical activity post-TKA to achieve health benefits. This study examined the validity of two clinical measures-the Fitbit, a commercially available personal activity monitor, and the Community Healthy Activities Model Program for Seniors (CHAMPS), a self-report questionnaire-compared with a reference standard accelerometer, the SenseWearTM Armband (SWA). At 6-month post-TKA, 47 participants wore the Fitbit and SWA for 4 days and then completed the CHAMPS. Moderate-to-good correlation was observed between the Fitbit and SWA for steps (intraclass correlation coefficient [ICC] = .79), energy expenditure (ICC = .78), and energy expenditure <3 METS (ICC = .79). Poor-to-moderate correlation was observed between the CHAMPS and SWA (ICC = .43) with the questionnaire reporting lower daily energy expenditures than the SWA. Results showed that Fitbit may be a reasonable measurement tool to measure steps and energy expenditures in older adults following TKA.

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