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1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4063-4066, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018891

RESUMO

The ballistocardiography is a technique that measures the heart rate from the mechanical vibrations of the body due to the heart movement. In this work a novel noninvasive device placed under the mattress of a bed estimates the heart rate using the ballistocardiography. Different algorithms for heart rate estimation have been developed.


Assuntos
Balistocardiografia , Leitos , Acelerometria , Frequência Cardíaca , Movimento
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 653-656, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018072

RESUMO

This work demonstrates the effectiveness of Convolutional Neural Networks in the task of pose estimation from Electromyographical (EMG) data. The Ninapro DB5 dataset was used to train the model to predict the hand pose from EMG data. The models predict the hand pose with an error rate of 4.6% for the EMG model, and 3.6% when accelerometry data is included. This shows that hand pose can be effectively estimated from EMG data, which can be enhanced with accelerometry data.


Assuntos
Mãos , Redes Neurais de Computação , Acelerometria , Eletromiografia , Humanos
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4487-4490, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018991

RESUMO

Wearable sensors have been investigated for the purpose of gait analysis, namely gait event detection. Many types of algorithms have been developed specifically using inertial sensor data for detecting gait events. Though much attention has turned toward machine learning algorithms, most of these approaches suffer from large computational requirements and are not yet suitable for real-time applications such as in prostheses or for feedback control. Current rules-based algorithms for real-time use often require fusion of multiple sensor signals to achieve high accuracy, thus increasing complexity and decreasing usability of the instrument. We present our results of a novel, rules-based algorithm using a single accelerometer signal from the foot to reliably detect heel-strike and toe-off events. Using the derivative of the raw accelerometer signal and applying an optimizer and windowing approach, high performance was achieved with a sensitivity and specificity of 94.32% and 94.70% respectively, and a timing error of 6.52 ± 22.37 ms, including trials involving multiple speed transitions. This would enable development of a compact wearable system for robust gait analysis in real-world settings, providing key insights into gait quality with the capability for real-time system control.


Assuntos
Algoritmos , Marcha , Acelerometria , Fenômenos Biomecânicos ,
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4592-4595, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019016

RESUMO

Gait analysis has many potential applications in understanding the activity profiles of individuals in their daily lives, particularly when studying the progression of recovery following injury, or motor deterioration in pathological conditions. One of the many challenges of conducting such analyses in the home environment is the correct and automatic identification of bouts of gait activity. To address this, a novel method for determining bouts of gait from accelerometer data recorded from the shank is presented. This method is fully automated and includes an adaptive thresholding approach which avoids the necessity for identifying subject-specific thresholds. The algorithm was tested on data recorded from 15 healthy subjects during self-selected slow, normal and fast walking speeds ranging from 0.48 ± 0.19 to 1.38 ± 0.33m/s and a single subject with PD walking at their normal walking speed (1.41 ± 0.08m/s) using accelerometers on the shanks. Intra-Class Correlation (ICC) confirmed high levels of agreement between bout onset/offset times and durations estimated using the algorithm, experimentally recorded stopwatch times and manual annotation for the healthy subjects (r=0.975, p <; 0.001; r=0.984, p<; 0.001) and moderate agreement for the PD subject (r=0.663, p<; 0.001). Mean absolute errors between accelerometer-derived and manually-annotated times were calculated, and ranged from 0.91 ± 0.05 s to 1.17 ± 2.26 s for bout onset detection, 0.80 ± 0.23 s to 2.41 ± 3.77 s for offset detection and 1.27 ± 0.13 s to 3.67 ± 4.59 s for bout durations.


Assuntos
Marcha , Caminhada , Acelerometria , Algoritmos , Humanos , Velocidade de Caminhada
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4604-4607, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019019

RESUMO

Wearable devices offer a possible solution for acquiring objective measurements of physical activity. Most current algorithms are derived using data from healthy volunteers. It is unclear whether such algorithms are suitable in specific clinical scenarios, such as when an individual has altered gait. We hypothesized that algorithms trained on healthy population will result in less accurate results when tested in individuals with altered gait. We further hypothesized that algorithms trained on simulated-pathological gait would prove better at classifying abnormal activity. We studied healthy volunteers to assess whether activity classification accuracy differed for those with healthy and simulated-pathological conditions. Healthy participants (n=30) were recruited from the University of Leeds to perform nine predefined activities under healthy and simulated-pathological conditions. Activities were captured using a wrist-worn MOX accelerometer (Maastricht Instruments, NL). Data were analyzed based on the Activity-Recognition-Chain process. We trained a Neural-Network, Random-Forests, k-Nearest-Neighbors (k-NN), Support-Vector-Machines (SVM) and Naive Bayes models to classify activity. Algorithms were trained four times; once with `healthy' data, and once with `simulated-pathological data' for each of activity-type and activity-task classification. In activity-type instances, the SVM provided the best results; the accuracy was 98.4% when the algorithm was trained and then tested with unseen data from the same group of healthy individuals. Accuracy dropped to 52.8% when tested on simulated-pathological data. When the model was retrained with simulated-pathological data, prediction accuracy for the corresponding test set was 96.7%. Algorithms developed on healthy data are less accurate for pathological conditions. When evaluating pathological conditions, classifier algorithms developed using data from a target sub-population can restore accuracy to above 95%.


Assuntos
Exercício Físico , Articulação do Punho , Acelerometria , Teorema de Bayes , Voluntários Saudáveis , Humanos
6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4636-4639, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019027

RESUMO

Breathing rate was estimated from chest-worn accelerometry collected from 1,522 servicemembers during training by a wearable physiological monitor. A total of 29,189 hours of training and sleep data were analyzed. The primary purpose of the monitor was to assess thermal-work strain and avoid heat injuries. The monitor design was thus not optimized to estimate breathing rate. Since breathing rate cannot be accurately estimated during periods of high activity, a qualifier was applied to identify sedentary time periods, totaling 8,867 hours. Breathing rate was estimated for a total of 4,179 hours, or 14% of the total collection and 47% of the sedentary total, primarily during periods of sleep. The breathing rate estimation method was compared to an FDA 510(K)-cleared criterion breathing rate sensor (Zephyr, Annapolis MD, USA) in a controlled laboratory experiment, which showed good agreement between the two techniques. Contributions of this paper are to: 1) provide the first analysis of accelerometry-derived breathing rate on free-living data including periods of high activity as well as sleep, along with a qualifier that effectively identifies sedentary periods appropriate for estimating breathing rate; 2) test breathing rate estimation on a data set with a total duration that is more than 60 times longer than that of the largest previously reported study, 3) test breathing rate estimation on data from a physiological monitor that has not been expressly designed for that purpose.


Assuntos
Acelerometria , Taxa Respiratória , Monitorização Fisiológica , Sono , Tórax
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4668-4671, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33019035

RESUMO

Wearable inertial sensors offer the possibility to monitor sleeping position and respiration rate during sleep, enabling a comfortable and low-cost method to remotely monitor patients. Novel methods to estimate respiration rate and position during sleep using accelerometer data are presented, with algorithm performance examined for two sensor locations, and accelerometer-derived respiration rate compared across sleeping positions. Eleven participants (9 male; aged: 47.82±14.14 years; BMI 30.9±5.27 kg/m2; AHI 5.77±4.18) undergoing a scheduled clinical polysomnography (PSG) wore a tri-axial accelerometer on their chest and upper abdomen. PSG cannula flow and position data were used as benchmark data for respiration rate (breaths per minute, bpm) and position. Sleeping position was classified using logistic regression, with features derived from filtered acceleration and orientation. Accelerometer-derived respiration rate was estimated for 30 s epochs using an adaptive peak detection algorithm which combined filtered acceleration and orientation data to identify individual breaths. Sensor-derived and PSG respiration rates were then compared. Mean absolute error (MAE) in respiration rate did not vary between sensor locations (abdomen: 1.67±0.37 bpm; chest: 1.89±0.53 bpm; p=0.52), while reduced MAE was observed when participants lay on their side (1.58±0.54 bpm) compared to supine (2.43±0.95 bpm), p<0.01. MAE was less than 2 bpm for 83.6% of all 30 s windows across all subjects. The position classifier distinguished supine and left/right with a ROC AUC of 0.87, and between left and right with a ROC AUC of 0.94. The proposed methods may enable a low-cost solution for in-home, long term sleeping posture and respiration monitoring.


Assuntos
Taxa Respiratória , Dispositivos Eletrônicos Vestíveis , Acelerometria , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Polissonografia , Sono
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 588-591, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018057

RESUMO

Stroke survivors are often characterized by hemiparesis, i.e., paralysis in one half of the body, that severely affects upper limb movements. Continuous monitoring of the progression of hemiparesis requires manual observation of the limb movements at regular intervals and hence is a labour intensive process. In this work, we use wrist-worn accelerometers for automated assessment of hemiparetic severity in acute stroke patients through bivariate Poincaré analysis between accelerometer data from the two hands during spontaneous and instructed movements. Experiments show that while the bivariate Poincaré descriptors CSD1 and CSD2 can identify hemiparetic patients from control subjects, a novel descriptor called Complex Cross-Correlation Measure (C3M) can distinguish between moderate and severe hemiparesis. Further, we justify the use of C3M by showing that it is described by multiple-lag cross-correlations, representing the co-ordination of activity between two hands. The descriptors are compared against the National Institutes of Health Stroke Scale (NIHSS), the clinical gold standard for evaluation of hemiparetic severity, and studied using statistical tests for developing supervised models for hemiparesis classification.Clinical relevance-This study establishes the suitability of wrist-worn accelerometers in identifying hemiparetic severity in stroke patients through novel descriptors of hand co-ordination.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Dispositivos Eletrônicos Vestíveis , Acelerometria , Humanos , Paresia/diagnóstico , Acidente Vascular Cerebral/complicações , Estados Unidos
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 812-815, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018109

RESUMO

The incidence of fall-related injuries in older adults is high. Given the significant and adverse outcomes that arise from injurious falls in older adults, it is of the utmost importance to identify older adults at greater risk for falls as early as possible. Given that balance dysfunction provides a significant risk factor for falls, an automated and objective identification of balance dysfunction in community dwelling older adults using wearable sensor data when walking may be beneficial. In this study, we examine the feasibility of using wearable sensors, when walking, to identify older adults who have trouble with balance at an early stage using state-of-the-art machine learning techniques. We recruited 21 community dwelling older women. The experimental paradigm consisted of two tasks: Normal walking with a self-selected comfortable speed on an instrumented treadmill and a test of reflexive postural response, using the motor control test (MCT). Based on the MCT, identification of older women with low or high balance function was performed. Using short duration accelerometer data from sensors placed on the knee and hip while walking, supervised machine learning was carried out to classify subjects with low and high balance function. Using a Gradient Boosting Machine (GBM) algorithm, we classified balance function in older adults using 60 seconds of accelerometer data with an average cross validation accuracy of 91.5% and area under the receiver operating characteristic curve (AUC) of 0.97. Early diagnosis of balance dysfunction in community dwelling older adults through the use of user friendly and inexpensive wearable sensors may help in reducing future fall risk in older adults through earlier interventions and treatments, and thereby significantly reduce associated healthcare costs.


Assuntos
Vida Independente , Equilíbrio Postural , Acelerometria , Acidentes por Quedas/prevenção & controle , Idoso , Feminino , Humanos , Aprendizado de Máquina
10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 847-850, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018117

RESUMO

Parkinson's disease (PD) patients with freezing of gait (FOG) can suddenly lose their forward moving ability leading to unexpected falls. To overcome FOG and avoid the falls, a real-time accurate FOG detection or prediction system is desirable to trigger on-demand cues. In this study, we designed and implemented an in-place movement experiment for PD patients to provoke FOG and meanwhile acquired multimodal physiological signals, such as electroencephalography (EEG) and accelerometer signals. A multimodal model using brain activity from EEG and motion data from accelerometers was developed to improve FOG detection performance. In the detection of over 700 FOG episodes observed in the experiments, the multimodal model achieved 0.211 measured by Matthews Correlation Coefficient (MCC) compared with the single-modal models (0.127 or 0.139).Clinical Relevance- This is the first study to use multimodal: EEG and accelerometer signal analysis in FOG detection, and an improvement was achieved.


Assuntos
Transtornos Neurológicos da Marcha , Doença de Parkinson , Acelerometria , Eletroencefalografia , Marcha , Transtornos Neurológicos da Marcha/diagnóstico , Humanos , Doença de Parkinson/diagnóstico
11.
Crit Care Resusc ; 22(3): 245-252, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32900331

RESUMO

OBJECTIVE: The degree of sedation or agitation in critically ill patients is typically assessed with the Richmond Agitation and Sedation Scale (RASS). However, this approach is intermittent and subject to unrecognised variation between assessments. High frequency accelerometry may assist in achieving a quantitative and continuous assessment of sedation while heralding imminent agitation. DESIGN: We undertook a prospective, observational pilot study. SETTING: An adult tertiary intensive care unit in Melbourne, Australia. PARTICIPANTS: 20 patients with an admission diagnosis of trauma. MAIN OUTCOME MEASURES: Accelerometers were applied to patients' wrists and used to continuously record patient movement. Video data of patient behaviour were simultaneously collected, and observers blinded to accelerometry data were adjudicated the RASS score every 30 seconds. Exploratory analyses were undertaken. RESULTS: Patients were enrolled for a median duration of 9.7 hours (interquartile range [IQR], 0-22.8) and a total of 160 hours. These patients had a median RASS score of 0 (IQR, -4 to 0). A 2-minute moving window of amplitude variance was seen to reflect contemporaneous fluctuations in motor activity and was proportional to the RASS score. Furthermore, the moving window of amplitude variance was observed to spike immediately before ≥ 2 point increases in the RASS score. CONCLUSIONS: We describe a novel approach to the analysis of wrist accelerometry data in critically ill patients. This technique not only appears to provide novel and continuous information about the depth of sedation or degree of agitation, it is also notable in its aptitude to anticipate impending transitions to higher RASS values.


Assuntos
Acelerometria/estatística & dados numéricos , Estado de Consciência , Estado Terminal , Agitação Psicomotora , Adulto , Austrália , Cuidados Críticos , Humanos , Projetos Piloto , Estudos Prospectivos
12.
PLoS One ; 15(8): e0236643, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841239

RESUMO

Accelerometry is a recent method used to quantify workload in team sports. A rapidly increasing number of studies supports the practical implementation of accelerometry monitoring to regulate and optimize training schemes. Therefore, the purposes of this study were: (1) to reflect the current state of knowledge about accelerometry as a method of workload monitoring in invasion team sports according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, and (2) to conclude recommendations for application and scientific investigations. The Web of Science, PubMed and Scopus databases were searched for relevant published studies according to the following keywords: "accelerometry" or "accelerometer" or "microtechnology" or "inertial devices", and "load" or "workload", and "sport". Of the 1383 studies initially identified, 118 were selected for a full review. The main results indicate that the most frequent findings were (i) devices' body location: scapulae; (b) devices brand: Catapult Sports; (iii) variables: PlayerLoadTM and its variations; (iv) sports: rugby, Australian football, soccer and basketball; (v) sex: male; (vi) competition level: professional and elite; and (vii) context: separate training or competition. A great number of variables and devices from various companies make the comparability between findings difficult; unification is required. Although the most common location is at scapulae because of its optimal signal reception for time-motion analysis, new methods for multi-location skills and locomotion assessment without losing tracking accuracy should be developed.


Assuntos
Acelerometria , Desempenho Atlético , Basquetebol , Futebol Americano , Futebol , Carga de Trabalho , Feminino , Sistemas de Informação Geográfica , Humanos , Masculino , Microtecnologia
13.
Am J Occup Ther ; 74(5): 7405205100p1-7405205100p9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32804628

RESUMO

IMPORTANCE: Constraint-induced movement therapy (CIMT) is a common treatment for children with unilateral cerebral palsy (CP). Although clinic-based assessments have demonstrated improvements in arm function after CIMT, whether these changes are translated and sustained outside of a clinic setting remains unclear. OBJECTIVE: Accelerometers were used to quantify arm movement for children with CP 1 wk before, during, and 4 wk or more after CIMT; measurements were compared with those from typically developing (TD) peers. DESIGN: Observational. SETTING: Tertiary hospital and community. PARTICIPANTS: Seven children with CP (5 boys, 2 girls; average [AVE] age ± standard deviation [SD] = 7.4 ± 1.2 yr) and 7 TD peers (2 boys, 5 girls; AVE age ± SD = 7.0 ± 2.3 yr). INTERVENTION: 30-hr CIMT protocol. OUTCOMES AND MEASURES: Use ratio, magnitude ratio, and bilateral magnitude were calculated from the accelerometer data. Clinical measures were administered before and after CIMT, and parent surveys assessed parent and child perceptions of wearing accelerometers. RESULTS: During CIMT, the frequency and magnitude of paretic arm use among children with CP increased in the clinic and in daily life. After CIMT, although clinical scores showed sustained improvement, the children's accelerometry data reverted to baseline values. Children and parents in both cohorts had positive perceptions of accelerometer use. CONCLUSIONS AND RELEVANCE: The lack of sustained improvement in accelerometry metrics after CIMT suggests that therapy gains did not translate to increased movement outside the clinic. Additional therapy may be needed to help transfer gains outside the clinic. WHAT THIS ARTICLE ADDS: Accelerometer measurements were effective at monitoring arm movement outside of the clinic during CIMT and suggested that additional interventions may be needed after CIMT to sustain benefits.


Assuntos
Paralisia Cerebral , Acelerometria , Braço , Criança , Feminino , Humanos , Masculino , Movimento , Modalidades de Fisioterapia , Resultado do Tratamento
14.
PLoS One ; 15(8): e0236573, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32756595

RESUMO

BACKGROUND: South Asians are one of the fastest growing ethnic groups in western countries with a high incidence of chronic diseases like metabolic syndrome and cardiovascular disease occurring at younger ages and lower body weight compared with white Europeans. Physically active lifestyle and reduced sedentary time are modifiable risk factors that can decrease burden of chronic diseases. Population-level surveys based on self-report show South Asians engage in low levels of physical activity. Because of known limitations with self-report data, we aimed to synthesize available evidence to generate a physical activity /sedentary time profile of South Asians from studies using accelerometry. METHODS: We systematically searched Medline, EMBASE, CINAHL, PsycINFO, and SportDiscus. We included studies applying accelerometry to measure physical activity /sedentary time under free-living. Studies with an exclusive focus on drugs or including participants with health conditions/physical disability, and special populations (athletes/pregnant women) were excluded. Two authors independently adjudicated inclusion of citations at title/abstract and full text. We applied a standardized data abstraction form to extract relevant data. We evaluated methodological quality using Newcastle Ottawa Quality Assessment Scale. Due to variability and inconsistencies in measurement and reporting of physical activity /sedentary time, we only provide a narrative synthesis. FINDINGS: We identified only 14 studies(n = 1,338). Despite using similar accelerometry assumptions, we noted variability in reported outcomes for physical activity and sedentary time. Sedentary time ranged from 482(98) to 587 min/day. Mean light physical activity ranged from 211.69(67. 38) to 574(227) min/day. Moderate to vigorous physical activity among South Asian women ranged from 17-41 min/day and among men, 32-43 min/day. CONCLUSION: South Asians exhibited higher levels of physical activity when compared to the Canadian population level survey but not when compared to the American population level survey. Overall, fewer studies, and small sample sizes led to considerable variability limiting any effective comparisons. Results highlight the importance of conducting methodologically robust studies based on random sampling to advance the field, and to capture true levels of sedentary time and physical activity in the South Asian population.


Assuntos
Acelerometria/métodos , Doença Crônica/prevenção & controle , Exercício Físico/fisiologia , Comportamento Sedentário , Adulto , Grupo com Ancestrais do Continente Asiático , Atletas , Canadá/epidemiologia , Doença Crônica/epidemiologia , Grupo com Ancestrais do Continente Europeu , Feminino , Humanos , Estilo de Vida , Masculino , Gravidez , Fatores de Risco , Autorrelato
15.
PLoS One ; 15(8): e0237784, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32813745

RESUMO

Built environments have been cited as important facilitators of activity and research using geographic information systems (GIS) has emerged as a novel approach in exploring environmental determinants. The Active Children Through Individual Vouchers Evaluation Project used GIS to conduct a cross-sectional analysis of how teenager's (aged 13-14) environments impacted on their amount of activity and influences fitness. The ACTIVE Project recruited 270 participants aged 13-14 (year 9) from 7 secondary schools in south Wales, UK. Demographic data and objective measures of accelerometery and fitness were collected from each participant between September and December 2016. Objective data was mapped in a GIS alongside datasets relating to activity provision, active travel routes, public transport stops, main roads and natural resources. This study shows that fitness and physical activity are not correlated. Teenagers who had higher levels of activity also had higher levels of sedentary time/inactivity. Teenagers showed higher amounts of moderate-to-vigorous physical activity if their homes were closer to public transport. However, they were also more active if their schools were further away from public transport and natural resources. Teenagers were fitter if schools were closer to natural resources. Sedentary behaviour, fitness and activity do not cluster in the same teenagers. Policymakers/planning committees need to consider this when designing teenage friendly environments. Access to public transport, active travel, green space and activities that teenagers want, and need could make a significant difference to teenage health.


Assuntos
Saúde do Adolescente/estatística & dados numéricos , Ambiente Construído , Exercício Físico/fisiologia , Aptidão Física/fisiologia , Acelerometria/métodos , Acelerometria/estatística & dados numéricos , Adolescente , Estudos Transversais , Conjuntos de Dados como Assunto , Feminino , Sistemas de Informação Geográfica/estatística & dados numéricos , Humanos , Masculino , Transportes/estatística & dados numéricos , País de Gales
16.
PLoS One ; 15(8): e0236676, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32750073

RESUMO

BACKGROUND: Consumer-based activity trackers are used to measure and improve physical activity. However, the accuracy of these devices as clinical endpoint or coaching tool is unclear. We investigated the use of two activity trackers as measuring and coaching tool in patients with Chronic Obstructive Pulmonary Disease (COPD) and healthy age-matched controls. METHODS: Daily steps were measured by two consumer-based activity trackers (Fitbit Zip, worn at the hip and Fitbit Alta, worn at the wrist) and a validated activity monitor (Dynaport Movemonitor) in 28 patients with COPD and 14 healthy age-matched controls for 14 consecutive days. To investigate the accuracy of the activity trackers as a clinical endpoint, mean step count per patient were compared with the reference activity monitor and agreement was investigated by Bland-Altman plots. To evaluate the accuracy of activity trackers as coaching tool, day-by-day differences within patients were calculated for all three devices. Additionally, consistency of ranking daily steps between the activity trackers and accelerometer was investigated by Kendall correlation coefficient. RESULTS: As a measuring tool, the hip worn activity tracker significantly underestimates daily step count in patients with COPD as compared to DAM (mean±SD Δ-1112±872 steps/day; p<0.0001). This underestimation is less prominent in healthy subjects (p = 0.21). The wrist worn activity tracker showed a non-significant overestimation of step count (p = 0.13) in patients with COPD, and a significant overestimation of daily steps in healthy controls (mean±SD Δ+1907±2147 steps/day; p = 0.006). As a coaching tool, both hip and wrist worn activity tracker were able to pick up the day-by-day variability as measured by Dynaport (consistency of ranking resp. r = 0.80; r = 0.68 in COPD). CONCLUSION: Although the accuracy of hip worn consumer-based activity trackers in patients with COPD and wrist worn activity trackers in healthy subjects as clinical endpoints is unsatisfactory, these devices are valid to use as a coaching tool.


Assuntos
Acelerometria/instrumentação , Coleta de Dados/instrumentação , Monitores de Aptidão Física , Monitorização Ambulatorial/instrumentação , Doença Pulmonar Obstrutiva Crônica , Idoso , Estudos de Casos e Controles , Exercício Físico , Feminino , Humanos , Masculino , Tutoria , Pessoa de Meia-Idade
17.
Am Heart J ; 228: 47-56, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32798787

RESUMO

AIMS: To investigate the effect of the sodium-glucose co-transporter-2 inhibitor empagliflozin on N-terminal pro-b-type natriuretic peptide (NT-proBNP) in patients with heart failure (HF) and reduced ejection fraction (HFrEF). METHODS AND RESULTS: Empire HF was an investigator-initiated, multi-center, double-blinded, placebo-controlled, randomized trial. Patients with mildly symptomatic HFrEF, mean (standard deviation (SD)) age 64 (11) years, 85% male, and mean left ventricular ejection fraction 29% (8), on recommended HF therapy were assigned to receive either empagliflozin 10 mg once daily or placebo for 12 weeks. The primary endpoint was the between-group difference in the change of NT-proBNP from baseline to 12 weeks. In total, 95 patients were assigned to empagliflozin and 95 to placebo. No significant difference in the change of NT-proBNP with empagliflozin versus placebo was observed [Empagliflozin: baseline, median (interquartile range (IQR)) 582 (304-1020) pg/mL, 12 weeks, 478 (281-961) pg/mL; Placebo: baseline, 605 (322-1070) pg/mL, 12 weeks, 520 (267-1075) pg/mL, adjusted ratio of change empagliflozin/placebo 0.98; 95% confidence interval (CI) 0.82-1.11, P = 0.7]. Further, no significant difference was observed in accelerometer-measured daily activity level [adjusted mean difference of change, empagliflozin versus placebo, -26.0 accelerometer counts; 95% CI -88.0 to 36.0, P = 0.4] or Kansas City Cardiomyopathy Questionnaire Overall Summary Score [adjusted mean difference of change, empagliflozin versus placebo 0.8; 95% CI -2.3 to 3.9, P = 0.6]. CONCLUSION: In low-risk patients with HFrEF with mild symptoms and on recommended HF therapy, empagliflozin did not change NT-proBNP after 12 weeks. Further, no change in daily activity level or health status was observed.


Assuntos
Acelerometria/métodos , Atividades Cotidianas , Compostos Benzidrílicos , Glucosídeos , Insuficiência Cardíaca , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Disfunção Ventricular Esquerda/diagnóstico , Compostos Benzidrílicos/administração & dosagem , Compostos Benzidrílicos/efeitos adversos , Método Duplo-Cego , Feminino , Glucosídeos/administração & dosagem , Glucosídeos/efeitos adversos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Inibidores do Transportador 2 de Sódio-Glicose/administração & dosagem , Volume Sistólico
18.
PLoS One ; 15(8): e0221668, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32776927

RESUMO

BACKGROUND: Animal models of brain recovery identify the first days after lesioning as a time of great flux in sensorimotor function and physiology. After rodent motor system lesioning, daily skill training in the less affected forelimb reduces skill acquisition in the more affected forelimb. We asked whether spontaneous human motor behaviors of the less affected upper extremity (UE) early after stroke resemble the animal training model, with the potential to suppress clinical recovery. METHODS: This prospective observational study used a convenience sample of patients (n = 25, mean 4.5 ±1.8) days after stroke with a wide severity range; Controls were hospitalized for non-neurological conditions (n = 12). Outcome measures were Accelerometry, Upper-Extremity Fugl-Meyer (UEFM), Action Research Arm Test (ARAT), Shoulder Abduction/ Finger Extension Test (SAFE), NIH Stroke Scale (NIHSS). RESULTS: Accelerometry indicated total paretic UE movement was reduced compared to controls, primarily due to a 44% reduction of bilateral UE use. Unilateral paretic movement was unchanged. Thus, movement shifted early after stroke; bilateral use was reduced and unilateral use of the non-paretic UE was increased by 77%. Low correlations between movement time and motor performance prompted an exploratory factor analysis (EFA) revealing a 2-component solution; motor performance tests load on one component (motor performance) whereas accelerometry-derived variables load on a second orthogonal component (quantity of movement). CONCLUSIONS: Early after stroke, spontaneous overall UE movement is reduced, and movement shifts to unilateral use of the non-paretic UE. Two mechanisms that could influence motor recovery may already be in place 4.5 ± 1.8 days post stroke: (1) the overuse of the less affected UE, which could set the stage for learned non-use and (2) skill acquisition in the non-paretic limb that could impede recovery. Accurate UE motor assessment requires two independent constructs: motor performance and quantity of movement. These findings provide opportunities and measurement methods for studies to develop new behaviorally-based stroke recovery treatments that begin early after onset.


Assuntos
Atividade Motora/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/fisiopatologia , Acelerometria/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Destreza Motora/fisiologia , Movimento/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Paresia/fisiopatologia , Paresia/terapia , Estudos Prospectivos , Recuperação de Função Fisiológica/fisiologia , Fatores de Tempo , Estados Unidos , Extremidade Superior/fisiologia
19.
PLoS Med ; 17(7): e1003210, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32701954

RESUMO

BACKGROUND: Less than 20% of adolescents globally meet recommended levels of physical activity, and not meeting these recommended levels is associated with social disadvantage and rising disease risk. The determinants of physical activity in adolescents are multilevel and poorly understood, but the school's social environment likely plays an important role. We conducted a cluster randomised controlled trial to assess the effectiveness of a school-based programme (GoActive) to increase moderate-to-vigorous physical activity (MVPA) among adolescents. METHODS AND FINDINGS: Non-fee-paying, co-educational schools including Year 9 students in the UK counties of Cambridgeshire and Essex were eligible for inclusion. Within participating schools (n = 16), all Year 9 students were eligible and invited to participate. Participants were 2,862 13- to 14-year-olds (84% of eligible students). After baseline assessment, schools were computer-randomised, stratified by school-level pupil premium funding (below/above county-specific median) and county (control: 8 schools, 1,319 participants, mean [SD] participants per school n = 165 [62]; intervention: 8 schools, 1,543 participants, n = 193 [43]). Measurement staff were blinded to allocation. The iteratively developed, feasibility-tested 12-week intervention, aligned with self-determination theory, trained older adolescent mentors and in-class peer-leaders to encourage classes to conduct 2 new weekly activities. Students and classes gained points and rewards for engaging in any activity in or out of school. The primary outcome was average daily minutes of accelerometer-assessed MVPA at 10-month follow-up; a mixed-methods process evaluation evaluated implementation. Of 2,862 recruited participants (52.1% male), 2,167 (76%) attended 10-month follow-up measurements; we analysed the primary outcome for 1,874 participants (65.5%). At 10 months, there was a mean (SD) decrease in MVPA of 8.3 (19.3) minutes in the control group and 10.4 (22.7) minutes in the intervention group (baseline-adjusted difference [95% confidence interval] -1.91 minutes [-5.53 to 1.70], p = 0.316). The programme cost £13 per student compared with control; it was not cost-effective. Overall, 62.9% of students and 87.3% of mentors reported that GoActive was fun. Teachers and mentors commented that their roles in programme delivery were unclear. Implementation fidelity was low. The main methodological limitation of this study was the relatively affluent and ethnically homogeneous sample. CONCLUSIONS: In this study, we observed that a rigorously developed school-based intervention was no more effective than standard school practice at preventing declines in adolescent physical activity. Interdisciplinary research is required to understand educational-setting-specific implementation challenges. School leaders and authorities should be realistic about expectations of the effect of school-based physical activity promotion strategies implemented at scale. TRIAL REGISTRATION: ISRCTN Registry ISRCTN31583496.


Assuntos
Exercício Físico/psicologia , Promoção da Saúde/métodos , Serviços de Saúde Escolar/economia , Acelerometria/métodos , Adolescente , Análise Custo-Benefício , Feminino , Promoção da Saúde/economia , Humanos , Masculino , Avaliação de Programas e Projetos de Saúde , Reino Unido
20.
PLoS One ; 15(7): e0236024, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32687507

RESUMO

Training prescription and monitoring of team-sport athletes rely on accurate quantification of player movement. Our aim was to determine the sensitivity, reliability and construct validity of measures derived from a wearable device incorporating Global Positioning System (GPS) and accelerometer technology to quantify the peak periods of rugby competition. Match movement data were collected from 30 elite and 30 sub-elite rugby union players across respective competitive seasons. Accelerometer and GPS measures were analysed using a rolling average to identify peak movement for epochs ranging from 5 to 600 seconds. General linear mixed modelling was used to quantify the effects of playing position and match-half on the peak movement and variabilities within and between players represented reliability of each measure. Mean positional differences and match-half changes were assessed via standardisation and magnitude-based decisions. Sensitivity of measures was quantified via evaluation of ("signal") and typical error of measurement ("noise"). GPS and accelerometer measures had poor sensitivity for quantifying peak movement across all epochs and both levels of rugby union competition (noise 4× to 5× the signal). All measures displayed correspondingly low reliability across most epochs and both levels of competition (ICC<0.50). Construct validity was evident in mean differences between playing positions and match halves that were consistent with expected activity profiles in rugby union. However, it was clear from the pattern of differences across epoch durations and levels of competition that GPS and accelerometer measures provided different information about player movement. The poor sensitivity and low reliability of GPS and accelerometer measures of peak movement imply that rugby union players need to be monitored across many matches to obtain adequate precision for assessing individuals. Although all measures displayed construct validity, accelerometers provided meaningful information additional to that of GPS. We recommend using accelerometers alongside GPS to monitor and prescribe match respresentative training.


Assuntos
Acelerometria/métodos , Atletas/estatística & dados numéricos , Desempenho Atlético/fisiologia , Futebol Americano/fisiologia , Sistemas de Informação Geográfica/instrumentação , Corrida/fisiologia , Análise e Desempenho de Tarefas , Adulto , Humanos , Masculino , Curva ROC , Reprodutibilidade dos Testes
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