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1.
PLoS Med ; 17(9): e1003222, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32956407

RESUMO

BACKGROUND: Treatment with corticosteroids is recommended for Duchenne muscular dystrophy (DMD) patients to slow the progression of weakness. However, chronic corticosteroid treatment causes significant morbidities. Vamorolone is a first-in-class anti-inflammatory investigational drug that has shown evidence of efficacy in DMD after 24 weeks of treatment at 2.0 or 6.0 mg/kg/day. Here, open-label efficacy and safety experience of vamorolone was evaluated over a period of 18 months in trial participants with DMD. METHODS AND FINDINGS: A multicenter, open-label, 24-week trial (VBP15-003) with a 24-month long-term extension (VBP15-LTE) was conducted by the Cooperative International Neuromuscular Research Group (CINRG) and evaluated drug-related effects of vamorolone on motor outcomes and corticosteroid-associated safety concerns. The study was carried out in Canada, US, UK, Australia, Sweden, and Israel, from 2016 to 2019. This report covers the initial 24-week trial and the first 12 months of the VBP15-LTE trial (total treatment period 18 months). DMD trial participants (males, 4 to <7 years at entry) treated with 2.0 or 6.0 mg/kg/day vamorolone for the full 18-month period (n = 23) showed clinical improvement of all motor outcomes from baseline to month 18 (time to stand velocity, p = 0.012 [95% CI 0.010, 0.068 event/second]; run/walk 10 meters velocity, p < 0.001 [95% CI 0.220, 0.491 meters/second]; climb 4 stairs velocity, p = 0.001 [95% CI 0.034, 0.105 event/second]; 6-minute walk test, p = 0.001 [95% CI 31.14, 93.38 meters]; North Star Ambulatory Assessment, p < 0.001 [95% CI 2.702, 6.662 points]). Outcomes in vamorolone-treated DMD patients (n = 46) were compared to group-matched participants in the CINRG Duchenne Natural History Study (corticosteroid-naïve, n = 19; corticosteroid-treated, n = 68) over a similar 18-month period. Time to stand was not significantly different between vamorolone-treated and corticosteroid-naïve participants (p = 0.088; least squares [LS] mean 0.042 [95% CI -0.007, 0.091]), but vamorolone-treated participants showed significant improvement compared to group-matched corticosteroid-naïve participants for run/walk 10 meters velocity (p = 0.003; LS mean 0.286 [95% CI 0.104, 0.469]) and climb 4 stairs velocity (p = 0.027; LS mean 0.059 [95% CI 0.007, 0.111]). The vamorolone-related improvements were similar in magnitude to corticosteroid-related improvements. Corticosteroid-treated participants showed stunting of growth, whereas vamorolone-treated trial participants did not (p < 0.001; LS mean 15.86 [95% CI 8.51, 23.22]). Physician-reported incidences of adverse events (AEs) for Cushingoid appearance, hirsutism, weight gain, and behavior change were less for vamorolone than published incidences for prednisone and deflazacort. Key limitations to the study were the open-label design, and use of external comparators. CONCLUSIONS: We observed that vamorolone treatment was associated with improvements in some motor outcomes as compared with corticosteroid-naïve individuals over an 18-month treatment period. We found that fewer physician-reported AEs occurred with vamorolone than have been reported for treatment with prednisone and deflazacort, and that vamorolone treatment did not cause the stunting of growth seen with these corticosteroids. This Phase IIa study provides Class III evidence to support benefit of motor function in young boys with DMD treated with vamorolone 2.0 to 6.0 mg/kg/day, with a favorable safety profile. A Phase III RCT is underway to further investigate safety and efficacy. TRIAL REGISTRATION: Clinical trials were registered at www.clinicaltrials.gov, and the links to each trial are as follows (as provided in manuscript text): VBP15-002 [NCT02760264] VBP15-003 [NCT02760277] VBP15-LTE [NCT03038399].


Assuntos
Atividade Motora/efeitos dos fármacos , Distrofia Muscular de Duchenne/tratamento farmacológico , Pregnadienodiois/uso terapêutico , Corticosteroides/efeitos adversos , Criança , Pré-Escolar , Progressão da Doença , Glucocorticoides/efeitos adversos , Humanos , Masculino , Prednisona/uso terapêutico , Pregnadienodiois/metabolismo , Resultado do Tratamento , Caminhada/fisiologia
2.
Sensors (Basel) ; 20(18)2020 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-32899946

RESUMO

Gait deterioration caused by prolonged walking represents one of the main consequences of multiple sclerosis (MS). This study aims at proposing quantitative indices to measure the gait deterioration effects. The experimental protocol consisted in a 6-min walking test and it involved nine patients with MS and twenty-six healthy subjects. Pathology severity was assessed through the Expanded Disability Status Scale. Seven inertial units were used to gather lower limb kinematics. Gait variability and asymmetry were assessed by coefficient of variation (CoV) and symmetry index (SI), respectively. The evolution of ROM (range of motion), CoV, and SI was computed analyzing data divided into six 60-s subgroups. Maximum difference among subgroups and the difference between the first minute and the remaining five were computed. The indices were analyzed for intra- and inter-day reliability and repeatability. Correlation with clinical scores was also evaluated. Good to excellent reliability was found for all indices. The computed standard deviations allowed us to affirm the good repeatability of the indices. The outcomes suggested walking-related fatigue leads to an always more variable kinematics in MS, in terms of changes in ROM, increase of variability and asymmetry. The hip asymmetry strongly correlated with the clinical disability.


Assuntos
Fadiga/fisiopatologia , Transtornos Neurológicos da Marcha/diagnóstico , Marcha/fisiologia , Esclerose Múltipla/diagnóstico , Índice de Gravidade de Doença , Caminhada/fisiologia , Adulto , Idoso , Fenômenos Biomecânicos/fisiologia , Estudos de Casos e Controles , Avaliação da Deficiência , Progressão da Doença , Teste de Esforço/métodos , Feminino , Transtornos Neurológicos da Marcha/etiologia , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Reprodutibilidade dos Testes , Projetos de Pesquisa , Fatores de Tempo
3.
Proc Biol Sci ; 287(1933): 20200431, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32811308

RESUMO

Ground contact duration and stride frequency each affect muscle metabolism and help scientists link walking and running biomechanics to metabolic energy expenditure. While these parameters are often used independently, the product of ground contact duration and stride frequency (i.e. duty factor) may affect muscle contractile mechanics. Here, we sought to separate the metabolic influence of the duration of active force production, cycle frequency and duty factor. Human participants produced cyclic contractions using their soleus (which has a relatively homogeneous fibre type composition) at prescribed cycle-average ankle moments on a fixed dynamometer. Participants produced these ankle moments over short, medium and long durations while maintaining a constant cycle frequency. Overall, decreased duty factor did not affect cycle-average fascicle force (p ≥ 0.252) but did increase net metabolic power (p ≤ 0.022). Mechanistically, smaller duty factors increased maximum muscle-tendon force (p < 0.001), further stretching in-series tendons and shifting soleus fascicles to shorter lengths and faster velocities, thereby increasing soleus total active muscle volume (p < 0.001). Participant soleus total active muscle volume well-explained net metabolic power (r = 0.845; p < 0.001). Therefore, cyclically producing the same cycle-average muscle-tendon force using a decreased duty factor increases metabolic energy expenditure by eliciting less economical muscle contractile mechanics.


Assuntos
Metabolismo Energético/fisiologia , Músculo Esquelético/fisiologia , Tendões/fisiologia , Adulto , Tornozelo/fisiologia , Feminino , Marcha/fisiologia , Humanos , Masculino , Contração Muscular/fisiologia , Corrida/fisiologia , Caminhada/fisiologia
4.
PLoS One ; 15(8): e0237388, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32760167

RESUMO

INTRODUCTION: The heart rate (HR) method is a promising approach for evaluating oxygen uptake ([Formula: see text]), energy demands and exercise intensities in different forms of physical activities. It would be valuable if the HR method, established on ergometer cycling, is interchangeable with other regular activities, such as level walking. This study therefore aimed to examine the interchangeability of the HR method when estimating [Formula: see text] for ergometer cycling and level treadmill walking in submaximal conditions. METHODS: Two models of [Formula: see text] regression equations for cycle ergometer exercise (CEE) and treadmill exercise (TE) were established with 34 active commuters. Model 1 consisted of three submaximal intensities of ergometer cycling or level walking, model 2 included also one additional workload of maximal ergometer cycling or running. The regression equations were used for estimating [Formula: see text] with seven individual HR values based on 25-85% of HR reserve (HRR). The [Formula: see text] estimations were compared between CEE and TE, within and between each model. RESULTS: Only minor, and in most cases non-significant, average differences were observed when comparing the estimated [Formula: see text] levels between CEE and TE. Model 1 ranged from -0.4 to 4.8% (n.s.) between 25-85%HRR. In model 2, the differences between 25-65%HRR ranged from 1.3 to -2.7% (n.s.). At the two highest intensities, 75 and 85%HRR, [Formula: see text] was slightly lower (3.7%, 4.4%; P < 0.05), for CEE than TE. The inclusion of maximal exercise in the [Formula: see text] relationships reduced the individual [Formula: see text] variations between the two exercise modalities. CONCLUSION: The HR methods, based on submaximal ergometer cycling and level walking, are interchangeable for estimating mean [Formula: see text] levels between 25-85% of HRR. Essentially, the same applies when adding maximal exercise in the [Formula: see text] relationships. The inter-individual [Formula: see text] variation between ergometer cycling and treadmill exercise is reduced when using the HR method based on both submaximal and maximal workloads.


Assuntos
Ergometria/instrumentação , Teste de Esforço/instrumentação , Frequência Cardíaca , Caminhada/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/metabolismo
5.
Nat Commun ; 11(1): 4054, 2020 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-32792511

RESUMO

Many neurological and musculoskeletal diseases impair movement, which limits people's function and social participation. Quantitative assessment of motion is critical to medical decision-making but is currently possible only with expensive motion capture systems and highly trained personnel. Here, we present a method for predicting clinically relevant motion parameters from an ordinary video of a patient. Our machine learning models predict parameters include walking speed (r = 0.73), cadence (r = 0.79), knee flexion angle at maximum extension (r = 0.83), and Gait Deviation Index (GDI), a comprehensive metric of gait impairment (r = 0.75). These correlation values approach the theoretical limits for accuracy imposed by natural variability in these metrics within our patient population. Our methods for quantifying gait pathology with commodity cameras increase access to quantitative motion analysis in clinics and at home and enable researchers to conduct large-scale studies of neurological and musculoskeletal disorders.


Assuntos
Marcha/fisiologia , Aprendizado de Máquina , Processamento Eletrônico de Dados , Feminino , Humanos , Masculino , Redes Neurais de Computação , Caminhada/fisiologia
6.
PLoS One ; 15(8): e0231996, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857774

RESUMO

Lower-limb wearable robotic devices can improve clinical gait and reduce energetic demand in healthy populations. To help enable real-world use, we sought to examine how assistance should be applied in variable gait conditions and suggest an approach derived from knowledge of human locomotion mechanics to establish a 'roadmap' for wearable robot design. We characterized the changes in joint mechanics during walking and running across a range of incline/decline grades and then provide an analysis that informs the development of lower-limb exoskeletons capable of operating across a range of mechanical demands. We hypothesized that the distribution of limb-joint positive mechanical power would shift to the hip for incline walking and running and that the distribution of limb-joint negative mechanical power would shift to the knee for decline walking and running. Eight subjects (6M,2F) completed five walking (1.25 m s-1) trials at -8.53°, -5.71°, 0°, 5.71°, and 8.53° grade and five running (2.25 m s-1) trials at -5.71°, -2.86°, 0°, 2.86°, and 5.71° grade on a treadmill. We calculated time-varying joint moment and power output for the ankle, knee, and hip. For each gait, we examined how individual limb-joints contributed to total limb positive, negative and net power across grades. For both walking and running, changes in grade caused a redistribution of joint mechanical power generation and absorption. From level to incline walking, the ankle's contribution to limb positive power decreased from 44% on the level to 28% at 8.53° uphill grade (p < 0.0001) while the hip's contribution increased from 27% to 52% (p < 0.0001). In running, regardless of the surface gradient, the ankle was consistently the dominant source of lower-limb positive mechanical power (47-55%). In the context of our results, we outline three distinct use-modes that could be emphasized in future lower-limb exoskeleton designs 1) Energy injection: adding positive work into the gait cycle, 2) Energy extraction: removing negative work from the gait cycle, and 3) Energy transfer: extracting energy in one gait phase and then injecting it in another phase (i.e., regenerative braking).


Assuntos
Análise da Marcha/métodos , Marcha/fisiologia , Robótica/instrumentação , Adulto , Tornozelo/fisiologia , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos , Exoesqueleto Energizado/tendências , Feminino , Quadril/fisiologia , Articulação do Quadril/fisiologia , Humanos , Joelho/fisiologia , Articulação do Joelho/fisiologia , Locomoção , Extremidade Inferior/fisiologia , Masculino , Músculo Esquelético/fisiologia , Corrida/fisiologia , Caminhada/fisiologia
7.
Medicine (Baltimore) ; 99(27): e20731, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32629648

RESUMO

BACKGROUND: Backward walking (BW) training is increasingly used in rehabilitation for stroke, but relevant evidence remains unclear. OBJECTIVE: To determine the effect of BW training on patients with stroke. METHODS: A keyword search was conducted in PubMed, EMBASE, CINAHL, and China National Knowledge Infrastructure database for articles published until November, 2019. Two investigators screened the articles and extract data from each included study. Meta-analysis was performed to estimate the effect of BW on stroke. In addition, the quality of evidence was evaluated by GRADE (grading of recommendations, assessment, development, and evaluation; version:3.6) approach. RESULTS: A total of ten studies were included according to the inclusion and exclusion criteria in the review. All included studies described some positive influences of BW on stroke relative to the control group (forward walking or conventional treatment). Compared to control group, there is a statistically significant improvement for BW group in gait velocity (mean difference [MD] = 6.87, 95%CI: [1.40, 12.33], P = .01, I = 3%), Berg balance score (MD =3.82, 95%CI: [2.12, 5.52], P < .0001, I = 0%), and walk test (MD =0.11, 95%CI: [0.02, 0.20], P = .02, I = 36%). CONCLUSIONS: For patients with stroke, BW training, as an adjunct an adjunct to conventional treatment, can improve Berg balance score (moderate evidence), walk test performance (very low evidence), gait velocity (very low evidence). More large-scale and high-quality studies are warranted.


Assuntos
Reabilitação do Acidente Vascular Cerebral/métodos , Caminhada , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/fisiopatologia , Caminhada/fisiologia
8.
PLoS One ; 15(7): e0236258, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32701955

RESUMO

Parkinson's disease (PD) is a neurodegenerative disease inducing dystrophy of the motor system. Automatic movement analysis systems have potential in improving patient care by enabling personalized and more accurate adjust of treatment. These systems utilize machine learning to classify the movement properties based on the features derived from the signals. Smartphones can provide an inexpensive measurement platform with their built-in sensors for movement assessment. This study compared three feature selection and nine classification methods for identifying PD patients from control subjects based on accelerometer and gyroscope signals measured with a smartphone during a 20-step walking test. Minimum Redundancy Maximum Relevance (mRMR) and sequential feature selection with both forward (SFS) and backward (SBS) propagation directions were used in this study. The number of selected features was narrowed down from 201 to 4-15 features by applying SFS and mRMR methods. From the methods compared in this study, the highest accuracy for individual steps was achieved with SFS (7 features) and Naive Bayes classifier (accuracy 75.3%), and the second highest accuracy with SFS (4 features) and k Nearest neighbours (accuracy 75.1%). Leave-one-subject-out cross-validation was used in the analysis. For the overall classification of each subject, which was based on the majority vote of the classified steps, k Nearest Neighbors provided the most accurate result with an accuracy of 84.5% and an error rate of 15.5%. This study shows the differences in feature selection methods and classifiers and provides generalizations for optimizing methodologies for smartphone-based monitoring of PD patients. The results are promising for further developing the analysis system for longer measurements carried out in free-living conditions.


Assuntos
Teste de Esforço , Aprendizado de Máquina , Doença de Parkinson/diagnóstico , Doença de Parkinson/fisiopatologia , Smartphone , Caminhada/fisiologia , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador , Estatística como Assunto , Máquina de Vetores de Suporte
9.
Cochrane Database Syst Rev ; 7: CD009209, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32700325

RESUMO

BACKGROUND: The World Health Organization (WHO) recommends undertaking 150 minutes of moderate-intensity physical activity per week, but most people do not. Workplaces present opportunities to influence behaviour and encourage physical activity, as well as other aspects of a healthy lifestyle. A pedometer is an inexpensive device that encourages physical activity by providing feedback on daily steps, although pedometers are now being largely replaced by more sophisticated devices such as accelerometers and Smartphone apps. For this reason, this is the final update of this review. OBJECTIVES: To assess the effectiveness of pedometer interventions in the workplace for increasing physical activity and improving long-term health outcomes. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Occupational Safety and Health (OSH) UPDATE, Web of Science, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform from the earliest record to December 2016. We also consulted the reference lists of included studies and contacted study authors to identify additional records. We updated this search in May 2019, but these results have not yet been incorporated. One more study, previously identified as an ongoing study, was placed in 'Studies awaiting classification'. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of workplace interventions with a pedometer component for employed adults, compared to no or minimal interventions, or to alternative physical activity interventions. We excluded athletes and interventions using accelerometers. The primary outcome was physical activity. Studies were excluded if physical activity was not measured. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. When studies presented more than one physical activity measure, we used a pre-specified list of preferred measures to select one measure and up to three time points for analysis. When possible, follow-up measures were taken after completion of the intervention to identify lasting effects once the intervention had ceased. Given the diversity of measures found, we used ratios of means (RoMs) as standardised effect measures for physical activity. MAIN RESULTS: We included 14 studies, recruiting a total of 4762 participants. These studies were conducted in various high-income countries and in diverse workplaces (from offices to physical workplaces). Participants included both healthy populations and those at risk of chronic disease (e.g. through inactivity or overweight), with a mean age of 41 years. All studies used multi-component health promotion interventions. Eleven studies used minimal intervention controls, and four used alternative physical activity interventions. Intervention duration ranged from one week to two years, and follow-up after completion of the intervention ranged from three to ten months. Most studies and outcomes were rated at overall unclear or high risk of bias, and only one study was rated at low risk of bias. The most frequent concerns were absence of blinding and high rates of attrition. When pedometer interventions are compared to minimal interventions at follow-up points at least one month after completion of the intervention, pedometers may have no effect on physical activity (6 studies; very low-certainty evidence; no meta-analysis due to very high heterogeneity), but the effect is very uncertain. Pedometers may have effects on sedentary behaviour and on quality of life (mental health component), but these effects were very uncertain (1 study; very low-certainty evidence). Pedometer interventions may slightly reduce anthropometry (body mass index (BMI) -0.64, 95% confidence interval (CI) -1.45 to 0.18; 3 studies; low-certainty evidence). Pedometer interventions probably had little to no effect on blood pressure (systolic: -0.08 mmHg, 95% CI -3.26 to 3.11; 2 studies; moderate-certainty evidence) and may have reduced adverse effects (such as injuries; from 24 to 10 per 100 people in populations experiencing relatively frequent events; odds ratio (OR) 0.50, 95% CI 0.30 to 0.84; low-certainty evidence). No studies compared biochemical measures or disease risk scores at follow-up after completion of the intervention versus a minimal intervention. Comparison of pedometer interventions to alternative physical activity interventions at follow-up points at least one month after completion of the intervention revealed that pedometers may have an effect on physical activity, but the effect is very uncertain (1 study; very low-certainty evidence). Sedentary behaviour, anthropometry (BMI or waist circumference), blood pressure (systolic or diastolic), biochemistry (low-density lipoprotein (LDL) cholesterol, total cholesterol, or triglycerides), disease risk scores, quality of life (mental or physical health components), and adverse effects at follow-up after completion of the intervention were not compared to an alternative physical activity intervention. Some positive effects were observed immediately at completion of the intervention periods, but these effects were not consistent, and overall certainty of evidence was insufficient to assess the effectiveness of workplace pedometer interventions. AUTHORS' CONCLUSIONS: Exercise interventions can have positive effects on employee physical activity and health, although current evidence is insufficient to suggest that a pedometer-based intervention would be more effective than other options. It is important to note that over the past decade, technological advancement in accelerometers as commercial products, often freely available in Smartphones, has in many ways rendered the use of pedometers outdated. Future studies aiming to test the impact of either pedometers or accelerometers would likely find any control arm highly contaminated. Decision-makers considering allocating resources to large-scale programmes of this kind should be cautious about the expected benefits of incorporating a pedometer and should note that these effects may not be sustained over the longer term. Future studies should be designed to identify the effective components of multi-component interventions, although pedometers may not be given the highest priority (especially considering the increased availability of accelerometers). Approaches to increase the sustainability of intervention effects and behaviours over a longer term should be considered, as should more consistent measures of physical activity and health outcomes.


Assuntos
Actigrafia/instrumentação , Promoção da Saúde/métodos , Atividade Motora/fisiologia , Caminhada/fisiologia , Local de Trabalho , Adulto , Viés , Doenças Cardiovasculares/etiologia , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Comportamento Sedentário
10.
Clin Interv Aging ; 15: 1045-1056, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636619

RESUMO

Aim: This study aimed to determine the association of handgrip strength with isometric and isokinetic strength (hip, knee and ankle extensor/flexor muscles), and functional capacity in older women. Methods: The handgrip strength and lower limb strength of 199 older women (60-86 years) were measured using JAMAR and BIODEX dynamometers, respectively. Time Up and Go, Five-times-sit-to-stand and 6m-walk functional tests were evaluated. Pearson correlations were used to determine the relationship between variables. Regression analysis was applied to identify if HS was able to predict TUG performance. The effect of age was analyzed by splitting the participants in a group of older women (OLD; from 60 to 70 years old) and very old women (from 71 to 86 years old). Results: The HS and isometric/isokinetic strength correlations were negligible/low and, in most cases, were non-significant. The correlation between handgrip strength and functional tests also ranged predominantly from negligible (r=0.0 to 0.3) to low (r=0.3 to 0.5), irrespective of the group age. The handgrip strength was not able to explain the variance of the TUG performance. Conclusion: Generalizing handgrip strength as a practical and straightforward measure to determine lower limbs and overall strength, and functional capacity in older women must be viewed with caution. Handgrip strength and standard strength measures of the lower limbs and functional tests present a negligible/low correlation.


Assuntos
Força da Mão/fisiologia , Perna (Membro)/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Desempenho Físico Funcional , Idoso , Idoso de 80 Anos ou mais , Feminino , Avaliação Geriátrica/métodos , Humanos , Articulação do Joelho/fisiologia , Caminhada/fisiologia
11.
Gerontology ; 66(4): 401-408, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32623430

RESUMO

BACKGROUND: Many studies have demonstrated an inverse relationship between gait performance and cognitive impairment. The main purposes of this study were: (1) to design and validate a complex gait test (CGT) in older people, (2) to analyze the effects of age and sex on CGT, and (3) to analyze the association between CGT performance and physical functioning and cognitive measures. METHODS: A total of 279 older people (60-97 years) were analyzed in 2019. Fitness tests, gait performance, and several cognitive measures such asthe Trail-Walking Test and Montreal Cognitive Assessment were used. RESULTS: The CGT reported adequate reliability and validity parameters. In the test-retest analysis, the intra-class correlation coefficient was 0.868 (p < 0.001). There was a significant correlation between the CGT and Trail-Walking Test (r = 0.592; p < 0.001). The linear regression analysis showed that the CGT was associated with the Montreal Cognitive Assessment (R2 = 0.357; p =0.001). The binary logistic regression analysis revealed that a high CGT score was a risk factor for mild cognitive impairment (odds ratio 1.201, 95% CI 1.081-1.334; p = 0.001). The ROC curve of the mild cognitive impairment was predicted by the CGT performance (area under the curve = 0.768, 95% CI 0.647-0.889; p < 0.001), reaching the cut-off point at 20.25 s. CONCLUSIONS: The CGT showed good reliability and validity and may serve as a potential biomarker in mild cognitive impairment prediction in older adults aged 60-97 years.


Assuntos
Cognição/fisiologia , Teste de Esforço/normas , Marcha/fisiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/fisiopatologia , Estudos de Coortes , Estudos Transversais , Feminino , Avaliação Geriátrica , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores Sexuais , Espanha , Caminhada/fisiologia
12.
Medicine (Baltimore) ; 99(28): e20884, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664080

RESUMO

The objective of this work is to verify the relationship between the self-perception of health and the self-concept of physical appearance in adolescents, in order to check their influence on the physical activity they perform with the aim of preventing chronic illnesses. To this end, an observational, cross-sectional descriptive study with analytical components was carried out. Opportunistic activity, in which young people, between the ages of 16 and 22, were recruited from 5 secondary schools of the municipality of San Cristóbal de La Laguna, on the island of Tenerife (Spain). Data were collected through the General Health Questionnaire, the Rosemberg Self-esteem Scale, and the physical exercise habits test physical activity questionnaire for adolescents-A, revealing the first 2 that most percentage of responses were grouped on the positive side. The physical exercise habits test physical activity questionnaire for adolescents-A described that the most commonly performed physical activity was walking (75%).


Assuntos
Doença Crônica/prevenção & controle , Exercício Físico/psicologia , Aparência Física/fisiologia , Adolescente , Atitude Frente a Saúde , Doença Crônica/epidemiologia , Estudos Transversais , Feminino , Humanos , Estilo de Vida , Masculino , Instituições Acadêmicas/estatística & dados numéricos , Autoimagem , Espanha/epidemiologia , Inquéritos e Questionários , Caminhada/fisiologia , Caminhada/estatística & dados numéricos , Adulto Jovem
13.
PLoS One ; 15(7): e0235686, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32658907

RESUMO

Previous research found that below-knee prosthesis users proactively increase their lateral margin-of-stability on their impaired side in anticipation of an impending perturbation when the timing is predictable and potentially directed toward the impaired limb. While knowledge of perturbation timing and direction influences proactive strategies, the consequences of such knowledge and anticipatory behavior on recovery from perturbations is unclear. This study characterized center-of-mass (CoM) dynamics of below-knee prosthesis users and non-impaired controls following a lateral perturbation when the perturbation direction is known but a priori knowledge of the timing of perturbation is either known or unknown. Across groups, CoM displacement during perturbation exposure increased when directed towards the impaired or non-dominant limb with no influence of timing knowledge. In addition, peak CoM displacement was less with known timing irrespective of the perturbation direction. Generally, the CoM displacement during perturbation exposure correlated well with the CoM medial-lateral velocity during unperturbed walking, supporting evidence that human response dynamics to lateral perturbations are influenced by the instantaneous state of the body's momentum.


Assuntos
Membros Artificiais/psicologia , Equilíbrio Postural , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos , Estudos de Casos e Controles , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-32560522

RESUMO

Women experience more stress in middle age than in other life stages, and health in middle age is vital, because it influences the quality of life in old age. In this study, the effects of a forest therapy program on physiological changes in 53 middle-aged women (divided into two groups) who lived in the city were examined. One group participated in a three-day program in the forest, followed by three days in the city; the other group participated in a three-day program in the city, followed by three days in the forest. Forest experiments were conducted in a "healing forest," and urban experiments were conducted near a university campus. Blood tests were performed to evaluate the physiological effects of forest therapy. Differences in serotonin levels and vitamin D levels were verified before and after the forest (experimental group) and urban (control group) programs through paired t-tests. Statistically significant increases in serotonin levels were noted for participants in the forest program; vitamin D levels also increased, but not by statistically significant values. The findings of this study verify that forest therapy programs promote health among middle-aged women, and may prevent disease and improve quality of life.


Assuntos
Envelhecimento/fisiologia , Envelhecimento/psicologia , Florestas , Fadiga Mental , Terapias Mente-Corpo/métodos , Terapia de Relaxamento/métodos , Adaptação Psicológica/fisiologia , Adulto , Idoso , Envelhecimento/sangue , Cidades , Feminino , Promoção da Saúde/métodos , Envelhecimento Saudável/sangue , Envelhecimento Saudável/fisiologia , Envelhecimento Saudável/psicologia , Humanos , Massagem/psicologia , Meditação/psicologia , Fadiga Mental/sangue , Fadiga Mental/fisiopatologia , Fadiga Mental/psicologia , Pessoa de Meia-Idade , Terapias Mente-Corpo/psicologia , Angústia Psicológica , Qualidade de Vida/psicologia , Terapia de Relaxamento/psicologia , República da Coreia , Serotonina/sangue , Estresse Fisiológico/fisiologia , Saúde da População Urbana , População Urbana , Vitamina D/sangue , Caminhada/fisiologia , Caminhada/psicologia , Ioga/psicologia
15.
J Neuroeng Rehabil ; 17(1): 75, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32539840

RESUMO

BACKGROUND: Elastic ankle exoskeletons with intermediate stiffness springs in parallel with the human plantarflexors can reduce the metabolic cost of walking by ~ 7% at 1.25 m s- 1. In a move toward 'real-world' application, we examined whether the unpowered approach has metabolic benefit across a range of walking speeds, and if so, whether the optimal exoskeleton stiffness was speed dependent. We hypothesized that, for any walking speed, there would be an optimal ankle exoskeleton stiffness - not too compliant and not too stiff - that minimizes the user's metabolic cost. In addition, we expected the optimal stiffness to increase with walking speed. METHODS: Eleven participants walked on a level treadmill at 1.25, 1.50, and 1.75 m s- 1 while we used a state-of-the-art exoskeleton emulator to apply bilateral ankle exoskeleton assistance at five controlled rotational stiffnesses (kexo = 0, 50, 100, 150, 250 Nm rad- 1). We measured metabolic cost, lower-limb joint mechanics, and EMG of muscles crossing the ankle, knee, and hip. RESULTS: Metabolic cost was significantly reduced at the lowest exoskeleton stiffness (50 Nm rad- 1) for assisted walking at both 1.25 (4.2%; p = 0.0162) and 1.75 m s- 1 (4.7%; p = 0.0045). At these speeds, the metabolically optimal exoskeleton stiffness provided peak assistive torques of ~ 0.20 Nm kg- 1 that resulted in reduced biological ankle moment of ~ 12% and reduced soleus muscle activity of ~ 10%. We found no stiffness that could reduce the metabolic cost of walking at 1.5 m s- 1. Across all speeds, the non-weighted sum of soleus and tibialis anterior activation rate explained the change in metabolic rate due to exoskeleton assistance (p < 0.05; R2 > 0.56). CONCLUSIONS: Elastic ankle exoskeletons with low rotational stiffness reduce users' metabolic cost of walking at slow and fast but not intermediate walking speed. The relationship between the non-weighted sum of soleus and tibialis activation rate and metabolic cost (R2 > 0.56) indicates that muscle activation may drive metabolic demand. Future work using simulations and ultrasound imaging will get 'under the skin' and examine the interaction between exoskeleton stiffness and plantarflexor muscle dynamics to better inform stiffness selection in human-machine systems.


Assuntos
Metabolismo Energético/fisiologia , Exoesqueleto Energizado , Músculo Esquelético/fisiologia , Caminhada/fisiologia , Adulto , Articulação do Tornozelo/fisiologia , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Masculino
16.
J Neuroeng Rehabil ; 17(1): 81, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32586398

RESUMO

BACKGROUND: Gait training with partial body weight support (BWS) has become an established rehabilitation technique. Besides passive unloading mechanisms such as springs or counterweights, also active systems that allow rendering constant or modulated vertical forces have been proposed. However, only pilot studies have been conducted to compare different unloading or modulation strategies, and conducting experimental studies is costly and time-consuming. Simulation models that predict the influence of unloading force on human walking may help select the most promising candidates for further evaluation. However, the reliability of simulation results depends on the chosen gait model. The purpose of this paper is two-fold: First, using human experimental data, we evaluate the accuracy of some of the most prevalent walking models in replicating human walking under the influence of Constant-Force BWS: The Simplest Walking model (SW), the Spring-Loaded Inverted Pendulum model (SLIP) and the Muscle-Reflex (MR) gait model. Second, three realizations of BWS, based on Constant-Force (CF), Counterweight (CW) and Tuned-Spring (TS) approaches, are compared to each other in terms of their influence on gait parameters. METHODS: We conducted simulations in Matlab/Simulink to model the behaviour of each gait model under all three BWS conditions. Nine simulations were undertaken in total and gait parameter response was analysed in each case. Root mean square error (mrmse) w.r.t human data was used to compare the accuracy of gait models. The metrics of interest were spatiotemporal parameters and the vertical ground reaction forces. To scrutinize the BWS strategies, loss of dynamic similarity was calculated in terms of root mean square difference in gait dynamics (Δgd) with respect to the reference gait under zero unloading. The gait dynamics were characterized by a dimensionless number Modela-w. RESULTS: SLIP model showed the lowest mrmse for 6 out of 8 gait parameters and for 1 other, the mrmse value were comparable to the MR model; SW model had the highest mrmse. Out of three BWS strategies, Tuned-Spring strategies led to the lowest Δgd values. CONCLUSIONS: The results of this work demonstrate the usefulness of gait models for BWS simulation and suggest the SLIP model to be more suitable for BWS simulations than the Simplest Walker and the Muscle-reflex models. Further, the Tuned-Spring approach appears to cause less distortions to the gait pattern than the more established Counterweight and Constant-Force approaches and merits experimental verification.


Assuntos
Simulação por Computador , Transtornos Neurológicos da Marcha/reabilitação , Marcha/fisiologia , Simulação de Ausência de Peso/métodos , Benchmarking , Fenômenos Biomecânicos , Peso Corporal/fisiologia , Terapia por Exercício/métodos , Humanos , Reprodutibilidade dos Testes , Caminhada/fisiologia , Simulação de Ausência de Peso/normas
17.
J Sports Sci ; 38(17): 2021-2034, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32552580

RESUMO

Heart rate (HR), when combined with accelerometry, can dramatically improve estimates of energy expenditure and sleep. Advancements in technology, via the development and introduction of small, low-cost photoplethysmography devices embedded within wrist-worn consumer wearables, have made the collection of heart rate (HR) under free-living conditions more feasible. This systematic review and meta-analysis compared the validity of wrist-worn HR estimates to a criterion measure of HR (electrocardiography ECG or chest strap). Searches of PubMed/Medline, Web of Science, EBSCOhost, PsycINFO, and EMBASE resulted in a total of 44 articles representing 738 effect sizes across 15 different brands. Multi-level random effects meta-analyses resulted in a small mean difference (beats per min, bpm) of -0.40 bpm (95 confidence interval (CI) -1.64 to 0.83) during sleep, -0.01 bpm (-0.02 to 0.00) during rest, -0.51 bpm (-1.60 to 0.58) during treadmill activities (walking to running), while the mean difference was larger during resistance training (-7.26 bpm, -10.46 to -4.07) and cycling (-4.55 bpm, -7.24 to -1.87). Mean difference increased by 3 bpm (2.5 to 3.5) per 10 bpm increase of HR for resistance training. Wrist-worn devices that measure HR demonstrate acceptable validity compared to a criterion measure of HR for most common activities.


Assuntos
Frequência Cardíaca/fisiologia , Fotopletismografia/instrumentação , Dispositivos Eletrônicos Vestíveis , Acelerometria , Atividades Cotidianas , Ciclismo/fisiologia , Metabolismo Energético/fisiologia , Humanos , Reprodutibilidade dos Testes , Treinamento de Resistência , Descanso/fisiologia , Corrida/fisiologia , Sono/fisiologia , Caminhada/fisiologia , Punho
18.
J Frailty Aging ; 9(3): 165-171, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32588032

RESUMO

BACKGROUND: Walking interventions improve physical function, reduce fall risk, and prevent mobility disability-even in those with compromised walking ability. However, most prior studies have been conducted in controlled research settings, with no dissemination of an evidence-based walking program for older adults who have mobility limitations and/or are socially isolated. OBJECTIVES: This study reports data on the feasibility and acceptability of a community-based walking program (Walk On!) for older adults who are functionally limited, and assesses changes in physical function among attendees. The program sessions focused on long-distance walking, and took place for one-hour, for two days/week, and for 12 weeks at a time. DESIGN: Pilot implementation study. SETTING: Local church in Winston-Salem, NC. PARTICIPANTS: 49 program participants; Measurements: Physical function battery and satisfaction survey data, as well as formative evaluation data from six attendees of a focus group, are reported. RESULTS: The majority of the participants were >75 years (71%), female (65%), and presented with low levels of physical function (usual gait speed=0.79±0.16; 30.6% used an assistive device). Satisfaction with the program was high (100% would recommend it to others) and focus group results were overwhelmingly positive. Mean attendance to scheduled sessions was 77%±21%, and 63% of participants attended at least 75% of scheduled sessions (n=8 attended 100%). On average, participants improved their 6-min walk distance by 8.9%, their SPPB score by 15.4%, their timed-up-go time by 9.0%, and their usual gait speed by 11.4%. CONCLUSION: The results of the initial evaluation of Walk On! show high feasibility and acceptability of the program, as well as efficacy for improving physical function. Further research is needed to evaluate a delivery method for wider implementation of the program and to definitively test its effectiveness for improving function and other health benefits.


Assuntos
Serviços de Saúde Comunitária/organização & administração , Promoção da Saúde/organização & administração , Limitação da Mobilidade , Desenvolvimento de Programas , Caminhada , Idoso , Estudos de Viabilidade , Feminino , Grupos Focais , Humanos , Masculino , Projetos Piloto , Avaliação de Programas e Projetos de Saúde , Caminhada/fisiologia
19.
PLoS One ; 15(6): e0233510, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32492029

RESUMO

Walking stability is achieved by adjusting the medio-lateral and anterior-posterior dimensions of the base of support (step length and step width, respectively) to contain an extrapolated center of mass. We aimed to calculate total recovery time after different types of perturbations during walking, and use it to compare young and older adults following different types of perturbations. Walking trials were performed in 12 young (age 26.92 ± 3.40 years) and 12 older (age 66.83 ± 1.60 years) adults. Perturbations were introduced at different phases of the gait cycle, on both legs and in anterior-posterior or medio-lateral directions, in random order. A novel algorithm was developed to determine total recovery time values for regaining stable step length and step width parameters following the different perturbations, and compared between the two participant groups under low and high cognitive load conditions, using principal component analysis (PCA). We analyzed 829 perturbations each for step length and step width. The algorithm successfully estimated total recovery time in 91.07% of the runs. PCA and statistical comparisons showed significant differences in step length and step width recovery times between anterior-posterior and medio-lateral perturbations, but no age-related differences. Initial analyses demonstrated the feasibility of comparisons based on total recovery time calculated using our algorithm.


Assuntos
Caminhada/fisiologia , Acidentes por Quedas/prevenção & controle , Adulto , Idoso , Envelhecimento/fisiologia , Envelhecimento/psicologia , Algoritmos , Fenômenos Biomecânicos , Cognição , Estudos de Viabilidade , Feminino , Marcha/fisiologia , Análise da Marcha/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Projetos Piloto , Equilíbrio Postural/fisiologia , Análise de Componente Principal , Análise e Desempenho de Tarefas , Fatores de Tempo , Caminhada/psicologia , Adulto Jovem
20.
Nihon Ronen Igakkai Zasshi ; 57(2): 155-162, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32475943

RESUMO

AIM: In recent years in Japan, forest therapies have been implemented in various places. While the effects of such therapies have been reported in previous research papers, those of artificial gardens have not been clarified. At the 2018 Yamaguchi Yume Flower Expo, the Yamaguchi University Faculty of Medicine had the opportunity to provide a "Well-being Garden" in collaboration with the Japan Landscape Contractors Association Yamaguchi Prefecture Branch. We examined the physical and mental responses of older people who strolled in the Well-being Garden. METHODS: Participants were 158 people ≥ 65 years old. Pre-and post-stroll interviews were conducted, and the heart rate, blood pressure, and autonomic nervous activities were measured. RESULTS: After strolling in the garden, the heart rate significantly decreased from 76.1±12.9 to 73.9±11.8/min (p<0.01), and both the systolic and diastolic blood pressure significantly decreased from 142.5±24.4 to 139.4±24.1 mmHg and from 83.7±12.0 to 81.5±11.9 mmHg, respectively (p<0.01). The ralue of low frequency/high frequency (LF/HF) after strolling in the garden came closer to the standard one than before, both in the participants with much tension and with less tension. In the post-stroll interview, 74 reported feeling very good, and 84 felt good. CONCLUSIONS: These results suggested that strolling in the Well-being Garden positively influenced the physical and mental condition of the participants.


Assuntos
Afeto , Sistema Nervoso Autônomo/fisiologia , Jardins , Caminhada/fisiologia , Caminhada/psicologia , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Flores , Frequência Cardíaca , Humanos , Japão
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