Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 450
Filtrar
1.
J Sports Sci ; 38(1): 114-120, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31665975

RESUMO

Sedentary time (ST) has been inconsistently associated with adiposity and cardiorespiratory fitness in children in previous studies. We studied cross-sectional associations of ST, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) with fat mass index (FMI) and cardiorespiratory fitness (estimated VO2max). Associations were evaluated with and without considering pattern of ST by bout length. We measured ST and activity by a wrist-worn accelerometer, FMI by bioelectrical impedance, and VO2max by Pacer test in 443 children (51.2% girls, 10.2 ± 0.6 years). Isotemporal substitution regression models estimated the effects of substituting ST, LPA, and MVPA on FMI and VO2max. Further models repeated analyses separating ST into short (<10 min) and long (≥10 min) bouts. Only replacing ST or LPA with MVPA was consistently associated with lower FMI and greater VO2max. When separated by bout length, only one unique association was found where replacing long ST bouts with short ST bouts was associated with lower FMI in girls only. In conclusion, activity pattern is associated with adiposity in girls and fitness in boys and girls. Separating ST into long and short ST bouts may be of minimal importance when assessing associations with adiposity and fitness using wrist-worn accelerometry in children.


Assuntos
Acelerometria/instrumentação , Adiposidade/fisiologia , Aptidão Cardiorrespiratória , Exercício/fisiologia , Monitores de Aptidão Física , Comportamento Sedentário , Índice de Massa Corporal , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Fatores de Tempo
2.
J Sports Sci ; 38(2): 150-158, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31699000

RESUMO

Application of machine learning techniques has the potential to yield unseen insights into movement and permits visualisation of complex behaviours and tangible profiles. The aim of this study was to identify profiles of relative motor competence (MC) and movement behaviours in pre-school children using novel analytics. One-hundred and twenty-five children (4.3 ± 0.5y, 1.04 ± 0.05 m, 17.8 ± 3.2 kg, BMI: 16.2 ± 1.9 kg.m2) took part in this study. Measures included accelerometer-derived 24-h activity, MC (Movement Assessment Battery for Children second edition), height, weight and waist circumference, from which zBMI were derived. Self-Organised Map (SOM) analysis was used to classify participants' profiles and a k-means cluster analysis was used to classify the neurons into larger groups according to the input variables. These clusters were used to describe the individuals' characteristics according to their MC and PA compositions. The SOM analysis indicated five profiles according to MC and PA. One cluster was identified as having both the lowest MC and MVPA (profile 2), whilst profiles 4 and 5 show moderate-high values of PA and MC. We present a novel pathway to profiling complex tenets of human movement and behaviour, which has never previously been implemented in pre-school children, highlighting that the focus should change from obesity monitoring, to "moving well".Abbreviations: MC: Motor competence; PA: Physical activity; MVPA: Moderate-to-vigorous physical activity; SOM: Self-organized map; BMI: Body mass index; MABC2: Movement assessment battery for children 2nd edition; MANOVA: Multiple analysis of variance.


Assuntos
Exercício/fisiologia , Aprendizado de Máquina , Atividade Motora/fisiologia , Acelerometria/instrumentação , Índice de Massa Corporal , Pré-Escolar , Estudos Transversais , Feminino , Monitores de Aptidão Física , Humanos , Masculino , Movimento/fisiologia
3.
Sports Health ; 12(1): 66-73, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31469616

RESUMO

BACKGROUND: The relationship of training load to injury using wearable technology has not been investigated in professional American football players. The primary objective of this study was to determine the correlation between player workload and soft tissue injury over the course of a football season utilizing wearable global positioning system (GPS) technology. HYPOTHESIS: Increased training load is associated with a higher incidence of soft tissue injuries. STUDY DESIGN: Case-control study. LEVEL OF EVIDENCE: Level 3. METHODS: Player workloads were assessed during preseason and regular-season practice sessions using GPS tracking and triaxial accelerometry from 2014 to 2016. Soft tissue injuries were recorded during each season. Player workload during the week of injury (acute) and average weekly workload during the 4 weeks (chronic) prior to injury were determined for each injury and in uninjured position-matched controls during the same week. A matched-pairs t test was used to determine differences in player workload. Subgroup analysis was also conducted to determine whether observed effects were confounded by training period and type of injury. RESULTS: In total, 136 lower extremity injuries were recorded. Of the recorded injuries, 101 injuries with complete GPS and clinical data were included in the analysis. Injuries were associated with greater increases in workload during the week of injury over the prior month when compared with uninjured controls. Injured players saw a 111% (95% CI, 66%-156%) increase in workload whereas uninjured players saw a 73% (95% CI, 34%-112%) increase in workload during the week of injury (P = 0.032). Individuals who had an acute to chronic workload ratio higher than 1.6 were 1.5 times more likely to sustain an injury relative to time- and position-matched controls (64.6% vs 43.1%; P = 0.004). CONCLUSION: Soft tissue injuries in professional football players were associated with sudden increases in training load over the course of a month. This effect seems to be especially pronounced during the preseason when player workloads are generally higher. These results suggest that a gradual increase of training intensity is a potential method to reduce the risk of soft tissue injury. CLINICAL RELEVANCE: Preseason versus regular-season specific training programs monitored with wearable technology may assist team athletic training and medical staff in developing programs to optimize player performance.


Assuntos
Acelerometria/instrumentação , Comportamento Competitivo/fisiologia , Monitores de Aptidão Física , Futebol Americano/lesões , Condicionamento Físico Humano/efeitos adversos , Condicionamento Físico Humano/métodos , Lesões dos Tecidos Moles/etiologia , Adulto , Estudos de Casos e Controles , Humanos , Estudos Longitudinais , Extremidade Inferior/lesões , Masculino , Estudos Retrospectivos , Fatores de Risco , Lesões dos Tecidos Moles/prevenção & controle , Adulto Jovem
4.
J Sports Sci ; 38(2): 214-230, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31795815

RESUMO

Injuries and lack of motivation are common reasons for discontinuation of running. Real-time feedback from wearables can reduce discontinuation by reducing injury risk and improving performance and motivation. There are however several limitations and challenges with current real-time feedback approaches. We discuss these limitations and challenges and provide a framework to optimise real-time feedback for reducing injury risk and improving performance and motivation. We first discuss the reasons why individuals run and propose that feedback targeted to these reasons can improve motivation and compliance. Secondly, we review the association of running technique and running workload with injuries and performance and we elaborate how real-time feedback on running technique and workload can be applied to reduce injury risk and improve performance and motivation. We also review different feedback modalities and motor learning feedback strategies and their application to real-time feedback. Briefly, the most effective feedback modality and frequency differ between variables and individuals, but a combination of modalities and mixture of real-time and delayed feedback is most effective. Moreover, feedback promoting perceived competence, autonomy and an external focus can improve motivation, learning and performance. Although the focus is on wearables, the challenges and practical applications are also relevant for laboratory-based gait retraining.


Assuntos
Desempenho Atlético/fisiologia , Desempenho Atlético/psicologia , Retroalimentação , Monitores de Aptidão Física , Motivação , Corrida/fisiologia , Corrida/psicologia , Traumatismos em Atletas/prevenção & controle , Fenômenos Biomecânicos , Marcha/fisiologia , Humanos , Percepção , Corrida/lesões
5.
Clin Interv Aging ; 14: 1817-1828, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31695350

RESUMO

Background: Physical exercise is associated with decreased cardiovascular disease (CVD) risk, but recent large-scale trials suggest that exercise alone is insufficient to reduce CVD events in high-risk older adults. Purpose: This pilot randomized clinical trial aimed to collect critical data on feasibility, safety, and protocol integrity necessary to design a fully powered randomized controlled trial (RCT) and evaluate the impact of combining structured exercise with an intervention designed to enhance non-exercise physical activity (EX+NEPA) compared to EX alone. Methods: Forty participants aged ≥60 years with moderate-to-high risk of coronary heart disease events were randomly assigned to either the EX+NEPA or EX groups and followed for 20 weeks. Both groups underwent a twice-weekly, 8-week center-based exercise intervention with aerobic and resistance exercises. EX+NEPA group also received a wearable activity tracking device along with behavioral monitoring and feedback throughout the study. Study outcomes were evaluated at 8 and 20 weeks. Results: Data are presented as adjusted mean change of the differences over time with 95% confidence intervals at 20 weeks. Relative to EX, the change in steps/day at 20 weeks was 1994 (-40.27, 4028) higher for EX+NEPA. For sedentary time at close-out, the EX+NEPA group was -6.8 (-45.2, 31.6) min/day relative to EX. The between-group differences for systolic and diastolic blood pressure were -9.9 (-19.6, -0.3) and -1.8 (-6.9, 3.3) mmHg, respectively. Conclusion: The addition of wearable technology intervention appeared to positively influence daily activity patterns and changes in blood pressure - potentially improving risk factors for CVD. A fully powered randomized trial is needed to ultimately test this hypothesis.


Assuntos
Doença da Artéria Coronariana/prevenção & controle , Exercício , Monitores de Aptidão Física , Comportamento Sedentário , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Exercício/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Fatores de Risco , Fatores de Tempo
6.
J Sports Sci ; 37(23): 2751-2758, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31506039

RESUMO

This study used the intensity gradient (IG) and average acceleration metrics to describe children's activity profiles and explore associations with body mass index (BMI) z-score. Two hundred and forty-six children (n = 138 girls) aged 9.6 ± 1.4 years wore a wrist-mounted ActiGraph wGT3X-BT accelerometer for 7 days on their non-dominant wrist. Physical activity (PA) metrics captured included: the IG which describes the intensity distribution of accelerations across the 24 h monitoring period; average acceleration which provides a measure of the volume of activity; total moderate-to-vigorous PA (MVPA) and inactive time. Acceleration was averaged over 5s epochs. Finally, BMI z-score was calculated for each participant. Average acceleration was negatively associated with BMI z-score (p < 0.05) independent of age and gender but not IG. The IG was negatively associated with BMI z-score independent of potential correlates and average acceleration. Total MVPA was not associated with BMI-z score. The IG and average acceleration metrics may be used to explore the independent or cumulative effects of the volume and intensity distribution of activity upon measures of health and well-being in children to inform specific activity recommendations.


Assuntos
Índice de Massa Corporal , Exercício/fisiologia , Aceleração , Actigrafia/instrumentação , Criança , Estudos Transversais , Feminino , Monitores de Aptidão Física , Humanos , Masculino , Análise de Regressão , Corrida/fisiologia , Comportamento Sedentário , Velocidade de Caminhada/fisiologia
7.
Sports Health ; 11(6): 535-542, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31478791

RESUMO

BACKGROUND: The variability of throwing metrics, particularly elbow torque and ball velocity, during structured long-toss programs is unknown. HYPOTHESES: (1) Elbow torque and ball velocity would increase as throwers progressed through a structured long-toss program and (2) intrathrower reliability would be high while interthrower reliability would be variable. STUDY DESIGN: Descriptive laboratory study. LEVEL OF EVIDENCE: Level 3. METHODS: Sixty healthy high school and collegiate pitchers participated in a structured long-toss program while wearing a validated inertial measurement unit, which measured arm slot, arm velocity, shoulder rotation, and elbow varus torque. Ball velocity was assessed by radar gun. These metrics were compared within and between all pitchers at 90, 120, 150, and 180 ft and maximum effort mound pitching. Intra- and interthrower reliabilities were calculated for each metric at every stage of the program. RESULTS: Ball velocity significantly changed at each progressive throwing distance, but elbow torque did not. Pitching from the mound did not place more torque on the elbow than long-toss throwing from 120 ft and beyond. Intrathrower reliability was excellent (intraclass correlation coefficient >0.75) throughout the progressive long-toss program, especially on the mound. Ninety-one percent of throwers had acceptable interthrower reliability (coefficient of variation <5%) for ball velocity, whereas only 79% of throwers had acceptable interthrower reliability for elbow torque. CONCLUSION: Based on trends in elbow torque, it may be practical to incorporate pitching from the mound earlier in the program (once a player is comfortable throwing from 120 ft). Ball velocity and elbow torque do not necessarily correlate with one another, so a degree of caution should be exercised when using radar guns to estimate elbow torque. Given the variability in elbow torque between throwers, some athletes would likely benefit from an individualized throwing program. CLINICAL RELEVANCE: Increased ball velocity does not necessarily equate to increased elbow torque in long-toss. Some individuals would likely benefit from individualized long-toss programs for rehabilitation.


Assuntos
Beisebol/fisiologia , Cotovelo/fisiologia , Condicionamento Físico Humano/métodos , Braço/fisiologia , Traumatismos em Atletas/reabilitação , Beisebol/lesões , Fenômenos Biomecânicos , Monitores de Aptidão Física , Humanos , Rotação , Ombro/fisiologia , Equipamentos Esportivos , Torque , Exercício de Aquecimento , Dispositivos Eletrônicos Vestíveis , Adulto Jovem
8.
Artigo em Inglês | MEDLINE | ID: mdl-31487812

RESUMO

In recent years, IoT (Internet of Things)-based smart devices have penetrated a wide range of markets, including connected health, smart home, and wearable devices. Among the IoT-based smart devices, wearable fitness trackers are the most widely diffused and adopted IoT based devices. Such devices can monitor or track the physical activity of the person wearing them. Although society has benefitted from the conveniences provided by IoT-based wearable fitness trackers, few studies have explored the factors influencing the adoption of such technology. Furthermore, one of the most prevalent issues nowadays is the large attrition rate of consumers no longer wearing their device. Consequently, this article aims to define an analytic framework that can be used to explore the factors that influence the adoption of IoT-based wearable fitness trackers. In this article, the constructs for evaluating these factors will be explored by reviewing extant studies and theories. Then, these constructs are further evaluated based on experts' consensus using the modified Delphi method. Based on the opinions of experts, the analytic framework for deriving an influence relationship map (IRM) is derived using the decision-making trial and evaluation laboratory (DEMATEL). Finally, based on the IRM, the behaviors adopted by mass customers toward IoT-based wearable fitness trackers are confirmed using the partial least squares (PLS) structural equation model (SEM) approach. The proposed analytic framework that integrates the DEMATEL and PLS-SEM was verified as being a feasible research area by empirical validation that was based on opinions provided by both Taiwanese experts and mass customers. The proposed analytic method can be used in future studies of technology marketing and consumer behaviors.


Assuntos
Comportamento do Consumidor , Tomada de Decisões , Monitores de Aptidão Física/estatística & dados numéricos , Monitorização Fisiológica/psicologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Adulto Jovem
9.
J Sports Sci ; 37(23): 2720-2725, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31480895

RESUMO

Objective: To explore whether basketball player's self-determined motivation interacts with environmental contexts and coach training to influence percentage time in moderate-to-vigorous physical activity (%MVPA). Methods: A secondary analysis of data from 76 girls (mean ± SD, 10.5 ± 1.0 years) was conducted. Players were classified as high self-determined motivation (HSDM) or low self-determined motivation (LSDM) and randomised to trained (intervention) or untrained (control) coaches. Training included 2 workshops on strategies for activity-promoting practices. Girls were exposed to environmental contexts (practices and games) led by a trained/untrained coach (depending on arm) and one without coaches (free time) daily. Girls wore accelerometers each day. Using mixed random-effects models, the influence of motivation, context and training on %MVPA was analysed. Results: Trained coaches' practices were associated with the greatest %MVPA with no difference between HSDM and LSDM players (38.28 ± 1.77%; 37.64 ± 1.80%; p = 0.66). HSDM players had significantly greater %MVPA versus LSDM players during untrained coaches' practices (23.58 ± 1.77%; 20.51 ± 1.78%; p = 0.03). During games with trained coaches, HSDM players had greater %MVPA compared to LSDM players (23.79 ± 1.76%; 18.56 ± 1.74%; p < 0.001). No between-group difference in %MVPA during free time was found (12.85 ± 0.82%; 13.39 ± 0.84%; p = 0.64). Conclusion: The impact of individual differences in self-determined motivation on %MVPA during practices was attenuated when coaches were trained to implement activity-promoting practices.


Assuntos
Basquetebol/psicologia , Meio Ambiente , Tutoria , Motivação , Acelerometria/instrumentação , Criança , Feminino , Monitores de Aptidão Física , Humanos , Individualidade , Fatores de Tempo , Esportes Juvenis/fisiologia
10.
Int J Sports Med ; 40(12): 756-761, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31476782

RESUMO

We studied the effects of supramaximal interval exercise (SIE) with or without antihypertensive medication (AHM) on 21-hr blood pressure (BP) response. Twelve hypertensive patients chronically medicated with AHM, underwent three trials in a randomized order: a) control trial without exercise and substituting their AHM with a placebo (PLAC); b) placebo medicine and a morning bout of SIE (PLAC+SIE), and c) combining AHM and exercise (AHM+SIE). Acute and ambulatory blood pressure responses were measured for 21-hr after treatment. 20 min after treatment, systolic blood pressure (SBP) readings were reduced, similar to readings after PLAC+SIE (-9.7±6.0 mmHg, P<0.001) and AHM+SIE (-10.4±7.9 mmHg, P=0.001). 21 h after treatment, SBP remained reduced after PLAC+SIE (125±12 mmHg, P=0.022) and AHM+SIE (122±12 mmHg, P=0.013) compared to PLAC (132±16 mmHg). The BP reduction in PLAC+SIE faded out at 4 a.m., while in AHM+SIE it continued overnight. At night, BP reduction was larger in AHM+SIE than PLAC+SIE (-5.6±4.0 mmHg, P=0.006). Our data shows that a bout of supramaximal aerobic interval exercise in combination with ARB medication in the morning elicits a sustained blood pressure reduction lasting at least 21-h. Thus, the combination of exercise and angiotensin receptor blocker medication seems superior to exercise alone for acutely decreasing blood pressure.


Assuntos
Anti-Hipertensivos/uso terapêutico , Treinamento Intervalado de Alta Intensidade , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Hipotensão Pós-Exercício/fisiopatologia , Actigrafia/métodos , Idoso , Pressão Sanguínea/fisiologia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Monitores de Aptidão Física , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Postura/fisiologia , Estudos de Tempo e Movimento
11.
Int J Radiat Oncol Biol Phys ; 105(4): 745-751, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31398385

RESUMO

PURPOSE: Here we explore the prognostic value of baseline step count data captured using wearable devices for patients treated with definitive chemoradiation therapy for locally advanced non-small cell lung cancer (NSCLC). METHODS AND MATERIALS: Patients with locally advanced NSCLC wore a commercial fitness tracker during a course of definitive, concurrent chemoradiation therapy as part of a clinical trial. Baseline step count average was defined as the average daily step total from study enrollment until completion of the first week of radiation therapy. Based on data from healthy individuals, study subjects were categorized as inactive (below the 25th percentile), moderately active (25th to 75th percentile), or highly active (above the 75th percentile). Fisher's exact test was used to examine activity level as a predictor of hospitalization during radiation therapy and of completing the planned radiation therapy course without delay exceeding 1 week. Median progression-free survival (PFS) and overall survival (OS) durations were estimated using the Kaplan-Meier method. Inactivity was tested as a predictor of PFS and OS using Cox proportional hazards models. RESULTS: Fifty subjects met eligibility criteria. Nine (18%) were categorized as highly active, 23 (46%) were moderately active, and 18 (36%) were inactive. Inactive subjects were more likely to be hospitalized during the radiation therapy course than other subjects (50% vs 9%, P = .004) and less likely to complete radiation therapy without delay exceeding 1 week (67% vs 97%, P = .006). Median PFS duration was 5.3 months for inactive subjects and 18.3 months for others (hazard ratio for inactivity = 5.10, P < .001). Median OS duration was 15.0 months for inactive subjects and not reached for others (hazard ratio = 3.91, P = .004). Performance status was not a significant predictor of PFS or OS. CONCLUSIONS: Baseline activity level measured using wearable devices may help identify patients with NSCLC who are fit for concurrent chemoradiation therapy and can predict clinical outcomes in this setting.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Monitores de Aptidão Física/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Neoplasias Pulmonares/radioterapia , Caminhada , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Quimiorradioterapia , Fracionamento da Dose de Radiação , Exercício , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Estudos Prospectivos , Comportamento Sedentário , Fatores de Tempo
12.
Int J Behav Med ; 26(5): 562-568, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31372835

RESUMO

BACKGROUND: Research has demonstrated a correlational relationship between sleep and physical activity, though this work has been largely cross sectional and fails to demonstrate temporal relationships. The purpose of this study was to test the daily, bidirectional relationships between sleep and physical activity, and whether this varied between weekdays and weekend days. METHOD: Fifty-four healthy, young adults wore a Fitbit Flex to measure sleep and physical activity during a 6-day study period. RESULTS: Mixed linear models revealed that physical activity did not predict subsequent night's sleep. However, on nights when participants had longer than their own average total sleep time, and greater than their own average wake after sleep onset, this predicted less physical activity the following day. CONCLUSION: Results suggest that, in healthy young adults, physical activity may not promote healthier subsequent sleep, but sleep duration and continuity influence physical activity in their own way. Young adults may respond differently to health promotion efforts, and a greater understanding of these temporal associations can enhance the efficacy of these efforts.


Assuntos
Exercício/fisiologia , Monitores de Aptidão Física , Sono/fisiologia , Adolescente , Feminino , Humanos , Masculino , Adulto Jovem
13.
Int J Behav Nutr Phys Act ; 16(1): 65, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31419998

RESUMO

BACKGROUND: Pooling data from thigh-worn accelerometers across multiple studies has great potential to advance evidence on the health benefits of physical activity. This requires harmonization of information on body postures, physical activity types, volumes and time patterns across different brands of devices. The aim of this study is to compare the physical behavior estimates provided by three different brands of thigh-worn accelerometers. METHODS: Twenty participants volunteered for a 7-day free-living measurement. Three accelerometers - ActiGraph GT3X+, Axivity AX3 and ActivPAL Micro4 - were randomly placed in a vertical line on the midsection of the right thigh. Raw data from each accelerometer was processed and classified into 8 physical activities and postures using the Acti4 software. Absolute differences between estimates and the respective coefficient of variation (CV) were calculated. RESULTS: We observed very minor differences between physical behavior estimates from three different accelerometer brands. When averaged over 24 h (1,440 min), the absolute difference (CV) between accelerometers were: 1.2 mins (0.001) for lying/sitting, 3.4 mins (0.02) for standing, 3.5 mins (0.06) for moving, 1.9 mins (0.03) for walking, 0.1 mins (0.19) for running, 1.2 mins (0.19) for stair climbing, 1.9 mins (0.07) for cycling. Moreover, there was an average absolute difference of 282 steps (0.03) per 24 h. CONCLUSIONS: Physical behaviors were classified with negligible difference between the accelerometer brands. These results support harmonization of data from different thigh-worn accelerometers across multiple cohorts when analyzed in an identical manner.


Assuntos
Acelerometria/instrumentação , Exercício/fisiologia , Monitores de Aptidão Física , Monitorização Ambulatorial/instrumentação , Sono/fisiologia , Humanos , Postura/fisiologia , Software , Coxa da Perna/fisiologia
14.
Int J Behav Nutr Phys Act ; 16(1): 66, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31420000

RESUMO

BACKGROUND: Physical activity has beneficial effects on the health of cancer survivors. We aimed to investigate accelerometer-assessed physical activity and sedentary time in cancer survivors, and describe activity profiles. Additionally, we identify demographic and clinical correlates of physical activity, sedentary time and activity profiles. METHODS: Accelerometer, questionnaire and clinical data from eight studies conducted in four countries (n = 1447) were pooled. We calculated sedentary time and time spent in physical activity at various intensities using Freedson cut-points. We used latent profile analysis to identify activity profiles, and multilevel linear regression analyses to identify demographic and clinical variables associated with accelerometer-assessed moderate to vigorous physical activity (MVPA), sedentary time, the highly active and highly sedentary profile, adjusting for confounders identified using a directed acyclic graph. RESULTS: Participants spent on average 26 min (3%) in MVPA and 568 min (66%) sedentary per day. We identified six activity profiles. Older participants, smokers and participants with obesity had significantly lower MVPA and higher sedentary time. Furthermore, men had significantly higher MVPA and sedentary time than women and participants who reported less fatigue had higher MVPA time. The highly active profile included survivors with high education level and normal body mass index. Haematological cancer survivors were less likely to have a highly active profile compared to breast cancer survivors. The highly sedentary profile included older participants, males, participants who were not married, obese, smokers, and those < 12 months after diagnosis. CONCLUSIONS: Cancer survivors engage in few minutes of MVPA and spend a large proportion of their day sedentary. Correlates of MVPA, sedentary time and activity profiles can be used to identify cancer survivors at risk for a sedentary and inactive lifestyle.


Assuntos
Sobreviventes de Câncer/estatística & dados numéricos , Exercício , Comportamento Sedentário , Acelerometria , Estudos de Coortes , Feminino , Monitores de Aptidão Física , Humanos , Masculino
15.
Int J Med Inform ; 130: 103948, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31442846

RESUMO

With the emergence of an always-on culture and the private smartphones always within reach, professional and recreational contexts overlap. Little empirical knowledge is available on prevailing online habits among healthcare personnel and whether gender matters in this context. To investigate health technology-related preferences, we conducted an online survey among a purposive sample of employees and students at the Medical University of Vienna, Austria. In total, 905 participants (59.0%, 540/905, females) provided self-reported information on use of online services and mobile health applications (apps) as well as respective gender-specific internal and external apperceptions. Mann-Whitney U tests and binary regression analysis assessed respective gender differences. The structured German questionnaire was validated by principal component analysis. The study found a moderate familiarity with health technologies. As for gender differences, prevailing health app use was high among both male and female participants (39, 141/365, and 42%, 229/540, respectively), with apps for tracking activity and nutrition habits most commonly used. Approval for monitoring health and lifestyle parameters, eHealth and telemedicine knowledge levels, and online health information retrieval predicted health app use, whereas gender did not. Socio-demographic attributes including gender influence not only private online habits of users, but might also affect acceptance of health technologies and their professional use in a clinical setting. Thus, addressing the gender dimension already in concept stages of digital devices and services for healthcare and lifestyle could speed up private and public adoption of health technologies.


Assuntos
Tecnologia Biomédica/estatística & dados numéricos , Monitores de Aptidão Física/estatística & dados numéricos , Corpo Clínico/psicologia , Aplicativos Móveis/estatística & dados numéricos , Smartphone/estatística & dados numéricos , Estudantes/psicologia , Adulto , Áustria , Estudos Transversais , Feminino , Humanos , Masculino , Fatores Sexuais , Inquéritos e Questionários , Telemedicina/estatística & dados numéricos , Universidades
16.
Artigo em Inglês | MEDLINE | ID: mdl-31443347

RESUMO

Activity trackers are a simple and mostly low-priced method to capture physiological parameters. Despite the high number of wrist-worn devices, there is a lack of scientific validation. The purpose of this study was to assess whether the activity trackers represent a valid alternative to gold-standard methods in terms of estimating energy expenditure (EE) and maximum oxygen uptake (VO2max). Twenty-four healthy subjects participated in this study. In total, five commercially available wrist-worn devices were tested with regard to their validity of EE and/or VO2max. Estimated values were compared with indirect calorimetry. Validity of the activity trackers was determined by paired sample t-tests, mean absolute percentage errors (MAPE), Intraclass Correlation Coefficient, and Bland-Altman plots. Within the tested devices, differences in scattering in VO2max and EE could be observed. This results in a MAPE > 10% for all evaluations, except for the VO2max-estimation of the Garmin Forerunner 920XT (7.3%). The latter significantly underestimates the VO2max (t(23) = -2.37, p = 0.027), whereas the Garmin Vivosmart HR significantly overestimates the EE (t(23) = 2.44, p = 0.023). The tested devices did not show valid results concerning the estimation of VO2max and EE. Hence, the current wrist-worn activity trackers are most likely not accurate enough to be used for neither purposes in sports, nor in health care applications.


Assuntos
Metabolismo Energético , Monitores de Aptidão Física/estatística & dados numéricos , Consumo de Oxigênio , Adulto , Feminino , Alemanha , Humanos , Masculino , Reprodutibilidade dos Testes , Punho , Adulto Jovem
17.
Int. j. cardiovasc. sci. (Impr.) ; 32(4): 396-407, July-Aug. 2019. graf, ilus
Artigo em Inglês | LILACS | ID: biblio-1012340

RESUMO

The use of technology has increased tremendously, by means of more reliable, smaller, more accessible and specially more user-friendly devices, which provide a wider range of features, and promote significant benefits for the population and health professionals. It is in this context that monitors and apps for heart rate (HR) measurement have emerged. HR is a clinical vital sign of diagnostic and prognostic importance. In response to body movement, HR tends to increase, in a direct relationship with the intensity of exercise. HR was primarily measured by the count of arterial pulse, and recently, HR can be precisely measured by monitors, bracelets and smartphone apps capable to perform real-time measurements and storage of data. This paper aimed to make a brief and updated review on the theme, providing a broader view of advantages and limitations of these resources for HR measurement in exercise. HR monitors and apps use basically two types of technology, optical sensor (photoplethysmography) and electrical signal from the heart. In general, these devices have shown good accuracy in measuring HR and HR variability at rest, but there are differences between brands and models considering the type, mode and intensity of exercise. HR measurements by monitors and smartphone apps are simple, accessible and may help cardiologists in the monitoring of the intensity of aerobic exercise, focusing on health promotion and on primary and secondary prevention of cardiovascular diseases


Assuntos
Humanos , Masculino , Feminino , Palpação/métodos , Exercício , Monitores de Aptidão Física , Frequência Cardíaca , Arritmias Cardíacas , Prognóstico , Esportes , Débito Cardíaco , Doenças Cardiovasculares/diagnóstico , Tecnologia Biomédica , Teste de Esforço/métodos
18.
J Sports Sci ; 37(22): 2538-2548, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31352866

RESUMO

This study investigates the role of Perceived Athletic Competence (PAC) and Health-Related Fitness (HRF) in mediating the reciprocal relationship between Motor Competence (MC) and Physical Activity (PA) during the transition from primary to secondary school. MC, PA, PAC and HRF were measured in 224 participants (baseline age 12.26 ± .037 years; 51% female) in final year of primary school and one year later in first year of secondary school. Path analysis in AMOS 23 was used to test the mediating influence of PAC and HRF on the MC-PA relationship. Fit indices showed that, in both directions, HRF and PAC mediated the relationship between MC and PA (PA predicting MC; χ2 = 3.91, p = .272, CFI = .99, RMSEA = .04. MC predicting PA: χ2 = 6.46, p = .167, CFI = .99, RMSEA = .04). Pathways were stronger through HRF than through PAC, indicating that HRF is the more substantial mediator of the MC-PA relationship during the school transition. Pathways were stronger in the direction of PA predicting MC than in the reverse direction. Interventions seeking to influence PA and MC across the school transition should focus on HRF as it is a primary mediator of the MC-PA relationship.


Assuntos
Desempenho Atlético/psicologia , Destreza Motora/fisiologia , Percepção , Aptidão Física/psicologia , Acelerometria/instrumentação , Adolescente , Criança , Exercício/psicologia , Feminino , Monitores de Aptidão Física , Humanos , Masculino , Instituições Acadêmicas , Fatores Sexuais
19.
Gait Posture ; 73: 140-146, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31325738

RESUMO

PURPOSE: Standing up, sitting down and walking require considerable effort and coordination, which are crucial indicators to rehabilitation (e.g. stroke), and in older populations may indicate the onset of frailty and physical and cognitive decline. Currently, there are few reports robustly quantifying sit-to-stand and stand-to-sit transitions in free-living environments. The aim of this study was to identify and quantify these transitions using the peak velocity of sit-to-stand and stand-to-sit transitions to determine if these velocities were different in a healthy cohort and a mobility-impaired population. METHODS: Free-living sit-to-stand and stand-to-sit acceleration data were recorded from 21 healthy volunteers and 34 stroke survivors using activPAL3™ monitors over a one-week period. Thigh inclination velocity was calculated from these accelerometer data. Maximum velocities were compared between populations. RESULTS: A total of 10,299 and 11,392 sit-to-stand and stand-to-sit transitions were recorded in healthy volunteers and stroke survivors, respectively. Healthy volunteers had significantly higher overall mean peak velocities for both transitions compared with stroke survivors [70.7°/s ± 52.2 versus 44.2°/s ± 28.0 for sit-to-stand, P < 0.001 and 74.7°/s ± 51.8 versus 46.0°/s ± 31.9 for stand-to-sit; P < 0.001]. Mean peak velocity of transition was associated with increased variation in peak velocity across both groups. CONCLUSION: There were significant differences in the mean peak velocity of sit-to-stand and stand-to-sit transitions between the groups. Variation in an individual's mean peak velocity may be associated with the ability to perform these transitions. This method could be used to evaluate the effectiveness of interventions following injury such as stroke, as well as monitor decline in functional ability.


Assuntos
Acelerometria/métodos , Atividade Motora/fisiologia , Acidente Vascular Cerebral/fisiopatologia , Coxa da Perna/fisiologia , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Estudos de Casos e Controles , Feminino , Monitores de Aptidão Física , Humanos , Masculino , Pessoa de Meia-Idade , Postura/fisiologia , Posição Ortostática
20.
Int J Sports Med ; 40(10): 670-677, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31342477

RESUMO

Apoptosis-associated, speck-like protein containing a caspase recruitment domain (ASC) plays an important role in inflammatory cytokine synthesis in peripheral blood mononuclear cells (PBMCs), and the expression of ASC is suppressed by increased methylation of its CpG sites. The current study investigated the longitudinal association of replacing sedentary time with light-intensity physical activity (LPA) or moderate to vigorous-intensity physical activity (MVPA) on the ASC methylation in middle-aged people. We investigated 1 238 individuals who participated in baseline and 5-year follow-up surveys of a population-based cohort study. Sedentary, LPA and MVPA time were objectively measured using accelerometers. ASC methylation in PBMCs was measured by pyrosequencing. Using a multiple linear regression and employing an isotemporal substitution model, the longitudinal associations of changes in the sedentary time, LPA and MVPA on the changes in the ASC methylation were analyzed after adjusting for potential confounders. Substituting 60 min per day of LPA for sedentary time was associated with 1.17 times (95% confidence interval 1.07, 1.27) higher ASC methylation levels (mean of 7 CpG sites, P<0.001). However, such effects were not seen for MVPA. These results suggest that substituting LPA for sedentary time may be linked with increased (favorable) ASC methylation as a potential biomarker of systemic inflammation.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/química , Metilação de DNA , Exercício , Acelerometria , Idoso , Antropometria , Estudos de Coortes , Ilhas de CpG , Citocinas/sangue , Feminino , Monitores de Aptidão Física , Humanos , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Comportamento Sedentário
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA