Download or read book Predictive Modeling for Physical Activity Intensity Levels Using Data from Accelerometer Placed on the Wrist written by Christopher Owusu Yirenkyi and published by . This book was released on 2019 with total page 63 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Predicting Activity Type from Accelerometer Data written by Yonglei Zheng and published by . This book was released on 2012 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of physical activity is important in improving people's health as it can help people understand the relationship between physical activity and health. Accelerometers, due to its small size, low cost, convenience and its ability to provide objective information about the frequency, intensity, and duration of physical activity, has become the method of choice in measuring physical activity. Machine learning algorithms based on the featurized representation of accelerometer data have become the most widely used approaches in physical activity prediction. To improve the classification accuracy, this thesis first explored the impact of the choice of data (raw vs processed) as well as the choice of features on the performance of various classifiers. The empirical results showed that the machine learning algorithms with strong regularization capabilities always performed better if provided with the most comprehensive feature set extracted from raw accelerometer signal. Based on the hypothesis that for some time series, the most discriminative information could be found at subwindows of various sizes, the Subwindow Ensemble Model (SWEM) was proposed. The SWEM was designed for the accelerometer-based physical activity data, and classified the time series based on the features extracted from subwindows. It was evaluated on six time series datasets. Three of them were accelerometer-based physical activity data, which the SWEM was designed for, and the rest were different types of time series data chosen from other domains. The empirical results indicated a strong advantage of the SWEM over baseline models on the accelerometerbased physical activity data. Further analysis confirmed the hypothesis that the most discriminative features could be extracted from subwindows of different sizes, and they were effectively used by the SWEM.
Download or read book Physical Activity Assessments for Health related Research written by Greg Welk and published by Human Kinetics. This book was released on 2002 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: And examples -- References -- Construct validity in physical activity research / Matthew T. Mahar and David A. Rowe -- Definitional stage -- Confirmatory stage -- Theory-testing stage -- Summary -- References -- Physical activity data : odd distributions yield strange answers / Jerry R. Thomas and Katherine T. Thomas -- Overview of the general linear model and rank-order procedures -- Determining whether data are normally distributed -- Application of rank-order procedures -- Data distributions and correlation -- Extensions of GLM rank-order statistical procedures -- Summary -- Endnote -- References -- Equating and linking of physical activity questionnaires / Weimo Zhu -- What is scale equating? -- Equating methods -- Practical issues of scale equating -- Remaining challenges and future research directions -- Summary -- References.
Download or read book Associations of Total Activity Counts and Physical Activity Intensity Levels with the Metabolic Syndrome written by Dana Lizbeth Wolff and published by . This book was released on 2014 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: To clarify the protective benefits of physical activity (PA), epidemiologists and public health researchers continue to seek improved methods of assessing PA. In particular, accelerometers have gained acceptance with researchers as they provide reliable estimates of PA and can record both the amount and intensity of ambulatory movement. However, there is concern that accelerometer data reduction techniques may not provide quantitatively accurate measurements of time spent in various PA intensity categories. One way to circumvent these inaccuracies is to use the accelerometer-derived total activity counts (TAC), which is a more direct expression of what the monitor records. In order to explore the efficacy of TAC as a measure of PA, this dissertation used data from the 2003 - 2006 National Health and Nutrition Examination Survey to: 1) investigate whether TAC was more strongly associated with cardiometabolic biomarkers than minutes of moderate-to-vigorous PA (MVPA), 2) determine population-referenced TAC percentiles for the U.S. population, and 3) determine which accelerometer-derived measure(s) of PA intensity and volume provided the best fit for assessing the association with the metabolic syndrome. The first study demonstrated that TAC had stronger associations with cardiometabolic biomarkers than time spent in MVPA bouts of ≥ 10 minutes, suggesting TAC is a more robust measure of PA (Part IV). In the second study, age- and gender- specific population-referenced percentiles for TAC, MVPA, and light PA (LPA) were developed (Part V). This is a different approach to accelerometer data reduction that complements the current method of looking at time spent in intensity sub-categories. The third study used structural equation modeling to examine whether TAC, MVPA, or MVPA plus LPA provided the best fit for assessing the relationship with the metabolic syndrome (Part VI). This study also assessed the relative contribution of LPA, MPA, VPA, and TAC to the reduction in the prevalence of the metabolic syndrome. Results indicated a model with TAC provided the best fit for assessing the relationship between PA and the metabolic syndrome. These findings suggest TAC, may be a better measure of PA when examining the reduction in the metabolic syndrome prevalence.
Download or read book Recursive Forecasting and Ordinal Statistical Models from Accelerometer Data written by Fatimah Alawad and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accelerometers are devices that measure acceleration along x-, y- and z-axes. These devices can be worn and used to predict activity intensity. The accuracy of conventional accelerometer analysis methods is sub-optimal but newer, more advanced methods that use raw data from the accelerometer for the prediction of activity intensity have been developed. As responses are correlated sequentially and collected over time, time-series methods can be considered to improve prediction accuracy. Prior responses, however, are not available at the testing stage or in practice. However, in testing, prior predictions can be used as in place of lagging responses on models which were built to use lagging responses as observations. This approach is known as recursive forecasting and applying it to accelerometer data is a unique approach in the literature. In addition, until recently, decision models for accelerometer data did not take into account the ordinality of the responses (for example, sedentary, moderate, and vigorous). This is significant information that we consider in this thesis. In this research, we develop more accurate decision models for predicting activity intensity from accelerometer data by using recursive forecasting. We also consider ordinal statistical models. Measuring activity intensity objectively is a crucial consideration in physiology and exercise science and these methods can be implemented in these disciplines to improve such measurement.
Download or read book The Objective Monitoring of Physical Activity Contributions of Accelerometry to Epidemiology Exercise Science and Rehabilitation written by Roy J. Shephard and published by Springer. This book was released on 2016-08-02 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book examines the new knowledge that has been gained from the objective monitoring of habitual physical activity by means of pedometers and accelerometers. It reviews current advances in the technology of activity monitoring and details advantages of objective monitors relative to physical activity questionnaires. It points to continuing gaps in knowledge, and explores the potential for further advances in the design of objective monitoring devices. Epidemiologists have studied relationships between questionnaire assessments of habitual physical activity and various medical conditions for some seventy years. In general, they have observed positive associations between regular exercise and good health, but because of inherent limitations in the reliability and accuracy of physical activity questionnaires, optimal exercise recommendations for the prevention and treatment of disease have remained unclear. Inexpensive pedometers and accelerometers now offer the epidemiologist the potential to collect relatively precisely graded and objective information on the volume, intensity and patterns of effort that people are undertaking, to relate this data to past and future health experience, and to establish dose/response relationships between physical activity and the various components of health. Such information is important both in assessing the causal nature of the observed associations and in establishing evidence-based recommendations concerning the minimal levels of daily physical activity needed to maintain good health.
Download or read book Statistical Modeling of Physical Activity Based on Accelerometer Data written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sedentary Behavior and Health written by Weimo Zhu and published by Human Kinetics. This book was released on 2017-03-03 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: From office jobs and long commutes to passive entertainment like television and video games, humans are sitting more than ever. Though lack of exercise has major health consequences, researchers are now examining the additional and widespread health risk of the simple act of sitting for extended periods. With research from leading scientists, Sedentary Behavior and Health: Concepts, Assessments, and Interventions presents evidence on sedentary behavior, its apparent health risks, and suggestions on measuring and altering this behavior. The highly respected international author team provides an interdisciplinary review of current research, examining scientific, public health, and broader social questions about the implications of sedentary behavior. These topics include humans’ physiological predispositions, exacerbation of current health conditions like obesity and diabetes, and the design and ergonomics of offices and chairs. To examine the many facets of this developing area of study, Sedentary Behavior and Health is divided into five parts: • “Sedentary Behavior Concepts and Context” reviews the physiology of sedentary behavior, investigating current habits from the perspectives of evolution, industrial engineering, and design. • “Sedentary Behavior and Health” explores the relationship between sedentary behavior and several major chronic diseases, including obesity, cardiovascular disease, and low-back pain. • “Measuring and Analyzing Sedentary Behavior” explains research methods for understanding and measuring sedentary behavior in order to recognize patterns and design interventions. • “Sedentary Behavior and Subpopulations” covers issues, risks, and behaviors in groups such as children, working adults, older adults, and minorities. • “Changing Sedentary Behavior” provides methods and recommendations for improvement with environmental, social, community, worksite, and technology-based interventions. Included in this groundbreaking text are learning objectives, key concepts, and study questions to focus attention on key issues and reinforce concepts. Reviews of the literature in the field are presented, many with comparisons in table form, to provide the full scope of research. Sidebars throughout the text apply theoretical concepts to real-world scenarios. Inactivity is mismatched with many aspects of humans’ genetic makeup. While it is becoming the new norm, the consequences of this behavior are emerging as a public health threat. Sedentary Behavior and Health will serve as a key reference for the rapidly emerging research area of sedentary behavior.
Download or read book Physical Activity Epidemiology written by Rod K. Dishman and published by Human Kinetics. This book was released on 2012-08-29 with total page 1407 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physical Activity Epidemiology, Second Edition, provides a comprehensive discussion of current population-level studies showing the influence of physical activity on disease. Updated with extensive new research collected in the eight years since the previous edition, the second edition adds the expertise of respected epidemiologist I-Min Lee. To assist readers in understanding the public health significance of physical activity, Dishman, Heath, and Lee present a detailed review of research findings and what those findings suggest regarding the relationship between physical activity and a variety of health risks. The second edition of this groundbreaking text has been exhaustively updated to reflect the wealth of new research published in this fast-moving field of study. With more than 100 pages of additional content, the text also offers more detailed coverage of all-cause and coronary heart disease mortality, expanded coverage of pathophysiology and biological plausibility, new information on physical activity among various racial–ethnic populations, and the effects of physical activity on cognitive function, dementia, and HIV/AIDS. More than 250 tables and figures, twice the number found in the previous edition, highlight the latest epidemiological information in an easy-to-understand visual format. Physical Activity Epidemiology, Second Edition, assists readers in understanding how leisure-time physical activity can enhance people’s quantity and quality of life by summarizing the available knowledge, detailing the methods used to obtain it, considering its implications for public health, and outlining the important questions that remain. Readers will find comprehensive discussion of these topics: • Evidence that physical activity protects against the development of coronary heart disease and stroke and premature death from all causes • Population-based studies and clinical experiments providing evidence that physical activity and exercise play a role in the primary and secondary prevention of mild hypertension, dyslipidemia, and obesity • Contemporary epidemiologic evidence that physical activity reduces the risk of type 2 diabetes and osteoporosis and protects against the development of breast and colon cancers, some inflammatory diseases, depression, and anxiety disorders • Considerations in the promotion of a safe, physically active lifestyle among all segments of the population Physical Activity Epidemiology, Second Edition, will engage and challenge students by examining the state of current research in all of its variation and even ambiguity. The text details the methodology and findings of classic and contemporary studies and then helps students begin to analyze the results. Special Strength of the Evidence sections found at the end of most chapters summarize the findings to determine the extent to which correlation and causation can be proven. Chapter objectives, chapter summaries, and sidebars in each chapter assist students in focusing on the key points of study, and an extensive glossary with detailed definitions provides a handy reference for review. Instructors will find a new image bank in this edition to enhance their class lecture materials. Physical Activity Epidemiology, Second Edition, offers students, sport and exercise scientists, health and fitness professionals, and public health administrators a comprehensive presentation of significant studies, how these studies contribute to understanding the relationship between activity and disease prevention, and how this information can be used in leading individuals, communities, and global society toward increased health and longevity.
Download or read book Oxford Textbook of Children s Sport and Exercise Medicine written by Neil Armstrong and published by Oxford University Press. This book was released on 2023 with total page 785 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 4th edition of the Oxford Textbook of Children's Sport and Exercise Medicine is the definitive single-volume reference in the field presented in four sections Exercise Science; Exercise Medicine; Sport Science; and Sport Medicine.
Download or read book A Comprehensive Validation of Activity Trackers for Estimating Physical Activity and Sedentary Behavior in Free living Settings written by Albert R. Mendoza and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of study one of this dissertation was to compare consumer activity trackers (ATs) with the research-grade ActiGraphTM GT3X-BT accelerometer (AG) in estimating energy expenditure (EE) and steps during orbital shaking at different frequencies. To address this aim, we utilized an electronic orbital shaking protocol (twenty-four, 3-minute trials; 2-hour trials). For all comparisons, the AG served as the reference measure. In the 3-min protocol, we showed that on average, the NL-1000 pedometer (NL) produced the lowest error (-9 steps/3-min) at 0.9 Hz (corresponding to moderate intensity). The magnitude of the error for the NL was 14 steps/3-min at a 3.0 Hz frequency (corresponding to very vigorous intensity). For the 2-hr protocol, estimates from all others were equivocal, with some overestimating steps (bias range: 1,331 steps/2-hrs for the Misfit Shine to 1,921 steps/2-hrs for the Misfit Flash [MFF]). For estimated EE bias ranged from26.6 kcals/2-hrs for the MFF to 45.8 kcals/2-hrs for the Misfit Shine. For other ATs, steps were underestimated (bias range: -5,770 steps/2-hrs for the Garmin Vivofit [GV] to -570 steps/2-hrs for the NL). For EE, the bias ranged from -436.8 kcals/2-hrs for the GV to -261.7 kcals/2-hrs for the Fitbit Flex [FBF]). This study provides evidence about the differences in prediction algorithms by device across a broad range of oscillation frequencies that corresponded to different PA intensity levels. For study two, we sought determine the accuracy and precision of activity trackers (ATs) in estimating steps, EE, activity minutes and sedentary time compared to direct observation (DO)-derived measures (criterion measures) in free-living settings. We also validated commonly used research-grade devices (e.g. hip-worn AG (AGhip), wrist-worn AG (AGwrist). Thirty-two healthy men and women (50% female, 37.5% minority; mean ± SD: Age = 32.3 ± 13.3 years; BMI = 24.4 ± 3.3 kg∙m-2) were directly observed while completing three, 2-hour visits on different days while wearing ten ATs, three research-grade devices and a biometric shirt. A validated DO system was used to derive criterion measures for activity and sedentary time (ST) outcomes. ATs were accurate with varying precision in estimating physical activity (PA) behaviors in free-living settings. Additionally, ATs and research-grade accelerometers performed similarly (e.g. more accurate in estimating steps and less accurate in estimating moderate-to-vigorous PA [MVPA] minutes). For all devices, step estimates were accurate and strongly correlated (r range: 0.91 for the Apple iWatch to 0.97 for the AGhip) with criterion measures but EE and MVPA estimates were less accurate and more variable (EE: r = 0.32 [GV] to r = 0.85 [AGhip]; MVPA: r = 0.2 [NL] to r = 0.75 [AGhip]). For ATs, estimates of sedentary time were the least accurate and weakly correlated (r=0.06 Fitbit One [FBO] and FBF) with criterion measures derived from DO. Implications from this study are that consumers and the research community using ATs such as Fitbit (FB) to track steps can be confident in estimating steps but less confident in estimating sedentary time. This study advances our understanding of the performance characteristics of ATs in free-living natural settings using a validated DO method to derive PA and ST measures. This work significantly advances the field of activity monitor validation that should set the standard for future work. The aims of study three were: 1) to examine the ability of ATs to detect change in PA and ST in free-living settings and 2) to examine the ability of research-grade accelerometers to detect change in PA and ST in free-living settings. To address these aims, we used an innovative approach to analyze data from study two. We defined change as a visit-to-visit difference that was greater than the within-subject standard deviation of the criterion measure (estimated by a linear-mixed model). Confusion matrices were used to examine percent agreement between DO visit-to-visit change and device visit-to-visit change. Key findings were focused on the widely used FBO and FBF and research-grade devices. We showed that, there was similar agreement between the hip-worn FBO and FBF with AGhip and AGwrist in estimates of change in steps (89.1% FBO, 88.8% FBF and 88.3% AGwrist, 91.4% AGhip correct classification), EE (73.4% FBO, 70.6% FBF and 77.0% AGhip correct classification) and MVPA minutes (accept FBF) (79.7% FBO, 65.2% FBF and 71.2% AGwrist, 77.0% AGhip correct classification) with criterion measured change. However, change in ST was more difficult to detect for the FB and AGhip (46.8% FBO, 42.3% FBF, 53.1% AGhip and 72.7% AGwrist correct classification). This novel study provides evidence that as an alternative to research-grade accelerometers, researchers may employ FB to measure step accumulation pre- and post-intervention and have a satisfactory level of confidence in FB change detection. This work significantly advances the field of activity monitor validation research and informs intervention practices that should set the standard for future work. This body of work provides the first comprehensive validation of ATs from highly controlled orbital shaker testing to directly-observed free-living settings. This translational research which has broad applications for using ATs for surveillance and intervention research and by the consumer.
Download or read book Routledge Handbook of Physical Activity Policy and Practice written by Joe Piggin and published by Routledge. This book was released on 2017-12-22 with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt: Physical activity, inactivity and their relationship to health are serious concerns for governments around the world. This is the first book to critically examine the policy and practice of physical activity from a multi-disciplinary, social-scientific perspective. Moving beyond the usual biophysical and epidemiological approaches, it defines and explores the key themes that are shaping the global physical activity debate. Unrivalled in its scale and scope, it presents the latest data on physical activity from around the world, including case studies from Europe, North and South America, Africa and Asia. Drawing on social, economic and behavioural sciences, it covers contexts from the global to the local and introduces the dominant ideas which inform the study of physical activity. Its 41 chapters examine the use of different forms of evidence in policymaking, the role of organisations in advocating physical activity, and the practical realities of public health interventions. The Routledge Handbook of Physical Activity Policy and Practice is a landmark publication for all students, academics, policymakers and practitioners interested in the social-scientific study of sport, exercise, physical activity and public health.
Download or read book WHO guidelines on physical activity and sedentary behaviour written by and published by World Health Organization. This book was released on 2020-11-20 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Encyclopedia of Sports Medicine written by Lyle J. Micheli and published by SAGE. This book was released on 2011 with total page 1881 pages. Available in PDF, EPUB and Kindle. Book excerpt: This encyclopedia presents state-of-the-art research and evidence-based applications on the topic of sports medicine.
Download or read book Classification Accuracy of the Wrist worn GENA Accelerometer During Structured Activity Bouts written by Whitney Allegra Welch and published by . This book was released on 2012 with total page 71 pages. Available in PDF, EPUB and Kindle. Book excerpt: Purpose: The purpose of this study is to determine whether the left wrist cutpoints of Esliger et al., for the triaxial GENEA accelerometer, are accurate for predicting intensity categories during 14 different activities including; treadmill-based, home and office, and sport activities. Methods: 130 adults wore a GENEA accelerometer on their left wrist while performing various lifestyle activities. The Oxycon Mobile Portable Metabolic Unit was used to measure oxygen uptake during each activity. Statistical analysis used Spearman's rank correlations to determine the relationship between measured and estimated intensity classifications. Cross tabulation tables were constructed to describe under or over estimation of misclassified activities, and one-way chi-squares were used to test whether the accuracy rate of each activity differed from 80%. Results: For all activities the GENEA accelerometerbased physical activity monitor explained 41.1% of the energy expenditure. The GENEA correctly classified 52.8% of observations when all activities were combined. Five of the 14 activities showed no statistical difference in physical activity intensity classification estimation when compared to 80% accuracy, with 1 activity (treadmill jogging at 9.6 km·hr−1 with 0% grade) showing statistically greater accuracy than 80%. For the remainder of the activities, the GENEA showed less than 80% accuracy for predicting intensity. Conclusion: Cross-validation of the proposed GENEA left wrist cutpoints classified the majority of activities performed significantly below the accuracy rate of 80%. Researchers should be cautious when applying the Esliger et al. cutpoints to a different population and activities not tested by those investigators.
Download or read book Statistical Modeling of Physical Activity Based on Accelerometer Data written by Norman Wirsik and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Children s Exercise Physiology written by Filipe Manuel Clemente and published by Frontiers Media SA. This book was released on 2020-06-22 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt:
