{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T02:30:37Z","timestamp":1777602637551,"version":"3.51.4"},"reference-count":112,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,7]],"date-time":"2022-01-07T00:00:00Z","timestamp":1641513600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000006","name":"Office of Naval Research","doi-asserted-by":"publisher","award":["N00014-21-1-203"],"award-info":[{"award-number":["N00014-21-1-203"]}],"id":[{"id":"10.13039\/100000006","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000006","name":"Office of Naval Research","doi-asserted-by":"publisher","award":["N000141812579"],"award-info":[{"award-number":["N000141812579"]}],"id":[{"id":"10.13039\/100000006","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Hypovolemia is a physiological state of reduced blood volume that can exist as either (1) absolute hypovolemia because of a lower circulating blood (plasma) volume for a given vascular space (dehydration, hemorrhage) or (2) relative hypovolemia resulting from an expanded vascular space (vasodilation) for a given circulating blood volume (e.g., heat stress, hypoxia, sepsis). This paper examines the physiology of hypovolemia and its association with health and performance problems common to occupational, military and sports medicine. We discuss the maturation of individual-specific compensatory reserve or decompensation measures for future wearable sensor systems to effectively manage these hypovolemia problems. The paper then presents areas of future work to allow such technologies to translate from lab settings to use as decision aids for managing hypovolemia. We envision a future that incorporates elements of the compensatory reserve measure with advances in sensing technology and multiple modalities of cardiovascular sensing, additional contextual measures, and advanced noise reduction algorithms into a fully wearable system, creating a robust and physiologically sound approach to manage physical work, fatigue, safety and health issues associated with hypovolemia for workers, warfighters and athletes in austere conditions.<\/jats:p>","DOI":"10.3390\/s22020442","type":"journal-article","created":{"date-parts":[[2022,1,9]],"date-time":"2022-01-09T23:08:26Z","timestamp":1641769706000},"page":"442","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Wearable Sensors and Machine Learning for Hypovolemia Problems in Occupational, Military and Sports Medicine: Physiological Basis, Hardware and Algorithms"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3241-6823","authenticated-orcid":false,"given":"Jacob P.","family":"Kimball","sequence":"first","affiliation":[{"name":"School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7952-1794","authenticated-orcid":false,"given":"Omer T.","family":"Inan","sequence":"additional","affiliation":[{"name":"School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9246-0554","authenticated-orcid":false,"given":"Victor A.","family":"Convertino","sequence":"additional","affiliation":[{"name":"Battlefield Health & Trauma Center for Human Integrative Physiology, US Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX 78234, USA"}]},{"given":"Sylvain","family":"Cardin","sequence":"additional","affiliation":[{"name":"Naval Medical Research Unit, JBSA Fort Sam Houston, San Antonio, TX 78234, USA"}]},{"given":"Michael N.","family":"Sawka","sequence":"additional","affiliation":[{"name":"School of Biological Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S51","DOI":"10.1007\/s40279-015-0395-7","article-title":"Hypohydration and Human Performance: Impact of Environment and Physiological Mechanisms","volume":"45","author":"Sawka","year":"2015","journal-title":"Sports Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e13805","DOI":"10.14814\/phy2.13805","article-title":"Exercise-heat stress with and without water replacement alters brain structures and impairs visuomotor performance","volume":"6","author":"Wittbrodt","year":"2018","journal-title":"Physiol. Rep."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1792","DOI":"10.1152\/japplphysiol.00517.2010","article-title":"Effect of hypohydration and altitude exposure on aerobic exercise performance and acute mountain sickness","volume":"109","author":"Castellani","year":"2010","journal-title":"J. Appl. Physiol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"368","DOI":"10.1152\/jappl.1992.73.1.368","article-title":"Human Tolerance to Heat Strain During Exercise\u2014Influence of Hydration","volume":"73","author":"Sawka","year":"1992","journal-title":"J. Appl. Physiol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1744","DOI":"10.1152\/japplphysiol.00200.2006","article-title":"Hypohydration and prior heat stress exacerbates decreases in cerebral blood flow velocity during standing","volume":"101","author":"Carter","year":"2006","journal-title":"J. Appl. Physiol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"597S","DOI":"10.1080\/07315724.2007.10719665","article-title":"Hydration at the work site","volume":"26","author":"Kenefick","year":"2007","journal-title":"J. Am. Coll. Nutr."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1531","DOI":"10.1002\/cphy.c200016","article-title":"Physiology of Human Hemorrhage and Compensation","volume":"11","author":"Convertino","year":"2021","journal-title":"Compr. Physiol."},{"key":"ref_8","first-page":"503","article-title":"Water","volume":"Volume 1","author":"Marriott","year":"2020","journal-title":"Present Knowledge in Nutrition: Basic Nutrition and Metabolism"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"432","DOI":"10.1152\/japplphysiol.00353.2017","article-title":"Wearable physiological monitoring for human thermal-work strain optimization","volume":"124","author":"Buller","year":"2018","journal-title":"J. Appl. Physiol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1701","DOI":"10.1007\/s00421-021-04642-3","article-title":"The physiological strain index does not reliably identify individuals at risk of reaching a thermal tolerance limit","volume":"121","author":"Davey","year":"2021","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"860","DOI":"10.1093\/milmed\/165.11.860","article-title":"Ambulatory physiological status monitoring during a mountaineering expedition","volume":"165","author":"Sonna","year":"2000","journal-title":"Mil. Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"3351","DOI":"10.1109\/JBHI.2021.3068619","article-title":"Unifying the Estimation of Blood Volume Decompensation Status in a Porcine Mode of Relative and Absolute Hypovolemia Via Wearable Sensing","volume":"25","author":"Kimball","year":"2021","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"442","DOI":"10.1152\/japplphysiol.00264.2017","article-title":"Wearable technology for compensatory reserve to sense hypovolemia","volume":"124","author":"Convertino","year":"2018","journal-title":"J. Appl. Physiol."},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Convertino, V.A., Schauer, S.G., Weitzel, E.K., Cardin, S., Stackle, M.E., Talley, M.J., Sawka, M.N., and Inan, O.T. (2020). Wearable Sensors Incorporating Compensatory Reserve Measurement for Advancing Physiological Monitoring in Critically Injured Trauma Patients. Sensors, 20.","DOI":"10.3390\/s20226413"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"690","DOI":"10.1177\/1535370219846425","article-title":"Physiological comparison of hemorrhagic shock and VO(2)max: A conceptual framework for defining the limitation of oxygen delivery","volume":"244","author":"Convertino","year":"2019","journal-title":"Exp. Biol. Med."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"455","DOI":"10.3945\/ajcn.112.044172","article-title":"Physiologic basis for understanding quantitative dehydration assessment","volume":"97","author":"Cheuvront","year":"2013","journal-title":"Am. J. Clin. Nutr."},{"key":"ref_17","first-page":"215","article-title":"Human vascular fluid responses to cold stress are not altered by cold acclimation","volume":"14","author":"Young","year":"1987","journal-title":"Undersea Biomed. Res."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"R265","DOI":"10.1152\/ajpregu.00225.2016","article-title":"Quantitative model of hematologic and plasma volume responses after ascent and acclimation to moderate to high altitudes","volume":"312","author":"Beidleman","year":"2017","journal-title":"Am. J. Physiol. Regul. Integr. Comp. Physiol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1705","DOI":"10.1002\/cphy.c140018","article-title":"Human Physiology in an Aquatic Environment","volume":"5","author":"Pendergast","year":"2015","journal-title":"Compr. Physiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1883","DOI":"10.1002\/cphy.c100082","article-title":"Integrated Physiological Mechanisms of Exercise Performance, Adaptation, and Maladaptation to Heat Stress","volume":"1","author":"Sawka","year":"2011","journal-title":"Compr. Physiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"407","DOI":"10.1111\/j.1748-1716.2010.02119.x","article-title":"Cardiovascular function in the heat-stressed human","volume":"199","author":"Crandall","year":"2010","journal-title":"Acta Physiol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1152\/japplphysiol.00415.2014","article-title":"Impact of skin temperature and hydration on plasma volume responses during exercise","volume":"117","author":"Kenefick","year":"2014","journal-title":"J. Appl. Physiol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1055\/s-2007-971887","article-title":"Thermal and cardiovascular strain from hypohydration: Influence of exercise intensity","volume":"19","author":"Montain","year":"1998","journal-title":"Int. J. Sports Med."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"657","DOI":"10.1002\/cphy.c130012","article-title":"Performance in the Heat-Physiological Factors of Importance for Hyperthermia-Induced Fatigue","volume":"4","author":"Nybo","year":"2014","journal-title":"Compr. Physiol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1016\/j.autneu.2016.02.002","article-title":"Cardiovascular adaptations supporting human exercise-heat acclimation","volume":"196","author":"Periard","year":"2016","journal-title":"Auton. Neurosci. Basic Clin."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"128","DOI":"10.1152\/physrev.1956.36.1.128","article-title":"Responses of Body Fluid Compartments to Heat and Cold","volume":"36","author":"Bass","year":"1956","journal-title":"Physiol. Rev."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"657","DOI":"10.1152\/jappl.1980.48.4.657","article-title":"Role of Thermal and Exercise Factors in the Mechanism of Hypervolemia","volume":"48","author":"Convertino","year":"1980","journal-title":"J. Appl. Physiol."},{"key":"ref_28","first-page":"167","article-title":"Influence of body water and blood volume on thermoregulation and exercise performance in the heat","volume":"27","author":"Sawka","year":"1999","journal-title":"Exerc. Sport Sci. Rev."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1379","DOI":"10.3389\/fphys.2019.01379","article-title":"Hematological Adaptations to Prolonged Heat Acclimation in Endurance-Trained Males","volume":"10","author":"Oberholzer","year":"2019","journal-title":"Front. Physiol."},{"key":"ref_30","first-page":"265","article-title":"Acute Polycythemia and Human-Performance during Exercise and Exposure to Extreme Environments","volume":"17","author":"Sawka","year":"1989","journal-title":"Exerc. Sport Sci. Rev. Ser."},{"key":"ref_31","unstructured":"Buskirk, E.R., and Puhl, S.M. (1996). Environmental Influences on Body Fluid Balance During Exercise: Altitude. Body Fluid Balance: Exercise and Sport, CRC Press."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"636","DOI":"10.1152\/jappl.1996.81.2.636","article-title":"Altitude acclimatization and blood volume: Effects of exogenous erythrocyte volume expansion","volume":"81","author":"Sawka","year":"1996","journal-title":"J. Appl. Physiol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e14051","DOI":"10.14814\/phy2.14051","article-title":"Variability in human plasma volume responses during high-altitude sojourn","volume":"7","author":"Young","year":"2019","journal-title":"Physiol. Rep."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"436","DOI":"10.1152\/japplphysiol.01176.2012","article-title":"Sweat rate and prediction validation during high-altitude treks on Mount Kilimanjaro","volume":"114","author":"Gonzalez","year":"2013","journal-title":"J. Appl. Physiol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"608","DOI":"10.1152\/japplphysiol.01443.2006","article-title":"Systemic hypoxia causes cutaneous vasodilation in healthy humans","volume":"103","author":"Simmons","year":"2007","journal-title":"J. Appl. Physiol."},{"key":"ref_36","unstructured":"Buskirk, E.R., and Puhl, S.M. (1996). Environmental Influences on Body Fluid Balance during Exercise: Cold Exposure. Body Fluid Balance: Exercise and Sport, CRC Press."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1202","DOI":"10.1113\/EP087718","article-title":"Cold-induced cutaneous vasoconstriction in humans: Function, dysfunction and the distinctly counterproductive","volume":"104","author":"Alba","year":"2019","journal-title":"Exp. Physiol."},{"key":"ref_38","first-page":"1","article-title":"Cardiovascular Adaptations to Exercise Training","volume":"6","author":"Hellsten","year":"2016","journal-title":"Compr. Physiol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"72","DOI":"10.1097\/MAJ.0b013e318063c6e4","article-title":"Blood volume response to physical activity and inactivity","volume":"334","author":"Convertino","year":"2007","journal-title":"Am. J. Med. Sci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"332","DOI":"10.1097\/00005768-200002000-00012","article-title":"Blood volume: Importance and adaptations to exercise training, environmental stresses, and trauma\/sickness","volume":"32","author":"Sawka","year":"2000","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"302","DOI":"10.2165\/00007256-198908050-00004","article-title":"The Effect of Detraining and Reduced Training on the Physiological Adaptations to Aerobic ExerciseTraining","volume":"8","author":"Neufer","year":"1989","journal-title":"Sports Med."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"697","DOI":"10.1152\/japplphysiol.00965.2017","article-title":"Cardiovascular responses to exercise when increasing skin temperature with narrowing of the core-to-skin temperature gradient","volume":"125","author":"Chou","year":"2018","journal-title":"J. Appl. Physiol."},{"key":"ref_43","first-page":"1","article-title":"The Physiology of Static Exercise","volume":"14","author":"Petrofsky","year":"1986","journal-title":"Exerc. Sport Sci. Rev. Ser."},{"key":"ref_44","first-page":"175","article-title":"Physiology of Upper-Body Exercise","volume":"14","author":"Sawka","year":"1986","journal-title":"Exerc. Sport Sci. Rev. Ser."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"711","DOI":"10.1161\/01.RES.24.5.711","article-title":"Human Cardiovascular Adjustments to Rapid Changes in Skin Temperature During Exercise","volume":"24","author":"Rowell","year":"1969","journal-title":"Circ. Res."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"e14433","DOI":"10.14814\/phy2.14433","article-title":"Dehydration reduces stroke volume and cardiac output during exercise because of impaired cardiac filling and venous return, not left ventricular function","volume":"8","author":"Watanabe","year":"2020","journal-title":"Physiol. Rep."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"2232","DOI":"10.1152\/jn.00403.2017","article-title":"Sympathetic neural and hemodynamic responses to head-up tilt during isoosmotic and hyperosmotic hypovolemia","volume":"118","author":"Posch","year":"2017","journal-title":"J. Neurophysiol."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"874","DOI":"10.1177\/1535370217694099","article-title":"The physiology of blood loss and shock: New insights from a human laboratory model of hemorrhage","volume":"242","author":"Schiller","year":"2017","journal-title":"Exp. Biol. Med."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"R88","DOI":"10.1152\/ajpregu.00235.2018","article-title":"Impact of environmental stressors on tolerance to hemorrhage in humans","volume":"316","author":"Crandall","year":"2019","journal-title":"Am. J. Physiol.-Regul. Integr. Comp. Physiol."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1097\/SHK.0000000000000559","article-title":"The Compensatory Reserve for Early and Accurate Prediction of Hemodynamic Compromise: A Review of the Underlying Physiology","volume":"45","author":"Convertino","year":"2016","journal-title":"Shock"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"74","DOI":"10.1097\/SHK.0000000000000653","article-title":"The Effect of Passive Heat Stress and Exercise-Induced Dehydration on the Compensatory Reserve During Simulated Hemorrhage","volume":"46","author":"Gagnon","year":"2016","journal-title":"Shock"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"6","DOI":"10.55460\/SFRB-RGN9","article-title":"Compensatory Reserve for Early and Accurate Prediction of Hemodynamic Compromise: Case Studies for Clinical Utility in Acute Care and Physical Performance","volume":"16","author":"Stewart","year":"2016","journal-title":"J. Spec. Oper. Med."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"1009","DOI":"10.3357\/AMHP.5460.2019","article-title":"Exercise-Induced Changes in Compensatory Reserve and Heart Rate Complexity","volume":"90","author":"Mulder","year":"2019","journal-title":"Aerosp. Med. Hum. Perform."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"282","DOI":"10.3390\/electronics3020282","article-title":"Wearable Photoplethysmographic Sensors-Past and Present","volume":"3","author":"Tamura","year":"2014","journal-title":"Electronics"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1260\/2040-2295.5.4.429","article-title":"Effects of Skin Surface Temperature on Photoplethysmograph","volume":"5","author":"Jeong","year":"2014","journal-title":"J. Healthc. Eng."},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"Fine, J., Branan, K.L., Rodriguez, A.J., Boonya-ananta, T., Ramella-Roman, J.C., McShane, M.J., and Cote, G.L. (2021). Sources of Inaccuracy in Photoplethysmography for Continuous Cardiovascular Monitoring. Biosensors, 11.","DOI":"10.3390\/bios11040126"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"557","DOI":"10.1152\/japplphysiol.00367.2017","article-title":"Wearable physiological sensors and real-time algorithms for detection of acute mountain sickness","volume":"124","author":"Muza","year":"2018","journal-title":"J. Appl. Physiol."},{"key":"ref_58","doi-asserted-by":"crossref","unstructured":"Zia, J., Kimball, J., Rolfes, C., Hahn, J.O., and Inan, O.T. (2020). Enabling the assessment of trauma-induced hemorrhage via smart wearable systems. Sci. Adv., 6.","DOI":"10.1126\/sciadv.abb1708"},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"280","DOI":"10.1109\/TBCAS.2015.2405480","article-title":"A Wearable Patch to Enable Long-Term Monitoring of Environmental, Activity and Hemodynamics Variables","volume":"10","author":"Etemadi","year":"2016","journal-title":"IEEE Trans. Biomed. Circuits Syst."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"1926","DOI":"10.1109\/JBHI.2020.3021532","article-title":"Wearable Cuff-Less Blood Pressure Estimation at Home via Pulse Transit Time","volume":"25","author":"Ganti","year":"2021","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1161\/01.CIR.46.3.559","article-title":"Systolic Time Intervals as Measures of Contractile State of Left Ventricular Myocardium in Man","volume":"46","author":"Ahmed","year":"1972","journal-title":"Circulation"},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1161\/01.CIR.56.2.146","article-title":"Critical-Review of Systolic-Time Intervals","volume":"56","author":"Lewis","year":"1977","journal-title":"Circulation"},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1097\/SHK.0000000000000077","article-title":"Precordial Vibrations Provide Noninvasive Detection of Early-Stage Hemorrhage","volume":"41","author":"Tavakolian","year":"2014","journal-title":"Shock"},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"e004313","DOI":"10.1161\/CIRCHEARTFAILURE.117.004313","article-title":"Novel Wearable Seismocardiography and Machine Learning Algorithms Can Assess Clinical Status of Heart Failure Patients","volume":"11","author":"Inan","year":"2018","journal-title":"Circ. Heart Fail."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"948","DOI":"10.1016\/j.cardfail.2020.05.014","article-title":"Wearable Patch-Based Estimation of Oxygen Uptake and Assessment of Clinical Status during Cardiopulmonary Exercise Testing in Patients With Heart Failure","volume":"26","author":"Shandhi","year":"2020","journal-title":"J. Card. Fail."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"176","DOI":"10.1109\/TBME.2021.3090376","article-title":"Reducing the Impact of External Vibrations on Fiducial Point Detection in Seismocardiogram Signals","volume":"69","author":"Lin","year":"2022","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"1277","DOI":"10.1109\/TBME.2016.2600945","article-title":"Quantifying and Reducing Motion Artifacts in Wearable Seismocardiogram Measurements During Walking to Assess Left Ventricular Health","volume":"64","author":"Javaid","year":"2017","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_68","unstructured":"Vest, A.N., Poian, G.D., Li, Q., Liu, C., Nemati, S., Shah, A., and Clifford, G.D. (2019). Cliffordlab\/PhysioNet-Cardiovascular-Signal-Toolbox: PhysioNet-Cardiovascular-Signal-Toolbox 1.0.2. Zenodo."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"1080","DOI":"10.1109\/JBHI.2019.2931348","article-title":"A Unified Framework for Quality Indexing and Classification of Seismocardiogram Signals","volume":"24","author":"Zia","year":"2020","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"5702","DOI":"10.1109\/JSEN.2016.2573269","article-title":"Motion Artifact Cancellation of Seismocardiographic Recording From Moving Subjects","volume":"16","author":"Yang","year":"2016","journal-title":"IEEE Sens. J."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"1466","DOI":"10.1109\/JBHI.2017.2764798","article-title":"Combined Seismo- and Gyro-Cardiography: A More Comprehensive Evaluation of Heart-Induced Chest Vibrations","volume":"22","author":"Yang","year":"2018","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"2365","DOI":"10.1109\/JBHI.2019.2895775","article-title":"Performance Analysis of Gyroscope and Accelerometer Sensors for Seismocardiography-Based Wearable Pre-Ejection Period Estimation","volume":"23","author":"Shandhi","year":"2019","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"784","DOI":"10.1109\/TBME.2018.2856700","article-title":"An Independent Component Analysis Approach to Motion Noise Cancelation of Cardio-Mechanical Signals","volume":"66","author":"Yang","year":"2019","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"566","DOI":"10.1109\/TBME.2005.869784","article-title":"Motion artifact reduction in photoplethysmography using independent component analysis","volume":"53","author":"Kim","year":"2006","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"670","DOI":"10.1109\/JBHI.2013.2264358","article-title":"A Motion-Tolerant Adaptive Algorithm for Wearable Photoplethysmographic Biosensors","volume":"18","author":"Yousefi","year":"2014","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"522","DOI":"10.1109\/TBME.2014.2359372","article-title":"TROIKA: A General Framework for Heart Rate Monitoring Using Wrist-Type Photoplethysmographic Signals During Intensive Physical Exercise","volume":"62","author":"Zhang","year":"2015","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"50","DOI":"10.1016\/j.autneu.2013.04.005","article-title":"Wearable seismocardiography: Towards a beat-by-beat assessment of cardiac mechanics in ambulant subjects","volume":"178","author":"Vaini","year":"2013","journal-title":"Auton. Neurosci. Basic Clin."},{"key":"ref_78","doi-asserted-by":"crossref","unstructured":"An, X., and Stylios, G.K. (2020). Comparison of Motion Artefact Reduction Methods and the Implementation of Adaptive Motion Artefact Reduction in Wearable Electrocardiogram Monitoring. Sensors, 20.","DOI":"10.3390\/s20051468"},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"635","DOI":"10.1109\/JBHI.2016.2582340","article-title":"ECG Denoising Using Marginalized Particle Extended Kalman Filter With an Automatic Particle Weighting Strategy","volume":"21","author":"Hesar","year":"2017","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"1863","DOI":"10.1109\/TBME.2014.2309293","article-title":"Novel Electrodes for Underwater ECG Monitoring","volume":"61","author":"Reyes","year":"2014","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"2464","DOI":"10.1007\/s10439-015-1528-8","article-title":"Novel Conductive Carbon Black and Polydimethlysiloxane ECG Electrode: A Comparison with Commercial Electrodes in Fresh, Chlorinated, and Salt Water","volume":"44","author":"Noh","year":"2016","journal-title":"Ann. Biomed. Eng."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1016\/j.patrec.2018.02.010","article-title":"Deep learning for sensor-based activity recognition: A survey","volume":"119","author":"Wang","year":"2019","journal-title":"Pattern Recognit. Lett."},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"20398","DOI":"10.1109\/JSEN.2021.3095176","article-title":"AdaptNet: Human Activity Recognition via Bilateral Domain Adaptation Using Semi-Supervised Deep Translation Networks","volume":"21","author":"An","year":"2021","journal-title":"IEEE Sens. J."},{"key":"ref_84","doi-asserted-by":"crossref","first-page":"156","DOI":"10.1109\/TITB.2005.856864","article-title":"Implementation of a real-time human movement classifier using a triaxial accelerometer for ambulatory monitoring","volume":"10","author":"Karantonis","year":"2006","journal-title":"IEEE Trans. Inf. Technol. Biomed."},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"2656","DOI":"10.1109\/TBME.2011.2160723","article-title":"Identifying Types of Physical Activity With a Single Accelerometer: Evaluating Laboratory-trained Algorithms in Daily Life","volume":"58","author":"Gyllensten","year":"2011","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_86","doi-asserted-by":"crossref","first-page":"1770","DOI":"10.1249\/MSS.0b013e3181a24536","article-title":"Detection of Type, Duration, and Intensity of Physical Activity Using an Accelerometer","volume":"41","author":"Bonomi","year":"2009","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1186\/s13673-017-0097-2","article-title":"Feature extraction for robust physical activity recognition","volume":"7","author":"Zhu","year":"2017","journal-title":"Hum. Cent. Comput. Inf. Sci."},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/978-3-540-24646-6_1","article-title":"Activity Recognition from User-Annotated Acceleration Data","volume":"Volume 3001","author":"Ferscha","year":"2004","journal-title":"Pervasive Computing, Proceedings"},{"key":"ref_89","doi-asserted-by":"crossref","first-page":"194","DOI":"10.1016\/j.gaitpost.2006.09.012","article-title":"Evaluation of a threshold-based tri-axial accelerometer fall detection algorithm","volume":"26","author":"Bourke","year":"2007","journal-title":"Gait Posture"},{"key":"ref_90","doi-asserted-by":"crossref","first-page":"566","DOI":"10.1109\/TBME.2013.2284069","article-title":"Predicting Free-Living Energy Expenditure Using a Miniaturized Ear-Worn Sensor: An Evaluation Against Doubly Labeled Water","volume":"61","author":"Bouarfa","year":"2014","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_91","first-page":"1034","article-title":"Automatic classification of ambulatory movements and evaluation of energy consumptions utilizing accelerometers and a barometer","volume":"11","author":"Ohtaki","year":"2005","journal-title":"Microsyst. Technol.-Micro-Nanosyst. Inf. Storage Processing Syst."},{"key":"ref_92","doi-asserted-by":"crossref","first-page":"1339","DOI":"10.1109\/JBHI.2015.2432454","article-title":"Posture and Activity Recognition and Energy Expenditure Estimation in a Wearable Platform","volume":"19","author":"Sazonov","year":"2015","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"382","DOI":"10.3414\/ME13-02-0031","article-title":"Automatic Heart Rate Normalization for Accurate Energy Expenditure Estimation An Analysis of Activities of Daily Living and Heart Rate Features","volume":"53","author":"Altini","year":"2014","journal-title":"Methods Inf. Med."},{"key":"ref_94","doi-asserted-by":"crossref","first-page":"e13938","DOI":"10.2196\/13938","article-title":"Accuracy of 12 Wearable Devices for Estimating Physical Activity Energy Expenditure Using a Metabolic Chamber and the Doubly Labeled Water Method: Validation Study","volume":"7","author":"Murakami","year":"2019","journal-title":"JMIR Mhealth Uhealth"},{"key":"ref_95","doi-asserted-by":"crossref","first-page":"473","DOI":"10.1152\/japplphysiol.00299.2017","article-title":"Extracting aerobic system dynamics during unsupervised activities of daily living using wearable sensor machine learning models","volume":"124","author":"Beltrame","year":"2018","journal-title":"J. Appl. Physiol."},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"79","DOI":"10.1152\/japplphysiol.00135.2010","article-title":"Skin temperature modifies the impact of hypohydration on aerobic performance","volume":"109","author":"Kenefick","year":"2010","journal-title":"J. Appl. Physiol."},{"key":"ref_97","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1113\/expphysiol.2011.061002","article-title":"High skin temperature and hypohydration impair aerobic performance","volume":"97","author":"Sawka","year":"2012","journal-title":"Exp. Physiol."},{"key":"ref_98","unstructured":"Texas Instruments: Electrocardiogram (ECG) (2021, December 02). Electrocardiogram (ECG) Integrated Circuits and Reference Designs. Available online: https:\/\/www.ti.com\/solution\/electrocardiogram-ecg."},{"key":"ref_99","doi-asserted-by":"crossref","first-page":"1603","DOI":"10.1126\/science.1182383","article-title":"Materials and Mechanics for Stretchable Electronics","volume":"327","author":"Rogers","year":"2010","journal-title":"Science"},{"key":"ref_100","doi-asserted-by":"crossref","first-page":"1057","DOI":"10.3389\/fphys.2017.01057","article-title":"Support Vector Machine Based Monitoring of Cardio-Cerebrovascular Reserve during Simulated Hemorrhage","volume":"8","author":"Bennis","year":"2018","journal-title":"Front. Physiol."},{"key":"ref_101","doi-asserted-by":"crossref","unstructured":"Reljin, N., Zimmer, G., Malyuta, Y., Shelley, K., Mendelson, Y., Blehar, D.J., Darling, C.E., and Chon, K.H. (2018). Using support vector machines on photoplethysmographic signals to discriminate between hypovolemia and euvolemia. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0195087"},{"key":"ref_102","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s13054-016-1223-7","article-title":"Predicting cardiorespiratory instability","volume":"20","author":"Pinsky","year":"2016","journal-title":"Crit. Care"},{"key":"ref_103","doi-asserted-by":"crossref","first-page":"384","DOI":"10.1513\/AnnalsATS.201611-905OC","article-title":"Dynamic and Personalized Risk Forecast in Step-Down Units Implications for Monitoring Paradigms","volume":"14","author":"Chen","year":"2017","journal-title":"Ann. Am. Thorac. Soc."},{"key":"ref_104","first-page":"1841","article-title":"Modelling Risk of Cardio-Respiratory Instability as a Heterogeneous Process","volume":"2015","author":"Chen","year":"2015","journal-title":"AMIA Annu. Symp. Proc. AMIA Symp."},{"key":"ref_105","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s13054-020-03379-3","article-title":"Prediction of hypotension events with physiologic vital sign signatures in the intensive care unit","volume":"24","author":"Yoon","year":"2020","journal-title":"Crit. Care"},{"key":"ref_106","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1016\/0010-4825(86)90001-6","article-title":"Prediction Modeling of Physiological-Responses and Human-Performance in the Heat","volume":"16","author":"Pandolf","year":"1986","journal-title":"Comput. Biol. Med."},{"key":"ref_107","doi-asserted-by":"crossref","first-page":"502","DOI":"10.1093\/milmed\/164.7.502","article-title":"Fluid replacement recommendations for training in hot weather","volume":"164","author":"Montain","year":"1999","journal-title":"Mil. Med."},{"key":"ref_108","unstructured":"Jacklitsch, B., Williams, W.J., Musolin, K., Coca, A., Kim, J.-H., and Turner, N. (2016). NIOSH Criteria for a Recommended Standard: Occupational Exposure to Heat and Hot Environments, U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health."},{"key":"ref_109","unstructured":"(2003). Heat Stress Control and Heat Casualty Management, Headquarters, Department of Army and Air Force, Army Publishing Directorate. Technical Bulletin Medical 507\/AFPAM 48-152(I)."},{"key":"ref_110","doi-asserted-by":"crossref","first-page":"1989","DOI":"10.1152\/japplphysiol.00367.2010","article-title":"Mechanisms of aerobic performance impairment with heat stress and dehydration","volume":"109","author":"Cheuvront","year":"2010","journal-title":"J. Appl. Physiol."},{"key":"ref_111","doi-asserted-by":"crossref","first-page":"422","DOI":"10.1097\/00005768-200103000-00014","article-title":"Physiologic tolerance to uncompensable heat: Intermittent exercise, field vs laboratory","volume":"33","author":"Sawka","year":"2001","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_112","doi-asserted-by":"crossref","first-page":"1233","DOI":"10.1007\/s00421-021-04614-7","article-title":"Heat adaptation in humans with controlled heart rate heat acclimation","volume":"121","author":"Periard","year":"2021","journal-title":"Eur. J. Appl. Physiol."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/2\/442\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T14:01:37Z","timestamp":1760364097000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/2\/442"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,1,7]]},"references-count":112,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2022,1]]}},"alternative-id":["s22020442"],"URL":"https:\/\/doi.org\/10.3390\/s22020442","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,1,7]]}}}