{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T23:21:22Z","timestamp":1772320882215,"version":"3.50.1"},"reference-count":55,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2020,9,29]],"date-time":"2020-09-29T00:00:00Z","timestamp":1601337600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000024","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["396398"],"award-info":[{"award-number":["396398"]}],"id":[{"id":"10.13039\/501100000024","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["532806-2019"],"award-info":[{"award-number":["532806-2019"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001804","name":"Canada Research Chairs","doi-asserted-by":"publisher","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}],"id":[{"id":"10.13039\/501100001804","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Fatigue is a multifunctional and complex phenomenon that affects how individuals perform an activity. Fatigue during running causes changes in normal gait parameters and increases the risk of injury. To address this problem, wearable sensors have been proposed as an unobtrusive and portable system to measure changes in human movement as a result of fatigue. Recently, a category of wearable devices that has gained attention is flexible textile strain sensors because of their ability to be woven into garments to measure kinematics. This study uses flexible textile strain sensors to continuously monitor the kinematics during running and uses a machine learning approach to estimate the level of fatigue during running. Five female participants used the sensor-instrumented garment while running to a state of fatigue. In addition to the kinematic data from the flexible textile strain sensors, the perceived level of exertion was monitored for each participant as an indication of their actual fatigue level. A stacked random forest machine learning model was used to estimate the perceived exertion levels from the kinematic data. The machine learning algorithm obtained a root mean squared value of 0.06 and a coefficient of determination of 0.96 in participant-specific scenarios. This study highlights the potential of flexible textile strain sensors to objectively estimate the level of fatigue during running by detecting slight perturbations in lower extremity kinematics. Future iterations of this technology may lead to real-time biofeedback applications that could reduce the risk of running-related overuse injuries.<\/jats:p>","DOI":"10.3390\/s20195573","type":"journal-article","created":{"date-parts":[[2020,9,29]],"date-time":"2020-09-29T08:43:27Z","timestamp":1601369007000},"page":"5573","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Fatigue Monitoring in Running Using Flexible Textile Wearable Sensors"],"prefix":"10.3390","volume":"20","author":[{"given":"Mohsen","family":"Gholami","sequence":"first","affiliation":[{"name":"Menrva Research Group, Schools of Mechatronic Systems &amp; Engineering Science, Simon Fraser University, Metro Vancouver, BC V5A 1S6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1454-3546","authenticated-orcid":false,"given":"Christopher","family":"Napier","sequence":"additional","affiliation":[{"name":"Menrva Research Group, Schools of Mechatronic Systems &amp; Engineering Science, Simon Fraser University, Metro Vancouver, BC V5A 1S6, Canada"},{"name":"Department of Physical Therapy, Faculty of Medicine, University of British Columbia, Vancouver, BC V5T 1Z3, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Astrid Garc\u00eda","family":"Pati\u00f1o","sequence":"additional","affiliation":[{"name":"Menrva Research Group, Schools of Mechatronic Systems &amp; Engineering Science, Simon Fraser University, Metro Vancouver, BC V5A 1S6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0313-3557","authenticated-orcid":false,"given":"Tyler J.","family":"Cuthbert","sequence":"additional","affiliation":[{"name":"Menrva Research Group, Schools of Mechatronic Systems &amp; Engineering Science, Simon Fraser University, Metro Vancouver, BC V5A 1S6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2309-9977","authenticated-orcid":false,"given":"Carlo","family":"Menon","sequence":"additional","affiliation":[{"name":"Menrva Research Group, Schools of Mechatronic Systems &amp; Engineering Science, Simon Fraser University, Metro Vancouver, BC V5A 1S6, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"898","DOI":"10.1136\/bjsports-2018-100493","article-title":"Is running associated with a lower risk of all-cause, cardiovascular and cancer mortality, and is the more the better? A systematic review and meta-analysis","volume":"54","author":"Pedisic","year":"2019","journal-title":"Br. J. Sports Med."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"434","DOI":"10.1136\/bjsports-2014-093885","article-title":"Health benefits of different sport disciplines for adults: Systematic review of observational and intervention studies with meta-analysis","volume":"49","author":"Oja","year":"2015","journal-title":"Br. J. Sports Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"469","DOI":"10.1136\/bjsm.2006.033548","article-title":"Incidence and determinants of lower extremity running injuries in long distance runners: A systematic review","volume":"41","author":"Siem","year":"2007","journal-title":"Br. J. Sports Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1113\/jphysiol.2007.139477","article-title":"Muscle fatigue: What, why and how it influences muscle function","volume":"586","author":"Enoka","year":"2007","journal-title":"J. Physiol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1249\/00005768-198205000-00012","article-title":"Psychophysical bases of perceived exertion","volume":"14","author":"Borg","year":"1982","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"92","DOI":"10.2340\/1650197719702239298","article-title":"Perceived exertion as an indicator of somatic stress","volume":"2","author":"Borg","year":"1970","journal-title":"Scand. J. Rehabil. Med."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"596","DOI":"10.1016\/j.gaitpost.2012.05.023","article-title":"The effect of pain on hip and knee kinematics during running in females with chronic patellofemoral pain","volume":"36","author":"Noehren","year":"2012","journal-title":"Gait Post."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1331","DOI":"10.1249\/MSS.0b013e3182880019","article-title":"Effect of Patellofemoral Pain on Strength and Mechanics after an Exhaustive Run","volume":"45","author":"Cobb","year":"2013","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"693","DOI":"10.1249\/MSS.0b013e3181f744f5","article-title":"Lower Extremity Kinematics in Runners with Patellofemoral Pain during a Prolonged Run","volume":"43","author":"Dierks","year":"2011","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1007\/s00421-012-2421-x","article-title":"Associations between Borg\u2019s rating of perceived exertion and physiological measures of exercise intensity","volume":"113","author":"Scherr","year":"2012","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"315","DOI":"10.1519\/JSC.0000000000000639","article-title":"Determination of Blood Lactate Training Zone Boundaries With Rating of Perceived Exertion in Runners","volume":"29","author":"Dantas","year":"2015","journal-title":"J. Strength Cond. Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"797","DOI":"10.1249\/00005768-199406000-00021","article-title":"Rating of perceived exertion and blood lactate concentration during submaximal running","volume":"26","author":"Steed","year":"1994","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1136\/bjsports-2015-094758","article-title":"Monitoring the athlete training response: Subjective self-reported measures trump commonly used objective measures: A systematic review","volume":"50","author":"Saw","year":"2015","journal-title":"Br. J. Sports Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"270","DOI":"10.1123\/ijspp.2018-0935","article-title":"Internal and External Training Load: 15 Years On","volume":"14","author":"Impellizzeri","year":"2019","journal-title":"Int. J. Sports Physiol. Perform."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Paquette, M.R., Napier, P.C., Willy, P.R.W., and Stellingwerff, T. (2020). Moving Beyond Weekly \u2018Distance\u2019: Optimizing Quantification of Training Load in Runners. J. Orthop. Sports Phys. Ther., 1\u201320.","DOI":"10.2519\/jospt.2020.9533"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Napier, C., Ryan, M., Menon, C., and Paquette, M.R. (2020). Session RPE in combination with training volume provides a better estimation of training responses in runners. J. Athl. Train., in press.","DOI":"10.4085\/1062-6050-573-19"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2507","DOI":"10.1249\/MSS.0000000000001707","article-title":"Positive Work Contribution Shifts from Distal to Proximal Joints during a Prolonged Run","volume":"50","author":"Sanno","year":"2018","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1007\/s004210000219","article-title":"Effects of marathon running on running economy and kinematics","volume":"82","author":"Pullinen","year":"2000","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"479","DOI":"10.1007\/s004210050363","article-title":"Energy cost and running mechanics during a treadmill run to voluntary exhaustion in humans","volume":"77","author":"Candau","year":"1998","journal-title":"Eur. J. Appl. Physiol. Occup. Physiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"998","DOI":"10.1097\/00005768-200206000-00015","article-title":"Impacts and kinematic adjustments during an exhaustive run","volume":"34","author":"Derrick","year":"2002","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1016\/S0167-9457(00)00013-0","article-title":"Effect of fatigue on leg kinematics and impact acceleration in long distance running","volume":"19","author":"Mizrahi","year":"2000","journal-title":"Hum. Mov. Sci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1917","DOI":"10.1249\/MSS.0b013e318259480d","article-title":"Effects of Fatigue on Running Mechanics Associated with Tibial Stress Fracture Risk","volume":"44","author":"Clansey","year":"2012","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"832","DOI":"10.1249\/01.MSS.0000126779.65353.CB","article-title":"The Effects of Knee Contact Angle on Impact Forces and Accelerations","volume":"36","author":"Derrick","year":"2004","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1090","DOI":"10.1016\/j.clinbiomech.2006.07.004","article-title":"The effect of lower extremity fatigue on shock attenuation during single-leg landing","volume":"21","author":"Coventry","year":"2006","journal-title":"Clin. Biomech."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"253","DOI":"10.1016\/0268-0033(95)00068-2","article-title":"Relationship between vertical ground reaction force and speed during walking, slow jogging, and running","volume":"11","author":"Keller","year":"1996","journal-title":"Clin. Biomech."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"831","DOI":"10.1162\/qjec.122.2.831","article-title":"Consumption Commitments and Risk Preferences","volume":"122","author":"Chetty","year":"2007","journal-title":"Q. J. Econ."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1016\/j.jsams.2013.05.013","article-title":"Kinematic changes during running-induced fatigue and relations with core endurance in novice runners","volume":"17","author":"Koblbauer","year":"2014","journal-title":"J. Sci. Med. Sport"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"832","DOI":"10.1055\/s-0032-1329958","article-title":"Changes in Running Mechanics and Spring-Mass Behaviour during a 5-km Time Trial","volume":"34","author":"Girard","year":"2013","journal-title":"Int. J. Sports Med."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"657","DOI":"10.1249\/01.MSS.0000158994.29358.71","article-title":"Kinetic Changes with Fatigue and Relationship to Injury in Female Runners","volume":"37","author":"Gerlach","year":"2005","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_30","first-page":"111","article-title":"The influence of fatigue on EMG and impact acceleration in running","volume":"7","author":"Mizrahi","year":"1997","journal-title":"Basic Appl. Myol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1062","DOI":"10.1080\/17461391.2019.1575912","article-title":"Altered multi-muscle coordination patterns in habitual forefoot runners during a prolonged, exhaustive run","volume":"19","author":"Jewell","year":"2019","journal-title":"Eur. J. Sport Sci."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"40","DOI":"10.1007\/s004210100508","article-title":"Surface EMG shows distinct populations of muscle activity when measured during sustained sub-maximal exercise","volume":"86","author":"Wakeling","year":"2001","journal-title":"Eur. J. Appl. Physiol."},{"key":"ref_33","first-page":"887","article-title":"Effects of fatigue on kinematics and kinetics during overground running: A systematic review","volume":"57","author":"Winter","year":"2016","journal-title":"J. Sports Med. Phys. Fit."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Strohrmann, C., Rossi, M., Arnrich, B., and Tr\u00f6ster, G. (2012, January 9\u201312). A Data-Driven Approach to Kinematic Analysis in Running Using Wearable Technology. Proceedings of the 2012 Ninth International Conference on Wearable and Implantable Body Sensor Networks, London, UK.","DOI":"10.1109\/BSN.2012.1"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Buckley, C., O\u2019Reilly, M., Whelan, D., Farrell, A.V., Clark, L., Longo, V., Gilchrist, M., Caulfield, B., and O\u2019Reilly, M.A. (2017, January 9\u201312). Binary classification of running fatigue using a single inertial measurement unit. Proceedings of the 2017 IEEE 14th International Conference on Wearable and Implantable Body Sensor Networks (BSN), Eindhoven, The Netherlands.","DOI":"10.1109\/BSN.2017.7936040"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1116","DOI":"10.1080\/00140139.2018.1442936","article-title":"A machine learning approach to detect changes in gait parameters following a fatiguing occupational task","volume":"61","author":"Baghdadi","year":"2018","journal-title":"Ergon"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"470","DOI":"10.1109\/TNSRE.2013.2291327","article-title":"Human Movement Analysis as a Measure for Fatigue: A Hidden Markov-Based Approach","volume":"22","author":"Karg","year":"2014","journal-title":"IEEE Trans. Neural Syst. Rehab. Eng."},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Gholami, M., Rezaei, A., Cuthbert, T.J., Napier, C., and Menon, C. (2019). Lower Body Kinematics Monitoring in Running Using Fabric-Based Wearable Sensors and Deep Convolutional Neural Networks. Sensors, 19.","DOI":"10.3390\/s19235325"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Gholami, M., Ejupi, A., Rezaei, A., Ferrone, A., and Menon, C. (2018, January 26\u201329). Estimation of Knee Joint Angle Using a Fabric-Based Strain Sensor and Machine Learning: A Preliminary Investigation. Proceedings of the 2018 7th IEEE International Conference on Biomedical Robotics and Biomechatronics (Biorob), Enschede, The Netherlands.","DOI":"10.1109\/BIOROB.2018.8487199"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Totaro, M., Poliero, T., Mondini, A., Lucarotti, C., Cairoli, G., Ortiz, J., and Beccai, L. (2017). Soft Smart Garments for Lower Limb Joint Position Analysis. Sensors, 17.","DOI":"10.20944\/preprints201709.0011.v1"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Rezaei, A., Cuthbert, T.J., Gholami, M., and Menon, C. (2019). Application-Based Production and Testing of a Core-Sheath Fiber Strain Sensor for Wearable Electronics: Feasibility Study of Using the Sensors in Measuring Tri-Axial Trunk Motion Angles. Sensors, 19.","DOI":"10.3390\/s19194288"},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Mattmann, C., Amft, O., Harms, H., Troster, G., and Clemens, F. (2007, January 11\u201313). Recognizing Upper Body Postures using Textile Strain Sensors. Proceedings of the 2007 11th IEEE International Symposium on Wearable Computers, Boston, MA, USA.","DOI":"10.1109\/ISWC.2007.4373773"},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Ferrone, A., Jiang, X., Maiolo, L., Pecora, A., Colace, L., and Menon, C. (2016, January 9\u201311). A fabric-based wearable band for hand gesture recognition based on filament strain sensors: A preliminary investigation. Proceedings of the 2016 IEEE Healthcare Innovation Point-Of-Care Technologies Conference (HI-POCT), Cancun, Mexico.","DOI":"10.1109\/HIC.2016.7797710"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"1678","DOI":"10.1002\/adfm.201504755","article-title":"Stretchable, Skin-Mountable, and Wearable Strain Sensors and Their Potential Applications: A Review","volume":"26","author":"Amjadi","year":"2016","journal-title":"Adv. Funct. Mater."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1080\/02640414.2016.1225972","article-title":"Sex differences in lower extremity kinematics and patellofemoral kinetics during running","volume":"35","author":"Almonroeder","year":"2016","journal-title":"J. Sports Sci."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1016\/j.ptsp.2018.05.019","article-title":"Kinematic predictors of loading during running differ by demographic group","volume":"32","author":"Harrison","year":"2018","journal-title":"Phys. Ther. Sport"},{"key":"ref_47","doi-asserted-by":"crossref","unstructured":"Rezaei, A., Ejupi, A., Gholami, M., Ferrone, A., and Menon, C. (2018, January 26\u201329). Preliminary Investigation of Textile-Based Strain Sensors for the Detection of Human Gait Phases Using Machine Learning. Proceedings of the 2018 7th IEEE International Conference on Biomedical Robotics and Biomechatronics (Biorob), Enschede, The Netherlands.","DOI":"10.1109\/BIOROB.2018.8487880"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1023\/A:1010933404324","article-title":"Random Forests","volume":"45","author":"Breiman","year":"2001","journal-title":"Mach. Learn."},{"key":"ref_49","first-page":"18","article-title":"Classification and regression by randomforest","volume":"2","author":"Liaw","year":"2002","journal-title":"R News"},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Khan, T., Lundgren, L., J\u00e4rpe, E., Olsson, C., and Viberg, P. (2019). A Novel Method for Classification of Running Fatigue Using Change-Point Segmentation. Sensors, 19.","DOI":"10.3390\/s19214729"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"1642","DOI":"10.1136\/bjsports-2017-098637","article-title":"Gait retraining: Out of the lab and onto the streets with the benefit of wearables","volume":"51","author":"Napier","year":"2017","journal-title":"Br. J. Sports Med."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"600","DOI":"10.1007\/s10439-013-0917-0","article-title":"Classifying lower extremity muscle fatigue during walking using machine learning and inertial sensors","volume":"42","author":"Zhang","year":"2013","journal-title":"Ann. Biomed. Eng."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1016\/bs.pbr.2018.09.012","article-title":"Chapter 11 The cardinal exercise stopper: Muscle fatigue, muscle pain or perception of effort?","volume":"Volume 240","author":"Marcora","year":"2018","journal-title":"Progress in Brain Research"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"3","DOI":"10.3389\/fphys.2012.00082","article-title":"Fatigue is a Brain-Derived Emotion that Regulates the Exercise Behavior to Ensure the Protection of Whole Body Homeostasis","volume":"3","author":"Noakes","year":"2012","journal-title":"Front. Physiol."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"679","DOI":"10.1007\/s40279-019-01229-z","article-title":"Rating of Perceived Effort: Methodological Concerns and Future Directions","volume":"50","author":"Halperin","year":"2019","journal-title":"Sports Med."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/19\/5573\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T10:14:41Z","timestamp":1760177681000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/19\/5573"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,9,29]]},"references-count":55,"journal-issue":{"issue":"19","published-online":{"date-parts":[[2020,10]]}},"alternative-id":["s20195573"],"URL":"https:\/\/doi.org\/10.3390\/s20195573","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,9,29]]}}}