{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T01:20:06Z","timestamp":1780536006702,"version":"3.54.1"},"reference-count":49,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,5,22]],"date-time":"2020-05-22T00:00:00Z","timestamp":1590105600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["Natural Sciences and Engineering Research Council"],"award-info":[{"award-number":["Natural Sciences and Engineering Research Council"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000024","name":"Canadian Institutes of Health Research","doi-asserted-by":"publisher","award":["Canadian Institutes of Health Research"],"award-info":[{"award-number":["Canadian Institutes of Health Research"]}],"id":[{"id":"10.13039\/501100000024","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001804","name":"Canada Research Chairs","doi-asserted-by":"publisher","award":["Canada Research Chairs Program"],"award-info":[{"award-number":["Canada Research Chairs Program"]}],"id":[{"id":"10.13039\/501100001804","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Abnormal running kinematics are associated with an increased incidence of lower extremity injuries among runners. Accurate and unobtrusive running kinematic measurement plays an important role in the detection of gait abnormalities and the prevention of injuries among runners. Inertial-based methods have been proposed to address this need. However, previous methods require cumbersome sensor setup or participant-specific calibration. This study aims to validate a shoe-mounted accelerometer for sagittal plane lower extremity angle measurement during running based on a deep learning approach. A convolutional neural network (CNN) architecture was selected as the regression model to generalize in inter-participant scenarios and to minimize poorly estimated joints. Motion and accelerometer data were recorded from ten participants while running on a treadmill at five different speeds. The reference joint angles were measured by an optical motion capture system. The CNN model predictions deviated from the reference angles with a root mean squared error (RMSE) of less than 3.5\u00b0 and 6.5\u00b0 in intra- and inter-participant scenarios, respectively. Moreover, we provide an estimation of six important gait events with a mean absolute error of less than 2.5\u00b0 and 6.5\u00b0 in intra- and inter-participants scenarios, respectively. This study highlights an appealing minimal sensor setup approach for gait analysis purposes.<\/jats:p>","DOI":"10.3390\/s20102939","type":"journal-article","created":{"date-parts":[[2020,5,22]],"date-time":"2020-05-22T10:18:18Z","timestamp":1590142698000},"page":"2939","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":77,"title":["Estimating Lower Extremity Running Gait Kinematics with a Single Accelerometer: A Deep Learning Approach"],"prefix":"10.3390","volume":"20","author":[{"given":"Mohsen","family":"Gholami","sequence":"first","affiliation":[{"name":"Menrva Research Group, Schools of Mechatronic Systems Engineering &amp; Engineering Science, Simon Fraser University, Metro Vancouver, BC V5A 1S6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"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 Engineering &amp; Engineering Science, Simon Fraser University, Metro Vancouver, BC V5A 1S6, Canada"},{"name":"Department of Physical Therapy, University of British Columbia, Vancouver, BC V6T 1Z4, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"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 Engineering &amp; Engineering Science, Simon Fraser University, Metro Vancouver, BC V5A 1S6, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1016\/j.jbiomech.2019.05.014","article-title":"Increased hip adduction during running is associated with patellofemoral pain and differs between males and females: A case-control study","volume":"91","author":"Neal","year":"2019","journal-title":"J. Biomech."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3023","DOI":"10.1177\/0363546518793657","article-title":"Is there a pathological gait associated with common soft tissue running injuries?","volume":"46","author":"Bramah","year":"2018","journal-title":"Am. J. Sports Med."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"3406","DOI":"10.1177\/0363546519879693","article-title":"A 10% increase in step rate improves running kinematics and clinical outcomes in runners with patellofemoral pain at 4 weeks and 3 months","volume":"47","author":"Bramah","year":"2019","journal-title":"Am. J. Sports Med."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"388","DOI":"10.1177\/0363546517736277","article-title":"Gait retraining for the reduction of injury occurrence in novice distance runners: 1-year follow-up of a randomized controlled trial","volume":"46","author":"Chan","year":"2018","journal-title":"Am. J. Sports Med."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"259","DOI":"10.1016\/j.gaitpost.2019.12.018","article-title":"Does fatigue alter step characteristics and stiffness during running?","volume":"76","year":"2020","journal-title":"Gait Posture"},{"key":"ref_6","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_7","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_8","first-page":"1","article-title":"Fatigue-related changes in running gait patterns persist in the days following a marathon race","volume":"1","author":"Clermont","year":"2019","journal-title":"J. Sport Rehabil."},{"key":"ref_9","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_10","doi-asserted-by":"crossref","first-page":"136","DOI":"10.2519\/jospt.2019.8587","article-title":"Real-time biofeedback of performance to reduce braking forces associated with running-related injury: An exploratory study","volume":"49","author":"Napier","year":"2018","journal-title":"J. Orthop. Sports Phys. Ther."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1111\/sms.12413","article-title":"In-field gait retraining and mobile monitoring to address running biomechanics associated with tibial stress fracture","volume":"26","author":"Willy","year":"2016","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1016\/j.ptsp.2020.03.001","article-title":"The effectiveness of real-time haptic feedback gait retraining for reducing resultant tibial acceleration with runners","volume":"43","author":"Sheerin","year":"2020","journal-title":"Phys. Ther. Sport"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"239","DOI":"10.1016\/j.gaitpost.2016.11.008","article-title":"25 years of lower limb joint kinematics by using inertial and magnetic sensors: A review of methodological approaches","volume":"51","author":"Picerno","year":"2017","journal-title":"Gait Posture"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Jiang, X., Gholami, M., Khoshnam, M., Eng, J.J., and Menon, C. (2019). Estimation of ankle joint power during walking using two inertial sensors. Sensors, 19.","DOI":"10.3390\/s19122796"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Weygers, I., Kok, M., Konings, M., Hallez, H., De Vroey, H., and Claeys, K. (2020). Inertial sensor-based lower limb joint kinematics: A methodological systematic review. Sensors, 20.","DOI":"10.3390\/s20030673"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"6891","DOI":"10.3390\/s140406891","article-title":"IMU-based joint angle measurement for gait analysis","volume":"14","author":"Seel","year":"2014","journal-title":"Sensors"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"79","DOI":"10.3182\/20140824-6-ZA-1003.02252","article-title":"An optimization-based approach to human body motion capture using inertial sensors","volume":"47","author":"Kok","year":"2014","journal-title":"IFAC Proc. Vol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1478","DOI":"10.1109\/TBME.2005.851475","article-title":"A new approach to accurate measurement of uniaxial joint angles based on a combination of accelerometers and gyroscopes","volume":"52","author":"Dejnabadi","year":"2005","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"9321","DOI":"10.3390\/s130709321","article-title":"Three dimensional gait analysis using wearable acceleration and gyro sensors based on quaternion calculations","volume":"13","author":"Tadano","year":"2013","journal-title":"Sensors"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2678","DOI":"10.1016\/j.jbiomech.2009.08.004","article-title":"Inertial sensor-based knee flexion\/extension angle estimation","volume":"42","author":"Cooper","year":"2009","journal-title":"J. Biomech."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"395","DOI":"10.1109\/TNSRE.2005.847353","article-title":"Compensation of magnetic disturbances improves inertial and magnetic sensing of human body segment orientation","volume":"13","author":"Roetenberg","year":"2005","journal-title":"IEEE Trans. Neural Syst. Rehabil. Eng."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1003","DOI":"10.1080\/10255842.2013.867481","article-title":"Driving a musculoskeletal model with inertial and magnetic measurement units","volume":"18","author":"Koning","year":"2015","journal-title":"Comput. Methods Biomech. Biomed. Engin."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"109278","DOI":"10.1016\/j.jbiomech.2019.07.022","article-title":"Estimation of gait kinematics and kinetics from inertial sensor data using optimal control of musculoskeletal models","volume":"95","author":"Dorschky","year":"2019","journal-title":"J. Biomech."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1016\/j.piutam.2011.04.027","article-title":"Implicit methods for efficient musculoskeletal simulation and optimal control","volume":"2","author":"Blana","year":"2011","journal-title":"Procedia IUTAM"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1574","DOI":"10.1109\/TNN.2008.2000808","article-title":"An instance-based algorithm with auxiliary similarity information for the estimation of gait kinematics from wearable sensors","volume":"19","author":"Goulermas","year":"2008","journal-title":"IEEE Trans. Neural Netw."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"120","DOI":"10.1016\/j.gaitpost.2007.11.001","article-title":"Predicting lower limb joint kinematics using wearable motion sensors","volume":"28","author":"Findlow","year":"2008","journal-title":"Gait Posture"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"218","DOI":"10.3389\/fphys.2018.00218","article-title":"Estimation of vertical ground reaction forces and sagittal knee kinematics during running using three inertial sensors","volume":"9","author":"Wouda","year":"2018","journal-title":"Front. Physiol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1029","DOI":"10.1016\/j.jbiomech.2007.12.003","article-title":"Ambulatory measurement of 3D knee joint angle","volume":"41","author":"Favre","year":"2008","journal-title":"J. Biomech."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1125","DOI":"10.1299\/jsmec.44.1125","article-title":"A method for gait analysis in a daily living environment by body-mounted instruments","volume":"44","author":"Ohtaki","year":"2001","journal-title":"JSME Int. J. C Mech. Syst."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"061006","DOI":"10.1115\/1.4006674","article-title":"Measurement of multi-segment foot joint angles during gait using a wearable system","volume":"134","author":"Rouhani","year":"2012","journal-title":"J. Biomech. Eng."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1557","DOI":"10.1109\/JSEN.2015.2503765","article-title":"Monitoring of hip and knee joint angles using a single inertial measurement unit during lower limb rehabilitation","volume":"16","author":"Bonnet","year":"2016","journal-title":"IEEE Sens. J."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Hu, X., Yao, C., and Soh, G.S. (2015, January 11\u201314). Performance evaluation of lower limb ambulatory measurement using reduced inertial measurement units and 3R gait model. Proceedings of the 2015 IEEE International Conference on Rehabilitation Robotics (ICORR), Singapore.","DOI":"10.1109\/ICORR.2015.7281257"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.gmod.2015.04.001","article-title":"Motion reconstruction using very few accelerometers and ground contacts","volume":"79","author":"Riaz","year":"2015","journal-title":"Graph. Models"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Mousas, C. (2017). Full-body locomotion reconstruction of virtual characters using a single inertial measurement unit. Sensors, 17.","DOI":"10.3390\/s17112589"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Lim, H., Kim, B., and Park, S. (2020). Prediction of lower limb kinetics and kinematics during walking by a single IMU on the lower back using machine learning. Sensors, 20.","DOI":"10.3390\/s20010130"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"2531","DOI":"10.1109\/TMC.2016.2623304","article-title":"Gazelle: Energy-efficient wearable analysis for running","volume":"16","author":"Liu","year":"2017","journal-title":"IEEE Trans. Mob. Comput."},{"key":"ref_37","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_38","doi-asserted-by":"crossref","first-page":"2164","DOI":"10.1111\/sms.13228","article-title":"Kinetic risk factors of running-related injuries in female recreational runners","volume":"28","author":"Napier","year":"2018","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1016\/0167-9457(89)90020-1","article-title":"Prediction of hip joint centre location from external landmarks","volume":"8","author":"Bell","year":"1989","journal-title":"Hum. Mov. Sci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"825","DOI":"10.2519\/jospt.2014.5367","article-title":"Ability of sagittal kinematic variables to estimate ground reaction forces and joint kinetics in running","volume":"44","author":"Wille","year":"2014","journal-title":"J. Orthop. Sports Phys. Ther."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1038\/s41592-019-0686-2","article-title":"SciPy 1.0\u2014Fundamental algorithms for scientific computing in python","volume":"17","author":"Virtanen","year":"2019","journal-title":"Nat. Methods"},{"key":"ref_42","first-page":"9","article-title":"Kinematic analysis of a six-degrees-of-freedom model based on ISB recommendation: A repeatability analysis and comparison with conventional gait model","volume":"2015","author":"Pezowicz","year":"2015","journal-title":"Appl. Bionics Biomech."},{"key":"ref_43","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_44","unstructured":"Chollet, F. (2019, August 10). Keras. Available online: https:\/\/keras.io\/."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"502","DOI":"10.1123\/jab.28.5.502","article-title":"Musculoskeletal attenuation of impact shock in response to knee angle manipulation","volume":"28","author":"Edwards","year":"2012","journal-title":"J. Appl. Biomech."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"115","DOI":"10.1007\/s12283-017-0255-9","article-title":"Estimating running spatial and temporal parameters using an inertial sensor","volume":"21","author":"Chew","year":"2018","journal-title":"Sports Eng."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"835","DOI":"10.1111\/sms.13396","article-title":"Shoe-mounted accelerometers should be used with caution in gait retraining","volume":"29","author":"Cheung","year":"2019","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"738","DOI":"10.2519\/jospt.2015.6019","article-title":"Biomechanical differences of foot-strike patterns during running: A systematic review with meta-analysis","volume":"45","author":"Almeida","year":"2015","journal-title":"J. Orthop. Sports Phys. Ther."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"024002","DOI":"10.1088\/1361-6579\/aafa87","article-title":"Measurement error of 3D kinematic and kinetic measures during overground endurance running in recreational runners between two test sessions separated by 48 h","volume":"40","author":"Stoneham","year":"2019","journal-title":"Physiol. Meas."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/10\/2939\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:31:27Z","timestamp":1760175087000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/10\/2939"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,5,22]]},"references-count":49,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2020,5]]}},"alternative-id":["s20102939"],"URL":"https:\/\/doi.org\/10.3390\/s20102939","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,5,22]]}}}