{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T05:21:21Z","timestamp":1779340881060,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,6,3]],"date-time":"2021-06-03T00:00:00Z","timestamp":1622678400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Background: This study presents an intelligent table tennis e-training system based on a neural network (NN) model that recognizes data from sensors built into an armband device, with the component values (performances scores) estimated through principal component analysis (PCA). Methods: Six expert male table tennis players on the National Youth Team (mean age 17.8 \u00b1 1.2 years) and seven novice male players (mean age 20.5 \u00b1 1.5 years) with less than 1 year of experience were recruited into the study. Three-axis peak forearm angular velocity, acceleration, and eight-channel integrated electromyographic data were used to classify both player level and stroke phase. Data were preprocessed through PCA extraction from forehand loop signals. The model was trained using 160 datasets from five experts and five novices and validated using 48 new datasets from one expert and two novices. Results: The overall model\u2019s recognition accuracy was 89.84%, and its prediction accuracies for testing and new data were 93.75% and 85.42%, respectively. Principal components corresponding to the skills \u201cexplosive force of the forearm\u201d and \u201cwrist muscle control\u201d were extracted, and their factor scores were standardized (0\u2013100) to score the skills of the players. Assessment results indicated that expert scores generally fell between 60 and 100, whereas novice scores were less than 70. Conclusion: The developed system can provide useful information to quantify expert-novice differences in fore-hand loop skills.<\/jats:p>","DOI":"10.3390\/s21113870","type":"journal-article","created":{"date-parts":[[2021,6,3]],"date-time":"2021-06-03T21:03:32Z","timestamp":1622754212000},"page":"3870","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Creating a Scoring System with an Armband Wearable Device for Table Tennis Forehand Loop Training: Combined Use of the Principal Component Analysis and Artificial Neural Network"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2199-4553","authenticated-orcid":false,"given":"Wen-Lan","family":"Wu","sequence":"first","affiliation":[{"name":"Department of Sports Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Department of Medical Research, Kaohsiung Medical University Hospital, Kaohsiung 80708, Taiwan"},{"name":"The Master Program of Long-Term Care in Aging, College of Nursing, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Ph.D. Program in Biomedical Engineering, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jing-Min","family":"Liang","sequence":"additional","affiliation":[{"name":"Department of Sports Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chien-Fei","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Sports Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kuei-Lan","family":"Tsai","sequence":"additional","affiliation":[{"name":"Physical Education Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7768-0997","authenticated-orcid":false,"given":"Nian-Shing","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Applied Foreign Languages, National Yunlin University of Science & Technology, Yunlin 64002, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6309-9859","authenticated-orcid":false,"given":"Kuo-Chin","family":"Lin","sequence":"additional","affiliation":[{"name":"Center for Physical and Health Education, Si Wan College, National Sun Yat-sen University, Kaohsiung 80424, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0206-1010","authenticated-orcid":false,"given":"Ing-Jer","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Computer Science and Engineering, National Sun Yat-sen University, Kaohsiung 80424, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2985","DOI":"10.1016\/j.proeng.2010.04.099","article-title":"Can interactive textiles influence a novice\u2019s throwing technique?","volume":"2","author":"Helmer","year":"2010","journal-title":"Procedia Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1080\/10691898.2014.11889702","article-title":"Analyzing Exercise Training Effect and Its Impact on Cardiorespiratory and Cardiovascular Fitness","volume":"22","author":"Laumakis","year":"2014","journal-title":"J. Stat. Educ."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Raina, A., Lakshmi, T.G., and Murthy, S. (2017, January 3\u20137). CoMBaT: Wearable Technology Based Training System for Novice Badminton Players. Proceedings of the 2017 IEEE 17th International Conference on Advanced Learning Technologies, Timisoara, Romania.","DOI":"10.1109\/ICALT.2017.96"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Abreu, J.G., Teixeira, J.M., Figueiredo, L.S., and Teichrieb, V. (2016, January 21\u201324). Evaluating Sign Language Recognition Using the Myo Armband. Proceedings of the 2016 XVIII Symposium on Virtual and Augmented Reality (SVR), Engramado, Brazil.","DOI":"10.1109\/SVR.2016.21"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Boyali, A., Hashimoto, N., and Matsumoto, O. (2015, January 27\u201330). Hand posture and gesture recognition using myo armband and spectral collaborative representation based classification. Proceedings of the 2015 IEEE 4th Global Conference on Consumer Electronics (GCCE), Osaka, Japan.","DOI":"10.1109\/GCCE.2015.7398619"},{"key":"ref_6","unstructured":"Masson, S., Fortuna, F., Moura, F., and Soriano, D. (2016, January 16\u201320). Integrating myo armband for the control of myoelectric upper limb prosthesis. Proceedings of the XXV Congresso Brasileiro de Engenharia Biom\u00e9dica, Paran\u00e1, Brazil."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Kr\u00e4uter, N., L\u00f6sing, S., Bauer, G., Schwering, L., and Seuter, M. (2016, January 12\u201316). Supporting safety in cycling groups using led\u2013augmented gestures. Proceedings of the 2016 ACM International Joint Conference on Pervasive and Ubiquitous Computing Adjunct, Heidelberg, Germany.","DOI":"10.1145\/2968219.2968573"},{"key":"ref_8","first-page":"1","article-title":"Controlling a robot using a wearable device (MYO)","volume":"3","author":"Sathiyanarayanan","year":"2015","journal-title":"Int. J. Eng. Dev. Res."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"701","DOI":"10.1007\/s13246-019-00770-5","article-title":"Applying EMG technology in medial and lateral elbow enthesopathy treatment using Myo motion controller","volume":"42","author":"Szklanny","year":"2019","journal-title":"Australas. Phys. Eng. Sci. Med."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Sathiyanarayanan, M., and Rajan, S. (2016, January 5\u20139). Myo armband for physiotherapy healthcare: A case study using gesture recognition application. Proceedings of the 2016 8th International Conference on Communication Systems and Networks, Bangalore, India.","DOI":"10.1109\/COMSNETS.2016.7439933"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"228","DOI":"10.9734\/BJMCS\/2011\/623","article-title":"Tracking table tennis balls in real match scenes for umpiring applications","volume":"1","author":"Wong","year":"2011","journal-title":"Br. J. Math. Comput. Sci."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"297","DOI":"10.1016\/j.proeng.2011.05.088","article-title":"Design, development and construction of a monitoring table tennis net","volume":"13","author":"Gastinger","year":"2011","journal-title":"Procedia Eng."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Blank, P., Kautz, T., and Eskofier, B.M. (2016). Ball impact localization on table tennis rackets using piezo\u2013electric sensors. Proceedings of the 2016 ACM International Symposium on New Ideas, New Paradigms and Reflections on Programming and Software, Association for Computing Machinery.","DOI":"10.1145\/2971763.2971778"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Blank, P., Groh, B.H., and Eskofier, B.M. (2017, January 11\u201315). Ball speed and spin estimation in table tennis using a racket\u2013mounted inertial sensor. Proceedings of the 2017 ACM International Symposium on Wearable Computers, Maui, HI, USA.","DOI":"10.1145\/3123021.3123040"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"B-2","DOI":"10.1299\/jsmeshd.2018.B-2","article-title":"Application of IMU\u2013based Motion Measurement Methods to Table Tennis Coaching","volume":"Volume 2018","author":"Nonaka","year":"2018","journal-title":"Proceedings of the Symposium on Sports and Human Dynamics"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Blank, P., Ho\u00dfbach, J., Schuldhaus, D., and Eskofier, B.M. (2015, January 9\u201311). Sensor\u2013based stroke detection and stroke type classification in table tennis. Proceedings of the 2015 ACM International Symposium on Wearable Computers, Osaka, Japan.","DOI":"10.1145\/2802083.2802087"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"106504","DOI":"10.1016\/j.dib.2020.106504","article-title":"Data acquired by a single object sensor for the detection and quality evaluation of table tennis forehand strokes","volume":"33","author":"Tabrizi","year":"2020","journal-title":"Data Brief"},{"key":"ref_18","unstructured":"Sharma, M., Anand, A., Srivastava, R., and Kaligounder, L. (2018). Wearable audio and IMU based shot detection in racquet sports. arXiv."},{"key":"ref_19","first-page":"1","article-title":"Using Wearable Inertial Sensors to Estimate Kinematic Parameters and Variability in the Table Tennis Topspin Forehand Stroke","volume":"2020","author":"Winiarski","year":"2020","journal-title":"Appl. Bionics Biomech."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Wang, H., Li, L., Chen, H., Li, Y., Qiu, S., and Gravina, R. (2019, January 2\u20133). Motion Recognition for Smart Sports Based on Wearable Inertial Sensors. Proceedings of the Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, Florence, Italy.","DOI":"10.1007\/978-3-030-34833-5_10"},{"key":"ref_21","unstructured":"Yin, C. (2018, January 29\u201330). Application of accelerometer in table tennis action recognition. Proceedings of the 5th International Conference on Electrical and Electronics Engineering and Computer Science, Beijing, China."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Dokic, K., Mesic, T., and Martinovic, M. (2020, January 24\u201325). Table Tennis Forehand and Backhand Stroke Recognition Based on Neural Network. Proceedings of the Communicational Conference on Advances in Computinger and Informataion Science, Valletta, Malta.","DOI":"10.1007\/978-981-15-6634-9_3"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Fu, Z., Shu, K.-I., and Zhang, H. (2019, January 29\u201330). Ping Pong Motion Recognition based on Smart Watch. Proceedings of the 3rd International Conference on Mechatronics Engineering and Information Technology, Dalian, China.","DOI":"10.2991\/icmeit-19.2019.99"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Liu, R., Wang, Z., Shi, X., Zhao, H., Qiu, S., Li, J., and Yang, N. (2019, January 10\u201312). Table Tennis Stroke Recognition Based on Body Sensor Network. Proceedings of the International Conference on Internet and Distributed Computing Systems, Naples, Italy.","DOI":"10.1007\/978-3-030-34914-1_1"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"167055","DOI":"10.1109\/ACCESS.2019.2953772","article-title":"Recognizing ping\u2013pong motions using inertial data based on machine learning classification algorithms","volume":"7","author":"Zhang","year":"2019","journal-title":"IEEE Access"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Lim, S.-M., Oh, H.-C., Kim, J., Lee, J., and Park, J. (2018). LSTM-Guided Coaching Assistant for Table Tennis Practice. Sensors, 18.","DOI":"10.3390\/s18124112"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1350010","DOI":"10.1142\/S0219519413500103","article-title":"The analysis of upper limb movement and emg activation during the snatch under various loading conditions","volume":"13","author":"Chen","year":"2013","journal-title":"J. Mech. Med. Biol."},{"key":"ref_28","first-page":"25","article-title":"Myoelectric comparison of table tennis forehand stroke using different ball sizes","volume":"36","author":"Medved","year":"2006","journal-title":"Acta. Univ. Palacki. Olomuc. Gymn."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1537","DOI":"10.1016\/j.jse.2019.01.021","article-title":"Electromyographic analysis of shoulder girdle muscle activation while performing a forehand topspin in elite table tennis athletes with and without shoulder impingement syndrome","volume":"28","author":"Meghdadi","year":"2019","journal-title":"J. Shoulder Elb. Surg."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1033","DOI":"10.1016\/j.jbmt.2017.02.002","article-title":"The effects of strengthening exercises for wrist flexors and extensors on muscle strength and counter\u2013stroke performance in amateur table tennis players","volume":"21","author":"Chanavirut","year":"2017","journal-title":"J. Bodyw. Mov. Ther."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1016\/j.bspc.2015.09.001","article-title":"Spectral collaborative representation based classification for hand gestures recognition on electro\u2013myography signals","volume":"24","author":"Boyali","year":"2016","journal-title":"Biomed. Signal Process Control"},{"key":"ref_32","unstructured":"The Myo Team (2018, July 02). Myo Support. Available online: https:\/\/support.getmyo.com\/hc\/en-us\/."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Bangaru, S.S., Wang, C., and Aghazadeh, F. (2020). Data Quality and Reliability Assessment of Wearable EMG and IMU Sensor for Construction Activity Recognition. Sensors, 20.","DOI":"10.3390\/s20185264"},{"key":"ref_34","unstructured":"Montoya-Leal, V., Orozco-Duque, A., Ugarte, J.P., Portela, M.A., Franco, J.C., and Perez, V.Z. (2014, January 29\u201331). Assessment protocol of wrist flexion and extension to support processes in occupational health using Myo Armband. Proceedings of the VII Latin American Congress on Biomedical Engineering, Paran\u00e1, Argentina."},{"key":"ref_35","first-page":"1","article-title":"Lower limb muscle activity during table tennis strokes","volume":"17","author":"Dorel","year":"2017","journal-title":"Sports Biomech."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1515\/hukin-2017-0182","article-title":"Comparative Study of Kinematics and Muscle Activity Between Elite and Amateur Table Tennis Players During Topspin Loop Against Backspin Movements","volume":"64","author":"Wang","year":"2018","journal-title":"J. Hum. Kinet."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Yu, C., Shao, S., Awrejcewicz, J., Baker, J.S., and Gu, Y. (2019). Lower Limb Maneuver Investigation of Chasse Steps Among Male Elite Table Tennis Players. Medicina, 55.","DOI":"10.3390\/medicina55040097"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"555","DOI":"10.1016\/j.procs.2020.03.125","article-title":"Online detection and classification of in\u2013corrected played strokes in table tennis using ir depth camera","volume":"170","author":"Hegazy","year":"2020","journal-title":"Procedia Comput. Sci."},{"key":"ref_39","unstructured":"Tsai, C., Pan, K., Huang, K., Chang, T., Hsueh, Y., Wang, L., and Chang, S. (2010, January 19\u201323). The surface emg activity of the upper limb muscles in table tennis forehand drives. Proceedings of the 28 International Conference on Biomechanics in Sports, Marquette, MI, USA."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/11\/3870\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:10:41Z","timestamp":1760163041000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/11\/3870"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,3]]},"references-count":39,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2021,6]]}},"alternative-id":["s21113870"],"URL":"https:\/\/doi.org\/10.3390\/s21113870","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,3]]}}}