{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T23:29:45Z","timestamp":1783034985325,"version":"3.54.6"},"reference-count":29,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2023,6,22]],"date-time":"2023-06-22T00:00:00Z","timestamp":1687392000000},"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>In recent years, there has been an exponential increase in the number of devices developed to measure or estimate physical exercise. However, before these devices can be used in a practical and research environment, it is necessary to determine their validity and reliability. The purpose of this study is to test the validity and reliability of a load cell sensor-based device (LC) for measuring the peak force (PFr) and the rate of force development (RFD) during the isometric mid-thigh pull (IMTP) test, using a force plate (FP) as the gold standard. Forty-two undergraduate sport science students (male and female) participated in this study. In a single session, they performed three repetitions of the IMTP test, being tested simultaneously with an LC device and a Kistler force platform (FP). The PFr and RFD data were obtained from the force-time curve of the FP and compared with the LC data, provided automatically by the software of the device (Smart Traction device\u00a9). The mean difference between the results obtained by the LC device and the gold-standard equipment (FP) was not significantly different (p &gt; 0.05), for both PFr and RFD, which suggests the validity of the ST results. Bland\u2013Altman analysis showed a small mean difference in PFr = 1.69 N, upper bound = 47.88 N, and lower bound = \u221251.27 N. RFD showed that the mean difference was \u22125.27 N\/s, upper limit = 44.36 N\/s, and lower limit = \u221254.91 N\/s. Our results suggest that the LC device can be used in the assessment of the isometric-mid-thigh-pull test as a valid and reliable tool. It is recommended that this device\u2019s users consider these research results before putting the ST into clinical practice.<\/jats:p>","DOI":"10.3390\/s23135832","type":"journal-article","created":{"date-parts":[[2023,6,23]],"date-time":"2023-06-23T02:34:07Z","timestamp":1687487647000},"page":"5832","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Validity and Reliability of a Load Cell Sensor-Based Device for Assessment of the Isometric Mid-Thigh Pull Test"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2642-945X","authenticated-orcid":false,"given":"Raynier","family":"Montoro-Bomb\u00fa","sequence":"first","affiliation":[{"name":"University of Coimbra, Research Unit for Sport and Physical Activity (CIDAF), Faculty of Sport Sciences and Physical Education, 3040-248 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2885-7666","authenticated-orcid":false,"given":"Beatriz Branquinho","family":"Gomes","sequence":"additional","affiliation":[{"name":"University of Coimbra, Research Unit for Sport and Physical Activity (CIDAF), Faculty of Sport Sciences and Physical Education, 3040-248 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1033-6985","authenticated-orcid":false,"given":"Am\u00e2ndio","family":"Santos","sequence":"additional","affiliation":[{"name":"University of Coimbra, Research Unit for Sport and Physical Activity (CIDAF), Faculty of Sport Sciences and Physical Education, 3040-248 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9619-8618","authenticated-orcid":false,"given":"Luis","family":"Rama","sequence":"additional","affiliation":[{"name":"University of Coimbra, Research Unit for Sport and Physical Activity (CIDAF), Faculty of Sport Sciences and Physical Education, 3040-248 Coimbra, Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"532","DOI":"10.1080\/14763141.2018.1498910","article-title":"Scaling isometric mid-thigh pull maximum strength in division I Athletes: Are we meeting the assumptions?","volume":"19","author":"Suchomel","year":"2020","journal-title":"Sports Biomech."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"478","DOI":"10.1123\/ijspp.2019-0217","article-title":"Normalization of Early Isometric Force Production as a Percentage of Peak Force During Multijoint Isometric Assessment","volume":"15","author":"Comfort","year":"2019","journal-title":"Int. J. Sports Physiol. Perform."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"279","DOI":"10.1136\/bmjmilitary-2021-001950","article-title":"Use of an isometric mid-thigh pull test during musculoskeletal rehabilitation: Can the criterion values from the updated British Army physical employment standards be used to inform UK Defence Rehabilitation practice?","volume":"168","author":"Walters","year":"2022","journal-title":"BMJ Mil. Health"},{"key":"ref_4","first-page":"878","article-title":"The importance of isometric maximum strength and peak rate-of-force development in sprint cycling","volume":"18","author":"Stone","year":"2004","journal-title":"J. Strength Cond. Res."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Dos\u2019Santos, T., Thomas, C., Comfort, P., McMahon, J.J., and Jones, P.A. (2017). Relationships between Isometric Force-Time Characteristics and Dynamic Performance. Sports, 5.","DOI":"10.3390\/sports5030068"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1378","DOI":"10.1519\/JSC.0000000000001201","article-title":"Validity and Reliability of a Portable Isometric Mid-Thigh Clean Pull","volume":"31","author":"James","year":"2017","journal-title":"J. Strength Cond. Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"407","DOI":"10.5114\/biolsport.2022.106149","article-title":"Test-retest reliability of isometric mid-thigh pull maximum strength assessment: A systematic review","volume":"39","author":"Grgic","year":"2022","journal-title":"Biol. Sport"},{"key":"ref_8","first-page":"573","article-title":"Relationships of isometric mid-thigh pull variables to weightlifting performance","volume":"53","author":"Beckham","year":"2013","journal-title":"J. Sport Med. Phys. Fit."},{"key":"ref_9","first-page":"53","article-title":"Normalizing expressions of strength in elite rugby league players","volume":"18","author":"Atkins","year":"2004","journal-title":"J. Strength Cond. Res."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Martin, E.A., and Beckham, G.K. (2020). Isometric Mid-Thigh Pull Performance in Rugby Players: A Systematic Literature Review. J. Funct. Morphol. Kinesiol., 5.","DOI":"10.3390\/jfmk5040091"},{"key":"ref_11","first-page":"741","article-title":"Force-time curve characteristics of dynamic and isometric muscle actions of elite women olympic weightlifters","volume":"19","author":"Haff","year":"2005","journal-title":"J. Strength Cond. Res."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Ruschel, C., Haupenthal, A., Jacomel, G.F., Fontana Hde, B., Santos, D.P., Scoz, R.D., and Roesler, H. (2015). Validity and reliability of an instrumented leg-extension machine for measuring isometric muscle strength of the knee extensors. J. Sport Rehabil., 24.","DOI":"10.1123\/jsr.2013-0122"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Macedo, M.C., Souza, M.A., Ferreira, K.R., Campos, L.O., Souza, I.S.O., Barbosa, M.A., Brito, C.J., Intelangelo, L., and Barbosa, A.C. (2022). Validity and Test-Retest Reliability of a Novel Push Low-Cost Hand-Held Dynamometer for Knee Strength Assessment during Different Force Ranges. Diagnostics, 12.","DOI":"10.3390\/diagnostics12010186"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1177\/1479972316687210","article-title":"Validity and reliability of strain gauge measurement of volitional quadriceps force in patients with COPD","volume":"14","author":"Demeyer","year":"2017","journal-title":"Chron. Respir. Dis."},{"key":"ref_15","first-page":"41","article-title":"The Helsinki Declaration","volume":"29","author":"Mondiale","year":"2010","journal-title":"Assist. Inferm. Ric."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Guppy, S.N., Brady, C.J., Kotani, Y., Stone, M.H., Medic, N., and Haff, G.G. (2018). The Effect of Altering Body Posture and Barbell Position on the Between-Session Reliability of Force-Time Curve Characteristics in the Isometric Mid-Thigh Pull. Sports, 6.","DOI":"10.3390\/sports6040162"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Bourgeois, F.A., Gamble, P., Gill, N.D., and McGuigan, M.R. (2017). Effects of a Six-Week Strength Training Programme on Change of Direction Performance in Youth Team Sport Athletes. Sports, 5.","DOI":"10.3390\/sports5040083"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1163","DOI":"10.1123\/ijspp.2016-0607","article-title":"Supercompensation Kinetics of Physical Qualities During a Taper in Team-Sport Athletes","volume":"12","author":"Marrier","year":"2017","journal-title":"Int. J. Sports Physiol. Perform."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2748","DOI":"10.1519\/JSC.0000000000002098","article-title":"The Effect of Hip Joint Angle on Isometric Midthigh Pull Kinetics","volume":"31","author":"Thomas","year":"2017","journal-title":"J. Strength Cond. Res."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1519\/JSC.0000000000000705","article-title":"A comparison of methods for determining the rate of force development during isometric midthigh clean pulls","volume":"29","author":"Haff","year":"2015","journal-title":"J. Strength Cond. Res."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Montoro-Bomb\u00fa, R., de la Paz Arencibia, L., Buzzichelli, C., Miranda-Oliveira, P., Fernandes, O., Santos, A., and Rama, L. (2022). The Validity of the Push Band 2.0 on the Reactive Strength Index Assessment in Drop Jump. Sensors, 22.","DOI":"10.3390\/s22134724"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1015526","DOI":"10.3389\/fbioe.2022.1015526","article-title":"Validity and reliability of the Output sport device for assessing drop jump performance","volume":"10","author":"Field","year":"2022","journal-title":"Front. Bioeng. Biotechnol."},{"key":"ref_23","unstructured":"Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences, L. Erlbaum Associates. [2nd ed.]."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1897","DOI":"10.1519\/JSC.0000000000001657","article-title":"Reliability and Validity of the Load-Velocity Relationship to Predict the 1RM Back Squat","volume":"31","author":"Banyard","year":"2017","journal-title":"J. Strength Cond. Res."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.jcm.2016.02.012","article-title":"A Guideline of Selecting and Reporting Intraclass Correlation Coefficients for Reliability Research","volume":"15","author":"Koo","year":"2016","journal-title":"J. Chiropr. Med."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"217","DOI":"10.2165\/00007256-199826040-00002","article-title":"Statistical methods for assessing measurement error (reliability) in variables relevant to sports medicine","volume":"26","author":"Atkinson","year":"1998","journal-title":"Sports Med."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Gaudet, J., and Handrigan, G. (2020). Assessing the Validity and Reliability of a Low-Cost Microcontroller-Based Load Cell Amplifier for Measuring Lower Limb and Upper Limb Muscular Force. Sensors, 20.","DOI":"10.3390\/s20174999"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Sung, K.-S., Yi, Y.G., and Shin, H.-I. (2019). Reliability and validity of knee extensor strength measurements using a portable dynamometer anchoring system in a supine position. BMC Musculoskelet. Disord., 20.","DOI":"10.1186\/s12891-019-2703-0"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1091","DOI":"10.1007\/s00421-016-3346-6","article-title":"Rate of force development: Physiological and methodological considerations","volume":"116","author":"Maffiuletti","year":"2016","journal-title":"Eur. J. Appl. Physiol."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/13\/5832\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T19:58:49Z","timestamp":1760126329000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/23\/13\/5832"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,6,22]]},"references-count":29,"journal-issue":{"issue":"13","published-online":{"date-parts":[[2023,7]]}},"alternative-id":["s23135832"],"URL":"https:\/\/doi.org\/10.3390\/s23135832","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,6,22]]}}}