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We evaluated a quasi-direct-drive (QDD) active upper-limb exoskeleton during simulated overhead work, providing simultaneous metabolic, electromyographic, and kinematic assessment of QDD actuation under static and dynamic conditions. Seven healthy males completed within-subject comparisons of without-exoskeleton (WO) and with-exoskeleton (WE) conditions during dynamic screwing (5 min) and static holding (2.5 min, 3 kg). During static holding, the exoskeleton achieved substantial shoulder offloading (Upper Trapezius: \u221268.2%, 6\/6 participants, p = 0.031, d = 3.61; Anterior Deltoid: \u221243.6%) and improved postural stability (32\u201341% variability reduction). However, metabolic cost increased during both static (+57.2%) and dynamic (+30.6%) tasks, while movement smoothness degraded. These findings extend prior task-dependent exoskeleton observations to QDD actuation, revealing that intrinsic backdrivability does not eliminate whole-body energy penalties from device mass. The exoskeleton exhibits task-dependent effectiveness: potentially suitable for prolonged static overhead holding but not currently recommended for dynamic assembly without mass reduction and control refinement.<\/jats:p>","DOI":"10.3390\/bioengineering13040423","type":"journal-article","created":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T03:11:28Z","timestamp":1775445088000},"page":"423","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Task-Dependent Effectiveness of a Quasi-Direct-Drive Upper-Limb Exoskeleton: Shoulder Muscle Offloading Versus Metabolic Cost in Overhead Work"],"prefix":"10.3390","volume":"13","author":[{"given":"Yongxuan","family":"Hong","sequence":"first","affiliation":[{"name":"College of Engineering, Southern University of Science and Technology, Shenzhen 518055, China"},{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiying","family":"Du","sequence":"additional","affiliation":[{"name":"China Southern Airlines Co., Ltd., Guangzhou 510470, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-4336-3898","authenticated-orcid":false,"given":"Sida","family":"Du","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yue","family":"Ma","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3907-0618","authenticated-orcid":false,"given":"Xiangyang","family":"Wang","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4855-9914","authenticated-orcid":false,"given":"Chunjie","family":"Chen","sequence":"additional","affiliation":[{"name":"Guangdong Provincial Key Lab of Robotics and Intelligent System, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/j.jelekin.2003.09.015","article-title":"Work-related musculoskeletal disorders: The epidemiologic evidence and the debate","volume":"14","author":"Punnett","year":"2004","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Hosseini, Z.S., Mokhtarinia, H.R., Vahedi, M., and Melloh, M. (2025). Prevalence and multivariate analysis of risk factors associated with musculoskeletal disorders among automotive assembly workers: A cross-sectional study. BMC Public Health, 25.","DOI":"10.1186\/s12889-025-23987-4"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"He, X., Xiao, B., Wu, J., Li, Y., Zhang, Y., Wang, Q., and Liu, H. (2023). Prevalence of work-related musculoskeletal disorders among workers in the automobile manufacturing industry in China: A systematic review and meta-analysis. BMC Public Health, 23.","DOI":"10.1186\/s12889-023-16896-x"},{"key":"ref_4","first-page":"755","article-title":"Work-related upper limb disorders and risk assessment among automobile manufacturing workers: A retrospective cohort analysis","volume":"64","author":"Monaco","year":"2019","journal-title":"Work"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"446","DOI":"10.1202\/0002-8894(2001)062<0446:FAELDI>2.0.CO;2","article-title":"Fatigue and endurance limits during intermittent overhead work","volume":"62","author":"Nussbaum","year":"2001","journal-title":"Am. Ind. Hyg. Assoc. J."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"53","DOI":"10.3233\/OER-2008-8105","article-title":"Overhead work: Identification of evidence-based exposure guideline","volume":"8","author":"Grieve","year":"2008","journal-title":"Occup. Ergon."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Macdonald, W., and Oakman, J. (2015). Requirements for more effective prevention of work-related musculoskeletal disorders. BMC Musculoskelet. Disord., 16.","DOI":"10.1186\/s12891-015-0750-8"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"671","DOI":"10.1080\/00140139.2015.1081988","article-title":"Exoskeletons for industrial application and their potential effects on physical work load","volume":"59","author":"Bosch","year":"2016","journal-title":"Ergonomics"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1016\/j.apergo.2017.11.004","article-title":"Assessment of an active industrial exoskeleton to aid dynamic lifting and lowering manual handling tasks","volume":"68","author":"Huysamen","year":"2018","journal-title":"Appl. Ergon."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1002\/ajim.23080","article-title":"Industrial exoskeletons: Need for intervention effectiveness research","volume":"63","author":"Howard","year":"2020","journal-title":"Am. J. Ind. Med."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Xu, J., Chen, S., Li, S., Liu, Y., Wan, H., Xu, Z., and Zhang, C. (2025). A survey on design and control methodologies of high-torque-density joints for compliant lower-limb exoskeleton. Sensors, 25.","DOI":"10.3390\/s25134016"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"509","DOI":"10.1109\/TRO.2016.2640183","article-title":"Proprioceptive actuator design in the MIT Cheetah: Impact mitigation and high-bandwidth physical interaction for dynamic legged robots","volume":"33","author":"Wensing","year":"2017","journal-title":"IEEE Trans. Robot."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Liu, L.-K., Chien, T.-C., Chen, Y.-L., Fu, L.-C., and Lai, J.-S. (2019, January 6\u20138). Sensorless Control with Friction and Human Intention Estimation of Exoskeleton Robot for Upper-Limb Rehabilitation. Proceedings of the 2019 IEEE International Conference on Robotics and Biomimetics (ROBIO), Dali, China.","DOI":"10.1109\/ROBIO49542.2019.8961760"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1794","DOI":"10.1109\/TMECH.2020.2995134","article-title":"Quasi-direct drive actuation for a lightweight hip exoskeleton with high backdrivability and high bandwidth","volume":"25","author":"Yu","year":"2020","journal-title":"IEEE ASME Trans. Mechatron."},{"key":"ref_15","first-page":"339","article-title":"Design of a parallel hip exoskeleton and its system implementation based on human-machine integrated dynamics","volume":"46","author":"Wang","year":"2024","journal-title":"Robot"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1186\/s10033-023-00883-9","article-title":"Design and analysis of a novel shoulder exoskeleton based on a parallel mechanism","volume":"36","author":"Niu","year":"2023","journal-title":"Chin. J. Mech. Eng."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"87","DOI":"10.5312\/wjo.v3.i6.87","article-title":"Assessment of scapulohumeral rhythm for scapular plane shoulder elevation using a modified digital inclinometer","volume":"3","author":"Scibek","year":"2012","journal-title":"World J. Orthop."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Andrade, R.L., Figueiredo, J., Fonseca, P., Vilas-Boas, J.P., Silva, M.T., and Santos, C.P. (2024). Human-robot joint misalignment, physical interaction, and gait kinematic assessment in ankle-foot orthoses. Sensors, 24.","DOI":"10.3390\/s24010246"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Pascoletti, G., Di Natali, C., Caldwell, D.G., Sposito, M., Bianconi, F., and Zanetti, E.M. (2025). The exoskeleton-human body system: A multibody model for fitting design analyses. Int. J. Interact. Des. Manuf. (IJIDeM), 1\u201315.","DOI":"10.1007\/s12008-025-02376-6"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"315","DOI":"10.1016\/j.apergo.2018.02.025","article-title":"Assessing the influence of a passive, upper extremity exoskeletal vest for overhead work","volume":"70","author":"Kim","year":"2018","journal-title":"Appl. Ergon."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Song, G., Moon, J., Kim, J., and Lee, G. (2024). Development of quasi-passive back-support exoskeleton with compact variable gravity compensation module and bio-inspired hip joint mechanism. Biomimetics, 9.","DOI":"10.3390\/biomimetics9030173"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Kuli\u015b, S., Pietraszewski, P., and Callegari, B. (2025). Characteristics of post-exercise lower limb muscle tremor among speed skaters. Sensors, 25.","DOI":"10.3390\/s25144301"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Hennah, C., Ellis, G., and Doumas, M. (2021). Dual task walking in healthy aging: Effects of narrow and wide walking paths. PLoS ONE, 16.","DOI":"10.1371\/journal.pone.0261647"},{"key":"ref_24","first-page":"1285","article-title":"Designing for dynamics: Underactuation and inertia as first principles in bipedal robots","volume":"14","author":"Bhatt","year":"2025","journal-title":"Int. J. Sci. Res."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1186\/s12984-021-00906-3","article-title":"Review of control strategies for lower-limb exoskeletons to assist gait","volume":"18","author":"Baud","year":"2021","journal-title":"J. Neuroeng. Rehabil."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"117","DOI":"10.3390\/hearts3040014","article-title":"Influence of exoskeleton use on cardiac index","volume":"3","author":"Schalk","year":"2022","journal-title":"Hearts"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"646","DOI":"10.1249\/MSS.0000000000002833","article-title":"Modeling the metabolic costs of heavy military backpacking","volume":"54","author":"Looney","year":"2022","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1944","DOI":"10.1109\/LRA.2025.3528229","article-title":"Funabot-sleeve: A wearable device employing McKibben artificial muscles for haptic sensation in the forearm","volume":"10","author":"Peng","year":"2025","journal-title":"IEEE Robot. Autom. Lett."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1427","DOI":"10.1007\/s11517-024-03280-z","article-title":"Impact of backpack load during walking: An sEMG and biomechanical analysis","volume":"63","author":"Matur","year":"2025","journal-title":"Med. Biol. Eng. Comput."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"541","DOI":"10.1038\/s41598-022-26934-0","article-title":"Lifespan changes in postural control","volume":"13","author":"Kliegl","year":"2023","journal-title":"Sci. Rep."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"933","DOI":"10.1002\/j.2040-4603.2012.tb00419.x","article-title":"Oxygen uptake kinetics","volume":"2","author":"Poole","year":"2012","journal-title":"Compr. Physiol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1367","DOI":"10.1038\/s42003-021-02879-4","article-title":"Back to feedback: Aberrant sensorimotor control in music performance under pressure","volume":"4","author":"Furuya","year":"2021","journal-title":"Commun. Biol."},{"key":"ref_33","first-page":"e433","article-title":"Brief history of the uncontrolled manifold hypothesis and its role in motor control","volume":"18","author":"Latash","year":"2024","journal-title":"Braz. J. Mot. Behav."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1080\/00140139.2011.586061","article-title":"A critical review on physical factors and functional characteristics that may explain a sex\/gender difference in work-related neck\/shoulder disorders","volume":"55","year":"2012","journal-title":"Ergonomics"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Zhang, X., Qu, Y., Zhang, G., Wang, Z., Chen, C., and Xu, X. (2025). Review of sEMG for exoskeleton robots: Motion intention recognition techniques and applications. Sensors, 25.","DOI":"10.3390\/s25082448"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Bezzini, R., Gualtieri, L., Zucchelli, A., Zanotti, A., Faglia, R., and Magnani, S. (2024). Design and experimental evaluation of multiple 3D-printed reduction gearboxes for wearable exoskeletons. Robotics, 13.","DOI":"10.20944\/preprints202410.2002.v1"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1080\/24725838.2022.2124325","article-title":"Exploring the change in metabolic cost of walking before and after familiarization with a passive load-bearing exoskeleton: A caseseries","volume":"10","author":"Telonio","year":"2022","journal-title":"IISE Trans. Occup. Ergon. Hum. Factors"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1080\/00140139.2014.961566","article-title":"Effects of job rotation on musculoskeletal complaints and related work exposures: A systematic literature review","volume":"58","author":"Leider","year":"2015","journal-title":"Ergonomics"}],"container-title":["Bioengineering"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2306-5354\/13\/4\/423\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T04:25:45Z","timestamp":1775449545000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2306-5354\/13\/4\/423"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,3]]},"references-count":38,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2026,4]]}},"alternative-id":["bioengineering13040423"],"URL":"https:\/\/doi.org\/10.3390\/bioengineering13040423","relation":{},"ISSN":["2306-5354"],"issn-type":[{"value":"2306-5354","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,3]]}}}