{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T05:14:36Z","timestamp":1775625276010,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T00:00:00Z","timestamp":1775174400000},"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>This two-step design used the unilateral bench press to examine the effect of breast cancer surgery on upper-limb muscle activation under low and moderate fatigue conditions. First, we studied the proper method to normalize the activation values obtained during dynamic contractions. For that, the muscle activation was relativized to the maximal value obtained during (i) an isometric contraction (ISONorm), and the concentric phase of the (ii) repetition maximum load (1RMNorm), and (iii) the first three repetitions of an 80% 1RM set (Max80%Norm). The normalization method with the lowest inter-subject variability was further used to compare the muscle activation of the affected and non-affected sides of twelve women who underwent unilateral breast surgery (eight mastectomies and four lumpectomies). Both sides were tested using dynamic sets at 60 and 80% of their 1RM until reaching 40% velocity loss (VL). Repetitions completed at each %1RM were then divided into two groups: low fatigue (first half of repetitions) and moderate fatigue (second half of repetitions). On results, the ISONorm and the Max80%Norm showed the highest (mean CV = 32.9%) and lowest (mean CV = 12.9%) inter-subject variability, respectively. The affected side showed higher activation for the deltoid and triceps (\u0394 = 6.9 to 15.9%) but lower for the pectoralis (\u0394 = \u22125.7 to \u221213.2%) against 60% 1RM. These differences were lower and without a consistent trend against 80% 1RM. Between-side comparisons were not significant for either 60% 1RM (p &gt; 0.270) or 80% 1RM (p &gt; 0.500). Although these results should be interpreted with caution due to the small and heterogeneous sample, our analyses did not reveal meaningful differences in upper-limb muscle activation following breast cancer surgery.<\/jats:p>","DOI":"10.3390\/s26072228","type":"journal-article","created":{"date-parts":[[2026,4,6]],"date-time":"2026-04-06T01:12:33Z","timestamp":1775437953000},"page":"2228","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Effect of Breast Cancer Surgery on Upper-Limb Muscle Activation"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2360-8847","authenticated-orcid":false,"given":"Francisco","family":"Franco-L\u00f3pez","sequence":"first","affiliation":[{"name":"Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, 30720 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0638-5859","authenticated-orcid":false,"given":"Alejandro","family":"Hern\u00e1ndez-Belmonte","sequence":"additional","affiliation":[{"name":"Department of Sports Sciences, Faculty of Medicine, Health and Sports, Universidad Europea de Madrid, 28670 Madrid, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ana Mar\u00eda","family":"Garc\u00eda-Segura","sequence":"additional","affiliation":[{"name":"Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, 30720 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-8737-5664","authenticated-orcid":false,"given":"Jaime","family":"L\u00f3pez-Bueno","sequence":"additional","affiliation":[{"name":"Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, 30720 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9435-8163","authenticated-orcid":false,"given":"Alejandro","family":"Mart\u00ednez-Cava","sequence":"additional","affiliation":[{"name":"Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, 30720 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2446-1875","authenticated-orcid":false,"given":"Javier","family":"Courel-Ib\u00e1\u00f1ez","sequence":"additional","affiliation":[{"name":"Department of Physical Education and Sports, Faculty of Education and Sport Sciences, University of Granada, 52005 Melilla, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6087-1583","authenticated-orcid":false,"given":"Jes\u00fas G.","family":"Pallar\u00e9s","sequence":"additional","affiliation":[{"name":"Human Performance and Sports Science Laboratory, Faculty of Sport Sciences, University of Murcia, 30720 Murcia, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,3]]},"reference":[{"key":"ref_1","first-page":"229","article-title":"Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries","volume":"74","author":"Bray","year":"2024","journal-title":"CA Cancer J. Clin."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1016\/j.clbc.2019.01.006","article-title":"The Global and Regional Survival Rate of Women with Breast Cancer: A Systematic Review and Meta-analysis","volume":"19","author":"Maajani","year":"2019","journal-title":"Clin. Breast Cancer"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"102375","DOI":"10.1016\/j.ctrv.2022.102375","article-title":"Adjuvant and neoadjuvant breast cancer treatments: A systematic review of their effects on mortality","volume":"105","author":"Kerr","year":"2022","journal-title":"Cancer Treat. Rev."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"103759","DOI":"10.1016\/j.critrevonc.2022.103759","article-title":"The impact of local therapies for breast cancer on shoulder muscle health and function","volume":"177","author":"Leonardis","year":"2022","journal-title":"Crit. Rev. Oncol. Hematol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"103071","DOI":"10.1016\/j.jelekin.2025.103071","article-title":"Quantifying the influence of radiation therapy on functional shoulder health indicators in breast cancer patients: An exploratory study","volume":"85","author":"Valerio","year":"2025","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1016\/S0936-6555(98)80063-0","article-title":"Shoulder movement after the treatment of early stage breast cancer","volume":"10","author":"Sugden","year":"1998","journal-title":"Clin. Oncol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"835","DOI":"10.1080\/02841860801961257","article-title":"Arm and shoulder morbidity in breast cancer patients after breast-conserving therapy versus mastectomy","volume":"47","author":"Nesvold","year":"2008","journal-title":"Acta Oncol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1054\/brst.1999.0087","article-title":"Physiotherapy treatment of late symptoms following surgical treatment of breast cancer","volume":"9","author":"Lauridsen","year":"2000","journal-title":"Breast"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"105666","DOI":"10.1016\/j.clinbiomech.2022.105666","article-title":"An evaluation of upper limb strength and range of motion of breast cancer survivors immediately following treatment","volume":"96","author":"Maciukiewicz","year":"2022","journal-title":"Clin. Biomech."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1409","DOI":"10.1249\/MSS.0b013e3181e0c112","article-title":"American college of sports medicine roundtable on exercise guidelines for cancer survivors","volume":"42","author":"Schmitz","year":"2010","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"225","DOI":"10.1519\/JSC.0000000000001890","article-title":"Changes in Unilateral Upper Limb Muscular Strength and Electromyographic Activity after a 16-Week Strength Training Intervention in Survivors of Breast Cancer","volume":"33","author":"Hagstrom","year":"2019","journal-title":"J. Strength Cond. Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e19834","DOI":"10.1097\/MD.0000000000019834","article-title":"Prevalence of postmastectomy pain syndrome and associated risk factors: A large single-institution cohort study","volume":"99","author":"Gong","year":"2020","journal-title":"Medicine"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"48","DOI":"10.1016\/j.jpra.2024.07.021","article-title":"Neuropathic Pain Following Breast-conserving Surgery: A Systematic Review and Meta-Analysis","volume":"42","author":"Kwee","year":"2024","journal-title":"JPRAS Open"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1007\/s10549-024-07381-z","article-title":"Choosing breast-conserving therapy or mastectomy and subpectoral implant breast reconstruction: Implications for pectoralis major function","volume":"207","author":"Leonardis","year":"2024","journal-title":"Breast Cancer Res. Treat."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"914","DOI":"10.1152\/jn.00081.2022","article-title":"Assessing shoulder muscle stretch reflexes following breast cancer treatment and postmastectomy breast reconstruction","volume":"129","author":"Leonardis","year":"2023","journal-title":"J. Neurophysiol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"110348","DOI":"10.1016\/j.jbiomech.2021.110348","article-title":"Neuromuscular compensation strategies adopted at the shoulder following bilateral subpectoral implant breast reconstruction","volume":"120","author":"Leonardis","year":"2021","journal-title":"J. Biomech."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2071","DOI":"10.1111\/sms.14027","article-title":"Changes in EMG and movement velocity during a set to failure against different loads in the bench press exercise","volume":"31","author":"Tsoukos","year":"2021","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_18","first-page":"114","article-title":"Unilateral Resistance Training Can Be Tailored Using Lifting Velocity in Breast Cancer Patients","volume":"47","year":"2025","journal-title":"Int. J. Sports Med."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1023","DOI":"10.1016\/j.jelekin.2010.07.004","article-title":"How should we normalize electromyograms obtained from healthy participants? What we have learned from over 25years of research","volume":"20","author":"Burden","year":"2010","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1016\/j.jelekin.2011.11.009","article-title":"Evaluation of electromyography normalisation methods for the back squat","volume":"22","author":"Balshaw","year":"2012","journal-title":"J. Electromyogr. Kinesiol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"111029","DOI":"10.1016\/j.jbiomech.2022.111029","article-title":"Evidence for the use of dynamic maximum normalization method of muscle activation during weighted back squats","volume":"135","author":"Maddox","year":"2022","journal-title":"J. Biomech."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"600","DOI":"10.1123\/jab.29.5.600","article-title":"Electromyography normalization methods for high-velocity muscle actions: Review and recommendations","volume":"29","author":"Ball","year":"2013","journal-title":"J. Appl. Biomech."},{"key":"ref_23","first-page":"41","article-title":"Examining Unilateral and Bilateral Exercises through the Load-velocity Relationship","volume":"45","year":"2023","journal-title":"Int. J. Sports Med."},{"key":"ref_24","first-page":"110","article-title":"Load-velocity Relationship of the Bench Press Exercise is not Affected by Breast Cancer Surgery and Adjuvant Therapy","volume":"45","author":"Borrego","year":"2023","journal-title":"Int. J. Sports Med."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1055\/s-0029-1242815","article-title":"Importance of the propulsive phase in strength assessment","volume":"31","author":"Perez","year":"2010","journal-title":"Int. J. Sports Med."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1047","DOI":"10.1055\/a-1171-2287","article-title":"Validity of Using Velocity to Estimate Intensity in Resistance Exercises in Men and Women","volume":"41","author":"Walker","year":"2020","journal-title":"Int. J. Sports Med."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"578","DOI":"10.1519\/SSC.0000000000000905","article-title":"Practical Methods for Strength Evaluation in Oncology Patients","volume":"47","year":"2025","journal-title":"Strength Cond. J."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Mart\u00ednez-Cava, A., Hern\u00e1ndez-Belmonte, A., Courel-Ib\u00e1\u00f1ez, J., Mor\u00e1n-Navarro, R., Gonz\u00e1lez-Badillo, J.J., and Pallar\u00e9s, J.G. (2020). Reliability of technologies to measure the barbell velocity: Implications for monitoring resistance training. PLoS ONE, 15.","DOI":"10.1371\/journal.pone.0236073"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"2992","DOI":"10.1519\/JSC.0000000000004060","article-title":"Level of Effort: A Reliable and Practical Alternative to the Velocity-Based Approach for Monitoring Resistance Training","volume":"36","year":"2022","journal-title":"J. Strength Cond. Res."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2139","DOI":"10.1519\/JSC.0000000000002629","article-title":"Effort index as a novel variable for monitoring the level of effort during resistance exercises","volume":"32","author":"Marques","year":"2018","journal-title":"J. Strength Cond. Res."},{"key":"ref_31","unstructured":"Criswell, E. (2010). Cram\u2019s Introduction to Surface Electromyography, Jones & Bartlett Publishers."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"1621","DOI":"10.1111\/sms.13967","article-title":"Effect of velocity loss during squat training on neuromuscular performance","volume":"31","year":"2021","journal-title":"Scand. J. Med. Sci. Sports"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"4222","DOI":"10.1038\/s41467-020-17820-2","article-title":"Tissue sodium excess is not hypertonic and reflects extracellular volume expansion","volume":"11","author":"Rossitto","year":"2020","journal-title":"Nat. Commun."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1098","DOI":"10.70252\/CUZQ3183","article-title":"The Influence of Normalization Technique on Between-Muscle Activation during a Back-Squat","volume":"13","author":"Korak","year":"2020","journal-title":"Int. J. Exerc. Sci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1002\/mus.21981","article-title":"Effect of knee position on quadriceps muscle force steadiness and activation strategies","volume":"43","author":"Krishnan","year":"2011","journal-title":"Muscle Nerve"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1668","DOI":"10.1249\/MSS.0000000000001273","article-title":"Effect of knee joint angle and contraction intensity on hamstrings coactivation","volume":"49","author":"Wu","year":"2017","journal-title":"Med. Sci. Sports Exerc."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1445","DOI":"10.1152\/jappl.1999.86.5.1445","article-title":"Length dependence of active force production in skeletal muscle","volume":"86","author":"Rassier","year":"1999","journal-title":"J. Appl. Physiol."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"1805","DOI":"10.1519\/JSC.0b013e3182577067","article-title":"A biomechanical comparison of the traditional squat, powerlifting squat, and box squat","volume":"26","author":"Swinton","year":"2012","journal-title":"J. Strength Cond. Res."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1372","DOI":"10.1519\/JSC.0000000000002915","article-title":"Resistance Training Performed to Failure or Not to Failure Results in Similar Total Volume, but with Different Fatigue and Discomfort Levels","volume":"35","author":"Vieira","year":"2021","journal-title":"J. Strength Cond. Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1007\/s40279-022-01754-4","article-title":"The Acute and Chronic Effects of Implementing Velocity Loss Thresholds During Resistance Training: A Systematic Review, Meta-Analysis, and Critical Evaluation of the Literature","volume":"53","author":"Jukic","year":"2023","journal-title":"Sports Med."},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Hern\u00e1ndez-Belmonte, A., and Pallar\u00e9s, J.G. (2022). Effects of Velocity Loss Threshold during Resistance Training on Strength and Athletic Adaptations: A Systematic Review with Meta-Analysis. Appl. 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