ArticleSports health
Conditioning Brain Responses to Improve Quadriceps Function in an Individual With Anterior Cruciate Ligament Reconstruction.
Article in Sports health. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 10 papers, 1 of them a synthesis that pooled it.
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Who cites it
10 citing papers in PubMed, 1 synthesis or guideline pooled it, 19 citations in OpenAlex.
- Assessment of Quadriceps Corticomotor and Spinal-Reflexive Excitability in Individuals with a History of Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis.Sports medicine (Auckland, N.Z.) · 2021Pooled it
- Number of conditioning trials, but not stimulus intensity, influences operant conditioning of brain responses after total knee arthroplasty.Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA · 2025Trial
- Dynamic change of direction, isometric strength, and psychological readiness in final phase ACLR athletes: an integrated approach.BMC musculoskeletal disorders · 2025Article
- Effects of Low-Load Blood Flow Restriction Training on Muscle Volume After Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis.Orthopaedic journal of sports medicine · 2024Review
- Biomarkers for rapid H-reflex operant conditioning among females.Journal of neurophysiology · 2023Article
- Functional Resistance Training to Improve Knee Strength and Function After Acute Anterior Cruciate Ligament Reconstruction: A Case Study.Sports health · 2021Article
- Evaluation of motor cortical excitability using evoked torque responses: A new tool with high reliability.Journal of neuroscience methods · 2021Article
- Effect of conventional transcranial direct current stimulation devices and electrode sizes on motor cortical excitability of the quadriceps muscle.Restorative neurology and neuroscience · 2021Article
- The Missing Link.Sports healthArticle
- Making Progress.Sports healthArticle
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Authors and funding
6 authors at 2 institutions in 2 countries.
Funding
Abstract
backgroundPersistent quadriceps weakness and activation failure are common in individuals with anterior cruciate ligament (ACL) reconstruction. A growing body of evidence indicates that this chronic quadriceps dysfunction could be partly mediated due to reduced corticospinal excitability. However, current rehabilitation approaches do not directly target corticospinal deficits, which may be critical for restoring optimal clinical outcomes after the surgery. This case study tested the feasibility of operant conditioning of torque responses evoked by transcranial magnetic stimulation (TMS) to improve quadriceps function after ACL reconstruction. HYPOTHESIS: Operant conditioning of motor evoked torque responses would improve quadriceps strength, voluntary activation, and corticospinal excitability. STUDY
designCase study and research report. LEVEL OF EVIDENCE: Level 5.
methodsA 24-year-old male with an ACL reconstruction (6 months postsurgery) trained for 20 sessions (2-3 times per week for 8 weeks) to increase his TMS-induced motor evoked torque response (MEP torque) of the quadriceps muscles using operant conditioning principles. Knee extensor strength, voluntary quadriceps muscle activation, and quadriceps corticospinal excitability were evaluated at 3 time points: preintervention (pre), 4 weeks (mid), and immediately after the intervention (post).
resultsThe participant was able to successfully condition (ie, increase) the quadriceps MEP torque after 1 training session, and the conditioned MEP torque gradually increased over the course of 20 training sessions to reach about 500% of the initial value at the end of training. The participant's control MEP torque values and corticospinal excitability, which were measured outside of the conditioning paradigm, also increased with training. These changes were paralleled by improvements in knee extensor strength and voluntary quadriceps muscle activation.
conclusionThis study shows that operant conditioning of MEP torque is a feasible approach to improving quadriceps corticospinal excitability and quadriceps function after ACL reconstruction and encourages further testing in a larger cohort of ACL-reconstructed individuals. CLINICAL RELEVANCE: Operant conditioning may serve as a potential therapeutic adjuvant for ACL rehabilitation.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.