Load-dependent impairments in fibularis longus neural drive and motor unit rate coding.
Dr Michail Arvanitidis
Centre of Precision Rehabilitation for Spinal Pain
School of Sport, Exercise and Rehabilitation Sciences
University of Birmingham, United Kingdom
Google Scholar 378 citations 11 h-index 11 i10-index as of Oct 2026
Research
Dr Michail Arvanitidis (PT, PhD, MSc, MMACP) is a Postdoctoral Research Fellow at the Centre of Precision Rehabilitation for Spinal Pain (CPR Spine), School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, United Kingdom. His current research examines cervical adaptations in NASA astronauts following spaceflight, aiming to enhance astronaut health for future missions. His main interests involve studying motor adaptations in pain-affected or vulnerable populations.
Methods and tools
A grid of 64 electrodes over a muscle records activity at every point, so the map shows where the muscle is working hardest. Move across the grid to shift that activity. Changes in this spatial distribution are one way muscles adapt to pain, and a recurring focus of this research.
Simulated signal, for illustration.
Each row is one motor unit: a nerve cell and the muscle fibres it drives, as identified from high-density EMG. Raise the force to recruit more units and make them fire faster. Switch on pain to see the pattern reported in people with pain: slower, less regular firing and a less steady force.
Simulated, for illustration. Sound plays each discharge as a note.
Houston, Texas
Houston, Texas
The 3D model needs WebGL, which this browser has turned off.
The cervical spine: seven vertebrae, C1 to C7, separated by discs (teal) and held in a gentle forward curve by the deep neck muscles (red).
Without gravity to compress it, the spine lengthens. The discs take on fluid and swell, the neck's curve flattens, and the deep neck muscles, no longer holding up the head, can lose size. The Cervical in Space trial measures these changes in astronauts, and how they relate to the higher risk of disc herniation after flight.
Drag to turn the model. Simplified, with the changes exaggerated for illustration.
Collaborations
All institutions
- Brisbane, Australia The University of Queensland
- Sydney, Australia University of Technology Sydney
- Toowoomba, Australia University of Southern Queensland
- Santiago, Chile Universidad Mayor; Universidad de Los Andes, Chile
- Valparaíso, Chile University of Valparaíso
- Prague, Czechia Charles University
- Helsinki, Finland Finnish Defence Forces
- Aachen, Germany FH Aachen
- Berlin, Germany Charité - Universitätsmedizin Berlin
- Bochum, Germany Hochschule für Gesundheit - University of Applied Sciences
- Cologne, Germany German Sport University Cologne
- Ulm, Germany Universität Ulm
- Athens, Greece University of West Attica
- Lamia, Greece Technological Educational Institute of Central Greece
- Pátrai, Greece University of Patras
- Volos, Greece University of Thessaly
- Hadera, Israel Hillel Yaffe Medical Center
- Haifa, Israel Technion – Israel Institute of Technology
- Brescia, Italy University of Brescia
- Rome, Italy Foro Italico University of Rome; Istituto Nazionale per l'Assicurazione Contro gli Infortuni sul Lavoro; Roma Tre University
- Turin, Italy Politecnico di Torino; University of Turin
- Differdange, Luxembourg LUNEX; Luxembourg Health & Sport Sciences Research Institute
- Gothenburg, Sweden Sahlgrenska University Hospital
- Manno, Switzerland University of Applied Sciences and Arts of Southern Switzerland
- Amsterdam, The Netherlands Vrije Universiteit Amsterdam
- Groningen, The Netherlands Martini Ziekenhuis
- Leiden, The Netherlands Leiden University; Leiden University Medical Center
- Rotterdam, The Netherlands Maasstad Ziekenhuis
- Leeds, United Kingdom Leeds Beckett University
- Liverpool, United Kingdom Liverpool University Hospitals NHS Foundation Trust; University of Liverpool
- London, United Kingdom Imperial College London
- Manchester, United Kingdom Manchester Metropolitan University; University of Manchester
- Newcastle-under-Lyme, United Kingdom Keele University
- Houston, United States Johnson Space Center
Positions
Project: Cervical in Space — cervical spine and muscle adaptation after spaceflight and relationship to herniation risk. Mentor: Prof. Deborah Falla.
Data collection, analysis and dissemination for the Cervical in Space programme alongside doctoral studies.
Astronaut neck strength and neuromuscular assessment protocols; HD-sEMG and dynamometry pipeline development.
Part-time clinical practice. Assessment and management of complex spinal and musculoskeletal presentations. Employer: Dr David W. Evans.
Outpatient musculoskeletal and post-surgical rehabilitation.
Education
Control of trunk muscle force in chronic low back pain, using high-density surface EMG and isokinetic dynamometry. Supervisors: Dr Eduardo Martinez-Valdes, Prof. Deborah Falla.
MMACP-accredited programme. Supervisors: Dr Eduardo Martinez-Valdes, Prof. Deborah Falla.
Supervisor: Prof. Georgios Gioftsos. Honorary fellowship, National Scholarships Foundation (2011–12).
Publications 29 published · 7 in progress
Under review & in preparation
Similar clinical improvements but distinct neuromechanical adaptations between training modes.
Greater dynamic trunk extensor fatigue resistance in older adults despite poorer torque steadiness.
Non-invasive HD-sEMG approach to estimate erector spinae muscle fibre size.
First synthesis showing neck-specific exercise may induce structural cervical muscle adaptation.
AR HD-sEMG biofeedback modified spatial muscle activation and improved knee extensor endurance by 27%.
2026
Simultaneous HD-sEMG and ultrasound via transparent electrodes revealed contraction-dependent neuromechanical coupling.
Novel insight into neuromuscular impairments in patellofemoral pain during single-joint exercise.
Age-related impairments in trunk force control with distinct HD-sEMG patterns.
Updated diagnostic accuracy evidence informing evidence-based clinical decision-making.
Revealed regional differences in lumbar erector spinae activity in people with spinal pain.
First demonstration of load- and muscle-dependent motor unit changes in Achilles tendinopathy.
Adaptive redistribution of neck muscle activity during experimentally induced soreness.
First meta-analysis showing reduced trunk muscle endurance in older adults.
2025
Force steadiness is impaired in musculoskeletal pain — a candidate rehabilitation target.
The NOD is a valid, reliable, portable alternative to laboratory dynamometry.
Will inform countermeasures to reduce spinal pain and injury risk in astronauts.
First evidence of age-related differences in spatial lumbar activation under fatigue.
First trial of torque-based visual feedback training for patellar tendinopathy.
2024
First study of how DOMS influences trunk HD-sEMG–torque relationships and lumbar kinematics.
First evidence of impaired torque steadiness and altered HD-sEMG–torque relationships in dynamic trunk contractions in CLBP.
Novel link between motor unit firing behaviour and Achilles tendon mechanical properties.
New HD-sEMG spatial metrics that characterise fatigue and predict muscle endurance.
2023
2022
Novel HD-sEMG approach overcoming decomposition challenges in the lumbar erector spinae.
International project on cervical spine adaptation after spaceflight and preventive strategies for astronauts.
2021
Altered, potentially less efficient lumbar erector spinae activation during dynamic fatigue in CLBP.
HD-sEMG discriminates biomechanical risk earlier and more accurately than traditional sEMG.
Pain affects motor unit behaviour differently across contraction speeds.
2019
First study to test whether humans can selectively modify trapezius activity using HD-sEMG visual feedback.
2016
Awards
Funding
Conference presentations 13 oral · 9 poster
Refereed conference proceedings. An asterisk marks the presenter.
Oral — 13 presentations
Poster — 9 presentations
Teaching and mentoring
Service
CPR Spine, University of Birmingham
Journal peer review
Registration and membership
- 01Association of Chartered Physiotherapists in Occupational Health and Ergonomics2026
- 02International Society of Electrophysiology and Kinesiology2020
- 03Musculoskeletal Association of Chartered Physiotherapists2019
- 04Health and Care Professions Council (HCPC)2018
- 05Chartered Society of Physiotherapy2018
- 06Panhellenic Association of Physiotherapists2016
Certification and training
- 01Vehicle ErgonomicsACPOHE2026
- 02Office Ergonomics (DSE)ACPOHE2026
- 03Supervised Machine Learning: Regression and ClassificationDeepLearning.AI and Stanford Online2025
- 04R ProgrammingJohns Hopkins University2024
- 05The Data Scientist's ToolboxJohns Hopkins University2023
- 06Certified Peer Reviewer CourseElsevier2021
- 07Introduction to Programming with MATLABVanderbilt University2019
- 08Otago Exercise Programme Leader AwardLater Life Training2015