An acoustic myography functional assessment of cerebral palsy subjects compared to healthy controls during physical exercise

  • Jessica PingelEmail author
  • Ida Torp Andersen
  • Rikke Broholm
  • Anja Harder
  • Else Marie Bartels
  • Jens Bülow
  • Adrian Harrison
Original Article


Individuals with cerebral palsy (CP) participate in reduced levels of physical activity and spend an increased amount of time in a sedentary state compared with healthy control subjects. Whether this in part can be explained by impaired muscle function is still unclear. The aim of the present study was to elucidate differences in muscle fibre recruitment during treadmill exercise between CP subjects and healthy age-, sex- and BMI-matched controls. This is a case–control study. Acoustic myography (AMG), a method recording fibre use and efficiency from contracting muscles, was applied during a period of treadmill exercise. The recorded AMG parameters revealed that the CP subjects had a significantly lower initial S-score (spatial summation) than the controls (P < 0.01). However, the T-score (temporal summation) and the E-score (efficiency) showed no significant differences between individuals with CP and the healthy control subjects. The present findings indicate that CP subjects use a higher degree of spatial summation (more fibres recruited) to keep up the same speed during treadmill exercise when compared to healthy matched control subjects. Our results suggest that individuals with CP have a tendency to recruit far more muscle fibres during bouts of exercise than healthy individuals. This may partly explain why CP subjects experience premature fatigue.


Cerebral palsy Muscle fatigue Muscle fibre activity Acoustic myography 



We gratefully thank Bente Matthiesen for all her professionalism both with the practical and the administrative aspects of this clinical setup.


This project was funded by the Danish research Council (DFF-1333-00197), and the Elsass Foundation.

Compliance with ethical standards

Conflict of interest

All the authors declare that they have no conflict of interest in the present study.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Department of NeuroscienceCopenhagen UniversityCopenhagenDenmark
  2. 2.Department of Clinical Physiology and Nuclear MedicineBispebjerg and Frederiksberg HospitalCopenhagenDenmark
  3. 3.Department of Clinical Physiology and Nuclear MedicineHerlev and Gentofte HospitalCopenhagenDenmark
  4. 4.Section for Pathobiological Sciences, Faculty of Health & Medical SciencesCopenhagen UniversityFrederiksbergDenmark
  5. 5.Department of Neurology and the Parker InstituteBispebjerg and Frederiksberg HospitalCopenhagenDenmark
  6. 6.Department of Biomedical SciencesCopenhagen UniversityCopenhagenDenmark

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