Within-session acquisition of anticipatory postural adjustments during forward reaching task

Clin Neurol Neurosurg. 2015 Feb:129 Suppl 1:S53-7. doi: 10.1016/S0303-8467(15)30013-5.

Abstract

Objective: To describe the acquisition of anticipatory postural adjustment (APA) in healthy adults during standing forward reaching.

Design: Repeated-measures design Subjects/Patients: Ten healthy subjects.

Methods: Within one day, all subjects practiced forward reaching to a moving target for sixty trials (10 trials, 6 blocks). APAs were recorded by electromyography (EMG), center of pressure (COP), and kinematic measurements. Repeated measure ANOVA was used to compare the changes of APA among the six blocks.

Results: All subjects showed basic APA patterns in the beginning, such as posterior shift of COP and tibialis anterior firing first. The adults demonstrated significantly quicker onset of posterior shift of COP between block 2 and 6 (p<0.05) and decreased muscle activation of ispilateral tibialis anterior between block 1 and 3 (p=0.01).

Conclusions: The results suggested the acquisition process of APA could be observed after 50 trials of practice. Further study will need to verify the optimal practice trials in different populations with movement disorders.

Keywords: Anticipatory postural adjustments; Forward reaching; Healthy adult; Within-session acquisition.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological / physiology*
  • Arm
  • Biomechanical Phenomena
  • Electromyography
  • Female
  • Healthy Volunteers
  • Humans
  • Male
  • Movement / physiology*
  • Muscle Contraction / physiology*
  • Muscle, Skeletal / physiology*
  • Postural Balance / physiology*
  • Posture
  • Young Adult