We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Effect of forward and backward sloped support surfaces on postural equilibrium and ankle muscles activity.
- Authors
Atsawakaewmongkhon, Siripatra; Couillandre, Annabelle; Hamaoui, Alain
- Abstract
Introduction: Although sloped surfaces are common in daily living, most studies of body balance are carried out on flat surfaces, and few data are available for sloping angles below 14°. Objectives: The purpose of this study was to explore the effect of forward and backward sloping surfaces at 7° and 15° on postural equilibrium and the activity of flexor/extensor ankle muscles. Methods: Fifteen healthy subjects (8 males and 7 females) (27.67 ± 3.9 years) underwent a posturographic examination associated with a surface electromyogram (EMG) of tibialis anterior (TA), soleus (Sol) and gastrocnemius medialis (GasM) under five conditions of support inclination: 0° (H0), backward inclination at 7° and 15° (DF7 and DF15), forward inclination at 7° and 15° (PF7 and PF15). Results: Results showed that the center of pressure (CP) was shifted according to the surface slope, with a forward move in PF7 (p <0.001) and PF15 (p <0.001) and a backward move in DF7 (p <0.01) and in DF15 (p <0.001). The mean displacement of the CP along the anterior-posterior axis (Xm) was increased in DF15 (p <0.01) relative to the H0 condition but reduced in PF7 (p <0.01). The normalized EMG revealed higher values when the muscles were in a shortened position (PF7 for Sol, p <0.05; PF15 for GasM, p <0.01; DF15 for TA, p<0.01) and lower values of GasM and Sol when lengthened (DF15, p <0.05). Conclusion: Our findings indicate that standing on a backward sloped surface impairs body balance, while low-angle forward sloped surfaces might improve postural stability. Muscular activity variations of the ankle flexors/extensors, which are stretched or shortened, also seem to be related to the length-tension relationship of skeletal muscles.
- Subjects
POSTURAL muscles; ANKLE; EXTENSOR muscles; TIBIALIS anterior; SLOPES (Soil mechanics); SKELETAL muscle; EQUILIBRIUM
- Publication
PLoS ONE, 2024, Vol 19, Issue 6, p1
- ISSN
1932-6203
- Publication type
Article
- DOI
10.1371/journal.pone.0305840