title: Assessment of the activation modalities of gastrocnemius lateralis and tibialis anterior during gait: a statistical analysis.
abstract: Aim of the study was to identify the different modalities of activation of gastrocnemius lateralis (GL) and tibialis anterior (TA) during gait at self-selected speed, by a statistical analysis of surface electromyographic signal from a large number (hundreds) of strides per subject. The analysis on fourteen healthy adults showed a large variability in the number of activation intervals, in their occurrence rate, and in the on-off instants, within different strides of the same walk. For each muscle, the assessment of the different modalities of activation (five for muscle) allowed to identify a single pattern, common for all the modalities and able to characterize the behavior of muscles during normal gait. The pattern of GL activity centered in two regions of the gait cycle: the transition between flat foot contact and push-off (observed in 100% of total strides) and the final swing (67.1 ± 15.9%). Two regions characterized also the pattern of TA activity: from pre-swing to following loading response (100%), and the mid-stance (30.5 ± 15.0%). This "normality" pattern represents the first attempt for the development in healthy young adults of a reference for dynamic EMG activity of GL and TA, in terms of variability of on-off muscular activity and occurrence rate during gait.
authors.affiliation: Department of Information Engineering, Università Politecnica delle Marche, 60131 Ancona, Italy. Electronic address: f.dinardo@univpm.it.
authors.forename: Francesco
authors.initials: F
authors.lastname: Di Nardo
authors.forename: Giacomo
authors.initials: G
authors.lastname: Ghetti
authors.forename: Sandro
authors.initials: S
authors.lastname: Fioretti
mesh_terms: D000328:Adult; D000842:Ankle / Q000502:physiology; D004576:Electromyography; D005260:Female; D005684:Gait / Q000502:physiology*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D055815:Young Adult
keywords: Ankle flexor muscles; EMG; Gait analysis