title: An isokinetic method for inducing a localised fatigue effect in the plantarflexors and dorsiflexors of the ankle.
abstract: To examine the effects of dysfunction of specific musculature of the shank a reliable and valid protocol can be used to induce a localised fatigue effect. A localised dynamometry based protocol was developed to illicit a fatigue effect in either plantar flexors or dorsiflexors. An isokinetic protocol allowing for movement through the full range of motion, set at an angular velocity of 45°s(-1), was used to allow fatigue to be developed. Fatigue was established when three consecutive torque measures dropped below 50% of the average three peak contractions. Bouts of activity were based on a ratio of 40 contractions interspaced with a 30s rest. Results suggest that the protocol elicited a fatigue effect in the prime movers of either plantar flexion or dorsiflexion, supported through the analysis of power spectral density and amplitude shift of surface electromyography measures. The protocol demonstrated sound reliability with Interclass Correlation scores for all measures ranging from 0.441-0.962. The protocol is a valid and repeatable process for establishing muscular weakness in the working muscles of either plantar or dorsi flexion, as observed in the fatigued state. This can allow further examination of the effects of a localised muscular weakness on daily living tasks.
authors.affiliation: School of Life Science, Faculty of Science, Engineering and Computing, Kingston University, London, UK. Electronic address: james.brouner@kingston.ac.uk.
authors.forename: James
authors.initials: J
authors.lastname: Brouner
authors.affiliation: Faculty of Health Science and Education, Kingston University/St George's University of London, UK.
authors.forename: Gita
authors.initials: G
authors.lastname: Ramdharry
authors.affiliation: School of Life Science, Faculty of Science, Engineering and Computing, Kingston University, London, UK.
authors.forename: Nicola
authors.initials: N
authors.lastname: Swann
mesh_terms: D000328:Adult; D000842:Ankle / Q000502:physiology; D000843:Ankle Joint / Q000502:physiology*; D004576:Electromyography / Q000379:methods*; D006801:Humans; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology*; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology; D015203:Reproducibility of Results; D055815:Young Adult
keywords: Dynamometry; Muscular dysfunction; Repeatable protocol