title: The effect of repetitive ankle perturbations on muscle reaction time and muscle activity.
abstract: The use of a tilt platform to simulate a lateral ankle sprain and record muscle reaction time is a well-established procedure. However, a potential caveat is that repetitive ankle perturbation may cause a natural attenuation of the reflex latency and amplitude. This is an important area to investigate as many researchers examine the effect of an intervention on muscle reaction time. Muscle reaction time, peak and average amplitude of the peroneus longus and tibialis anterior in response to a simulated lateral ankle sprain (combined inversion and plantar flexion movement) were calculated in twenty-two physically active participants. The 40 perturbations were divided into 4 even groups of 10 dominant limb perturbations. Within-participants repeated measures analysis of variance (ANOVA) tests were conducted to assess the effect of habituation over time for each variable. There was a significant reduction in the peroneus longus average amplitude between the aggregated first and last 10 consecutive ankle perturbations (F2.15,45.09=3.90, P=0.03, ɳp(2)=0.16). Authors should implement no more than a maximum of 30 consecutive ankle perturbations (inclusive of practice perturbations) in future protocols simulating a lateral ankle sprain in an effort to avoid significant attenuation of muscle activity.
authors.affiliation: Faculty of Health, Education and Life Sciences, Birmingham City University, Birmingham, United Kingdom; School of Life and Medical Sciences, University of Hertfordshire, Hatfield, United Kingdom. Electronic address: peter.thain@hotmail.co.uk.
authors.forename: Peter Kevin
authors.initials: PK
authors.lastname: Thain
authors.affiliation: Department of Kinesiology, University of San Francisco, CA, United States.
authors.forename: Gerwyn Trefor Gareth
authors.initials: GT
authors.lastname: Hughes
authors.affiliation: School of Sport Science & Physical Activity, University of Bedfordshire, Bedford, United Kingdom.
authors.forename: Andrew Charles Stephen
authors.initials: AC
authors.lastname: Mitchell
mesh_terms: D000704:Analysis of Variance; D000842:Ankle / Q000502:physiology*; D016512:Ankle Injuries / Q000503:physiopathology; D000843:Ankle Joint / Q000502:physiology; D001696:Biomechanical Phenomena; D004576:Electromyography; D005260:Female; D005528:Foot / Q000502:physiology; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology; D008297:Male; D009068:Movement; D018482:Muscle, Skeletal / Q000502:physiology*; D011930:Reaction Time; D055815:Young Adult
keywords: Ankle sprain; Habituation; Reaction time; Tilt platform