title: Skin Cooling and Force Replication at the Ankle in Healthy Individuals: A Crossover Randomized Controlled Trial.
abstract: BACKGROUND
  Proprioception of the ankle is determined by the ability to perceive the sense of position of the ankle structures, as well as the speed and direction of movement. Few researchers have investigated proprioception by force-replication ability and particularly after skin cooling.
  
  
  OBJECTIVE
  To analyze the ability of the ankle-dorsiflexor muscles to replicate isometric force after a period of skin cooling.
  
  
  METHODS
  Randomized controlled clinical trial.
  
  
  METHODS
  Laboratory.
  
  
  METHODS
  Twenty healthy individuals (10 men, 10 women; age = 26.8 ± 5.2 years, height = 171 ± 7 cm, mass = 66.8 ± 10.5 kg).
  
  
  METHODS
  Skin cooling was carried out using 2 ice applications: (1) after maximal voluntary isometric contraction (MVIC) performance and before data collection for the first target force, maintained for 20 minutes; and (2) before data collection for the second target force, maintained for 10 minutes. We measured skin temperature before and after ice applications to ensure skin cooling.
  
  
  METHODS
  A load cell was placed under an inclined board for data collection, and 10 attempts of force replication were carried out for 2 values of MVIC (20%, 50%) in each condition (ice, no ice). We assessed force sense with absolute and root mean square errors (the difference between the force developed by the dorsiflexors and the target force measured with the raw data and after root mean square analysis, respectively) and variable error (the variance around the mean absolute error score). A repeated-measures multivariate analysis of variance was used for statistical analysis.
  
  
  RESULTS
  The absolute error was greater for the ice than for the no-ice condition (F1,19 = 9.05, P = .007) and for the target force at 50% of MVIC than at 20% of MVIC (F1,19 = 26.01, P < .001).
  
  
  CONCLUSIONS
  The error was greater in the ice condition and at 50% of MVIC. Skin cooling reduced the proprioceptive ability of the ankle-dorsiflexor muscles to replicate isometric force.
authors.affiliation: Center of Health and Sports Sciences, University of the State of Santa Catarina, Brazil;
authors.forename: Daniela Pacheco dos Santos
authors.initials: DP
authors.lastname: Haupenthal
authors.affiliation: Center of Health and Sports Sciences, University of the State of Santa Catarina, Brazil;|Rural Health School, La Trobe University, Victoria, Australia.
authors.forename: Marcos
authors.initials: M
authors.lastname: de Noronha
authors.affiliation: Center of Health and Sports Sciences, University of the State of Santa Catarina, Brazil;
authors.forename: Alessandro
authors.initials: A
authors.lastname: Haupenthal
authors.affiliation: Center of Health and Sports Sciences, University of the State of Santa Catarina, Brazil;
authors.forename: Caroline
authors.initials: C
authors.lastname: Ruschel
authors.affiliation: Center of Health and Sports Sciences, University of the State of Santa Catarina, Brazil;
authors.forename: Guilherme S
authors.initials: GS
authors.lastname: Nunes
mesh_terms: D000328:Adult; D000843:Ankle Joint / Q000502:physiology*; D001696:Biomechanical Phenomena / Q000502:physiology; D003080:Cold Temperature; D018592:Cross-Over Studies; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007053:Ice; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology*; D011434:Proprioception / Q000502:physiology*; D012881:Skin Temperature / Q000502:physiology; D013639:Tarsal Bones / Q000502:physiology
chemical_list: D007053:Ice
keywords: cryotherapy; isometric force; proprioception