Investigation of University Level Volleyball Players in Terms of Ankle Functions and Postural Control Variables
Condition: Volleyball; Ankle; Postural Balance
Study type: Observational

Summary: 
      In this study, it is aimed to evaluate different ankle functions and postural control
      variables in university level volleyball players and students with stable ankles and to
      examine the results obtained. In this way, we aim to contribute to the physiotherapy and
      rehabilitation literature and clinical studies of physiotherapists who are interested in
      athlete health.

      The hypothesis set in this study is:

      H0: There is no difference between ankle functions and postural control variables of
      volleyball players and healthy controls.

      H1: There is a difference between ankle functions and postural control variables of
      volleyball players and healthy controls.
    

Detailed description: 
      There are studies proving that athletes with poor postural control have a higher risk of
      injury to the ankle and knee regions than those with normal. Balanced stance and effective
      postural control in activities involving ball contact during the game are the basic skills of
      volleyball. The ankle is a joint that needs to be evaluated frequently and its functions
      should be improved both in order to improve postural control ability and to prevent possible
      injuries. It has been proven in studies that the capacity shown in different functional
      parameters such as joint range of motion, strength and proprioception and balance both
      reduces the risk of injury and positively reflects on the performance parameters of the
      athlete. It will be useful to evaluate and examine the ankle functions and postural controls
      that change as a result of the training and exercises performed by the athletes, unlike
      healthy individuals who are not athletes, in order to understand the abilities developed
      specifically for the sport.

      The study will be carried out in Yeditepe University Physiotherapy and Rehabilitation
      Graduate Laboratory. Female individuals aged 18-25 years, with stable ankles will be included
      in the study as a sample. The study will consist of two groups. The first group will include
      volleyball players playing in university teams, and healthy university students meeting the
      same criteria in the control group. The sample size of the study was calculated using the
      GPower program as type 1 error value= 0.05, power = 0.90, effect size (f value) calculated
      from the reference article and total of 40 subjects for the independent sample t-test.

      The Cumberland Ankle Instability Tool will be used to select suitable participants for the
      study. Only ankles considered stable according to the questionnaire will be included in this
      study. First, static balance will be evaluated with the PK Prokin 252 system during the
      silent stand for postural control assessment. Then, different ankle functions of the people
      who will participate in the study will be evaluated. The measurement of the range of motion
      of the ankle will be evaluated with the help of a goniometer. Different degrees of position
      sense of the ankle joint will be evaluated with the aid of a goniometer and the sense of
      vibration will be evaluated with a tuning fork. Muscle strength will be measured with the
      help of a manual dynamometer during the movements of the muscles around the ankle. In
      addition, the participants who volunteered to participate in the study before the tests will
      be given a Voluntary Consent Form and a Demographic Information Form. Participants will be
      given rest periods between each test. Evaluation time will be 45 minutes for each
      participant. Participants will not be followed up after the assessments.
    

Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Non-Probability Sample
Study population: 
        The study was carried out with female individuals aged 18-25 who have stable ankles and
        have not had an ankle injury in the last 1 year. The study includes volleyball players
        playing in university teams and healthy university students who meet the same criteria.
      
Keywords: postural control; ankle; range of motion; strenght; vibration; proprioception; volleyball