Immediate Effects of Whole Body Vibration on Neuromuscular Performance of Quadriceps Femoris and Balance
Condition: Neuromuscular Performance and Balance
Study type: Interventional

Summary: 
      The purpose of this study is to analyze the immediate effects of two exercise protocols on
      the vibration platform, on the strength of the thigh muscles, joint position sense of the
      knee and balance in healthy subjects.
    

Detailed description: 
      Design and research site: This is a randomized and blinded clinical trial held at the
      Laboratory of Neuromuscular Performance of the Department of Physical Therapy, Federal
      University of Rio Grande do Norte (UFRN). Characterization of the sample: The sample
      consisted of 60 women randomly divided into 3 distinct groups. Ethical aspects: For its
      implementation, this project was submitted to the Research Ethics Committee (REC) of the
      Federal University of Rio Grande do Norte. Was respected and ensured the autonomy and
      anonymity of participants, as well as your privacy as confidential data, as governed
      Resolution 196/96 of the National Health Council and the Helsinki declaration for human
      research. Instruments: Stationary bicycle (Ergo-Fit, ErgoCycle 167, Pirmasens, Germany);
      computerized baropodometry platform Eclipse 3000 model (Guy-Capron® SA, France); vibrating
      platform model Power Plate® pro5 ™; signal conditioning module (Telemyo direct transmission
      system) 8-channel (Noraxon, USA); self-adhesive electrode active surface (Noraxon, USA);
      isokinetic dynamometer (Biodex Multi-Joint System 4, Biomedical Biodex System Inc.®, New
      York, USA). Procedures: There was a previous pilot study for adequacy of any research
      procedures and the training of evaluators. The volunteers were informed about the procedures
      to be performed in the research, signed the informed consent form, fill in an evaluation form
      with anthropometric data and personal examination of members. Evaluations were performed
      before and after the intervention protocol. Initially, all the volunteers executed a warming
      exercise on a stationary bike for 5 minutes. Postural balance: the volunteers were placed
      standing on the baropodometry platform, supported in the non-dominant member and with the
      knee kept at 20 ° of flexion. The dominant member remained with the knee in 90 ° of flexion.
      The evaluation was repeated 3 times, being considered for analysis the average of the two
      best measures. The evaluation time was 20 seconds on an acquisition frequency of 20 Hz with a
      period of 1 minute break between tests. Previously the participant was allowed to become
      familiar with the equipment. Joint position sense: the volunteer was positioned sitting on
      the dynamometer, stabilized by braces and with the device axis aligned with the knee
      evaluated. The apparatus of the lever arm was attached to the distal leg. Then, the volunteer
      was instructed to perform a knee extension member starting with 90 ° of flexion. When the 45
      target angle wass reached, the dynamometer arm remained in this position, keeping it for 5
      seconds, so that the voluntary noticed which the angle to be achieved. Finally, prompted an
      active extension from 90 ° knee flexion (1 / s) to the target angle, the second trial of the
      subject. At that moment, the volunteer should trigger a device to record the angle reached.
      Torque rating: keeping the same previous position, the normalization of the electromyographic
      signal was held, where the subject performed two maximal voluntary isometric contractions of
      knee extension at an angle of 60 ° for 5s, with one-minute interval between each repetition.
      Then the concentric evaluation was conducted, with 5 maximal contractions for knee flexion
      and extension at 60 ° / s, starting from 90 ° flexion up to full extension. Electromyographic
      activity: emg was collected concurrently with exercise protocols on the platform, as well as
      during the torque rating. The volunteers were submitted for shaving and cleaning the skin
      with 70% alcohol before attaching the electrodes.
    

Intervention name(s): Vibration at 30 Hz; Vibration at 50 Hz
Intervention type(s): Other; Other
Intervention description(s): During the exercise protocol, the vibration platform will be turned on at a vibration frequency of 30 Hz.; During the exercise protocol, the vibration platform will be turned on at a vibration frequency of 50 Hz.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: Postural Balance; Electromyography; Torque