Photobiomodulation in Different Doses on Strength Capacities and Functional Performance
Condition: Low Level Laser Therapy; Performance; Sport
Study type: Interventional

Summary: 
      Background: Photobiomodulation has been explored for years, with wide clinical use for wound
      healing and analgesia in varied orthopedic conditions, but the number of research and
      clinical use has increased during the last decade. Furthermore, considering the performance,
      the current literature is conflicting and restricted, with divergences in wavelength, power
      and energy density applied. Therefore, analyze different doses for a answer in short and long
      time, associated with capacities of strength, fatigue resistance and functional performance
      of handball players and healthy individuals becomes necessary. Objective: To analyze the
      effects of the application of LED photobiomodulation on the capacities of strength,
      functional efficiency, temperature and fatigue resistance of handball players and healthy
      individuals. Method: The study sample will be composed of 56 male individuals randomly
      allocated into four groups: LED 50J (G-50J), LED 240J (G-240J), LED 50-240J (G-50-240J) -
      progressive dose and Sham (G-S). The volunteers will be submitted to an evaluation of muscle
      performance and functional performance, metabolic, and physiological evaluation. After
      initial tests, in five consecutive weeks, the LEDT (940nm - infrared) will be applied to the
      quadriceps femoris muscle and hamstrings, bilaterally, associated with a muscle strength
      protocol. After 24 hours of the last application TLED, the tests will be repeated. Seven days
      after the last intervention will be performed a follow-up. For analysis, normality tests will
      be used to verify the distribution and adequate statistical tests for the appropriate intra
      and intergroup comparisons, being considered two factors in the comparisons, time, and group.
      A significance level of 5% will be adopted.
    

Detailed description: 
      It is a blinded randomized clinical trial. The volunteers will undergo pre-evaluation, 5
      weeks of training associated with the LED application, being distributed in two applications
      per week, and a re-evaluation 24 hours after the last application, totaling a total of
      approximately 7 weeks. Thus, on the first day (Pre-test) volunteers will be submitted to
      anthropometric evaluation and evaluation by bioimpedance for analysis of detailed body
      composition. Then, the maximum voluntary contraction test (CVM) will be performed on the
      isokinetic dynamometer, together with the electromyographic evaluation. Before and after the
      evaluation with the isokinetic dynamometer, thermography will be collected. Still, will be
      evaluated the vertical jump test after 15 minutes of passive rest.

      After the initial evaluations, the researcher will go apply the respective interventions,
      which consist of applying LEDs all over the quadriceps and hamstring bilaterally, while the
      sham group (GS) will receive the LED application off, without the emission of light. The
      application will occur for five weeks and will occur twice weekly, on days spaced for at
      least 48 hours. The same will be done in conjunction with the lower limb strength training
      protocol.

      The tests performed at the time of pre-application of the LED (Pre-test) will be reapplied in
      the same order 24 hours after the last application of the interventions. After seven days of
      the last application, the isokinetic evaluation, electromyography, and vertical jump
      evaluation will be performed. In addition, at the end of the second and fourth weeks, the
      volunteer will carry out an evaluation with the isokinetic dynamometer, electromyography,
      plethysmography, and thermography.
    

Intervention name(s): Photobiomodulation
Intervention type(s): Other
Intervention description(s): An LED blanket with 267 infrared lamps with predetermined doses will be used, given a wavelength of 940nm, for 5 weeks, it will be applied by all extension of the quadriceps and hamstrings bilaterally, just before the force training protocol for the groups intervention or simulation for the sham group. Photochemical or photophysical effects are expected from its application.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Other
Keywords: Isokinetic; Electromyography; Physiotherapy; Athletic Performance