Phototherapy and Cryotherapy in Post-exercise Skeletal Muscle Recovery
Condition: Post-exercise Muscle Recovery
Study type: Interventional

Summary: 
      Volunteers were divided randomly in five experimental groups. VAS (Visual Analogic scale) to
      measure DOMS (Delayed Onset Muscle Soreness) and blood samples was taken before any
      procedure. Then, volunteers performed stretching and warm-up followed by MVC test (isometric
      test in isokinetic dynamometer to measure muscle function). After, volunteers performed the
      exercise protocol (75 eccentric contractions) to lead to muscle fatigue. Immediately after
      exercise protocol (1 minute) and 1 hour, 24, 48, 72 and 96 hours after, blood sample, VAS
      measure and MVC test were repeated. The treatments according to randomisation were performed
      three minutes after exercise protocol and it were performed again in 24, 48, 72h after
      eccentric exercise.

      The variables regarding to muscle function (MVC, DOMS) and the indirect marker of muscle
      damage (CK activity) were monitored in all time points mentioned above (baseline, 1 minute, 1
      hour, 24, 48, 72 and 96 hours after exercise protocol).
    

Detailed description: 
      A randomized, double-blind, placebo-controlled clinical trial was performed at the Laboratory
      of Phototherapy in Sport and Exercise at Nove de Julho University in the city of São Paulo,
      Brazil.

      Fifty healthy untrained male subjects were recruited from university staff and students to
      participate in the study. All participants voluntarily must agree to participate and they
      signed the informed consent statement. The intention-to-treat analysis was followed.

      The volunteers were randomly allocated to five experimental groups (n=10 per group) according
      to the applied comparator. Randomisation was carried out by a simple drawing of lots (A, B,
      C, D or E). Blood samples (10 ml) was taken by a qualified nurse to analyse CK activity
      posteriorly. This blood collection was repeated 1 minute, 1 hour, 24, 48, 72 and 96 hours
      after eccentric protocol.

      A visual analogue scale (VAS) of 100 mm was used as a self-rating of volunteers DOMS
      intensity, with assistance of a blinded researcher. DOMS assessments were performed at
      baseline, immediately after eccentric exercise protocol (1 minute), and it was repeated at 1,
      24, 48, 72 and 96 hours after the exercise protocol. Before exercise protocol, volunteers
      will perform a stretching and warm-up of the non-dominant lower limb and then they will
      perform Maximum voluntary contraction (MVC) to evaluate muscle function. MVC measurements
      were repeated at the same time intervals as the CK measures.

      The exercise protocol consists in 75 eccentric isokinetic contractions of the knee extensor
      musculature in the non-dominant leg (5 sets of 15 repetitions, 30-second rest interval
      between sets) at a velocity of 60°.seg-1 in both the eccentric and concentric movements with
      a 60° range of motion (between 90° and 30° of knee flexion).

      Regarding to treatment, all volunteers received the treatment according to randomisation
      three minutes after eccentric exercise protocol. Comparators were repeated at 24, 48, and 72
      hours following the collection of additional blood samples for CK analyses and MVC and DOMS
      assessments.

      The five groups was divided in: PBMT (photobiomodulation therapy)+cryotherapy;
      cryotherapy+PBMT; active PBMT; placebo PBMT and only cryotherapy.

      PBMT was applied employing a cordless, portable GameDay™ Super Pulsed Laser (manufactured by
      Multi Radiance Medical, USA) to 6 sites of quadriceps femoris in direct contact with the skin
      (2 centrally - rectus femoral and vastus intermedius; 2 laterally - vastus lateralis; and 2
      medially - vastus medialis) and cryotherapy was done with two flexible ice packs filled with
      ice cubes and water (with a volume of 1.15 liters each) that will cover the entire quadriceps
      for 20 minutes.
    

Intervention name(s): PBMT; Cryotherapy
Intervention type(s): Other; Other
Intervention description(s): Effects of phototherapy isolated and/or combined with cryotherapy in post-exercise skeletal muscle recovery.; Effects of cryotherapy isolated and/or combined with phototherapy in post-exercise skeletal muscle recovery.
Other intervention name(s): photobiomodulation therapy
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: phototherapy; cryotherapy; exercise; fatigue; recovery