Effects of Low Level Laser Therapy On Exercise Induced Muscle Damage in Wrist Flexors Of Untrained Young Adults
Condition: Wrist Injuries
MeSH terms: Wrist Injuries
Study type: Interventional

Summary: 
      The main aim of the current study is to investigate the effects of Low-level Laser Therapy on
      exercise-induced muscle damage of wrist flexors in untrained young adults. A randomized
      controlled trial will be conducted at Sargodha Medical College, University of Sargodha. The
      sample size calculated is 16. The participants will be divided into two equal group; 1)
      Interventional group (Low level laser therapy), 2) Control group (conventional) each having 8
      participants. The study duration will be six months after approval from Research board.
      Blocked randomization sampling technique will be used. The subjects will be randomly assigned
      to any of the interventional or control group. Interventional group will further be allocated
      to prophylactic or therapeutic group. Only Un-trained young Adults, Aged 19-25
      (under-graduate/college and university students) without gender discrimination will be
      included in the study. Tools used in the study will be TALAG Scale (Soreness assessment),
      Goniometer (ROM), Algometer (Pressure¬-pain Threshold), Electronic digital hand Dynamometer
      (Grip Strength) and PRS (Perceived Recovery Status Scale). Data will be collected at
      baseline, 1hr, 24hr, 72hr, 96hr, 120hr, 148hr, 168hr and 192 hrs after the induction
      protocol.
    

Detailed description: 
      Wrist flexors play a crucial role in hand function. This group of small muscles is of high
      importance in our day to day tasks like carrying heavy objects and for activities in which
      forceful and/or rapid wrist flexions are required. Apart from this, the wrist flexors have a
      distinctive neural control as compared to the other surrounding musculature.

      Muscle exhaustion that is induced after eccentric exercise, can either be of acute onset or
      delayed onset. Exercise induced muscle soreness that persists for about 4 to 6 hours before
      it returns to pre-exercise level is termed as acute soreness. On the other hand, muscle
      soreness beginning at 8 to 24 hours after eccentric exercise, with peak level at 24 to 48
      hours is known as delayed soreness. Delayed-Onset Muscle Soreness (DOMS) is a common
      neuromuscular condition characterized by increased sensitivity to pain that is apparent with
      unaccustomed or vigorous exercise, a day after performance. DOMS becomes evident about 6-8
      hours after an intense exercise bout and peaks at approximately 24-72 hours post-exercise.
      During first few hours of intensive exercise metabolism get disturbed that leads to
      inefficient physical activity and performance. Prolonged metabolic disturbances and physical
      activity and performance impairment progressing to days ultimately induce tissue damage that
      we call as delayed-onset muscle soreness. Event that produces muscle soreness is suggested as
      a mechanical disruption of sarcomeres leading to swelling of injured muscle fibers thus
      initiating an inflammatory response leading to the excitement of nociceptors.

      Exercise-induced muscle injury is similar in pathological change and pathogenic mechanism in
      humans and animals. Human beings and animals have shown parallel reactions to changes caused
      by muscle damage induced by eccentric exercises. The beginning of initial exercise-induced
      muscle damage may be draining but is pain free. Later on, after 8-24 hours of muscle damage
      initiation, the subsequent inflammation results in delayed onset of muscle soreness.

      It has been assumed that whenever an un-habitual physical exercise is carried out by a person
      then muscle injury occurs. A high level of muscle injury is associated with eccentric
      activities. Muscle injury is more likely to occur in untrained individuals who start
      practicing exercise. Furthermore, incidence of muscle injury is more common with exercises
      involving eccentric activities. Loss of strength, muscle inflammation, high level of muscle
      proteins in blood and delayed onset of muscle soreness DOMS are considered to be the expected
      outcomes of muscle injury. Different electro-physical modalities are being used by Physical
      therapists. In many conditions, improved healing and functioning are achieved by the use of
      these electro-physical modalities. Some animal studies have also reported the positive role
      of Low-Level Laser Therapy, when used in optimal parameters of irradiations, in enhancing the
      muscle healing and decreasing inflammation. Increased amount and activity of mitochondria and
      increased cross-sectional area of muscle fiber is associated with training. Increased muscle
      mass and improved mitochondrial function result in shift in muscle fiber type composition,
      from type two B to type Two A, and an increase in local glycogen storage capability. These
      combined adaptations make specialized athletes chiefly different from untrained people.

      Several studies performed on human and animals evidenced the action of Low-level Laser
      Therapy in achieving therapeutic and physiological effects involving improvement of muscle
      functioning through interaction with biological tissues. Decrease in muscle fatigue has been
      reported by several researchers with the application of Laser Therapy before exercises that
      induces fatigue while considerable functional enhancement has also been evidenced by some
      investigators with Laser application after performing fatigue inducing exercises. Therapeutic
      effect of LLLT may be explained by mechanisms involving improved microcirculation of tissue,
      anti-inflammatory effect, decreased oxidative stress and decrease in tissue ischemia.

      In 2016, a study was conducted to evaluate the effects of low level laser therapy on post
      exercise recovery of skeletal muscle and improvement in muscle performance and function. The
      conclusion of this study was that pre-exercise treatment with low level laser therapy
      increases muscle performance along with improvement in biochemical markers associated with
      inflammation and muscle injury.

      In August 2011, Wouber Hérickson de Brito and fellows carried out a comparative study to
      investigate whether muscle performance could be increased with endurance training associated
      with LLLT when compared to the same training without LLLT. Results suggested a great decrease
      in fatigue when training was combined with LLLT, thus improving the muscle performance.

      In August 2010, a study was carried out to find out the effectiveness of low-level laser
      therapy (LLLT) on muscle performance, fatigue development, and biochemical markers of
      post-exercise recovery on bicep muscle. Results clearly suggested that endurance for
      repetitive elbow flexion has been increased with the application of LLLT before exercise
      while levels of reactive protein, creatine kinase and blood lactate has been decreased after
      performance of exercise.

      In July 2010, to investigate the effects of Low-level laser therapy before eccentric exercise
      on muscle damage markers in humans. It was concluded that LLLT therapy when given before
      performance of eccentric exercise, accelerated the increase of muscle proteins in the blood
      serum and the decrease in muscle force.

      In July 2011, a study was carried out to compare the effects of Red (660 nm) and infrared
      (830 nm) low-level laser therapy in skeletal muscle fatigue in humans. The study showed that
      both red and infrared LLLT are effective in delaying the development skeletal muscle fatigue
      and in improvement of skeletal functioning.

      In August 2009, to investigate the Effects of Low-Level Laser Irradiation on Skeletal Muscle
      Injury after Eccentric Exercise. It was the first study performed on animal model to
      investigate these effects. It was concluded that Low-level He-Ne laser therapy exerts
      therapeutic effects by improving anti-oxidative capacity of muscle as well as decreasing the
      inﬂammatory reaction.
    

Intervention name(s): low level laser therapy; Conservative treatment
Intervention type(s): Other; Other
Intervention description(s): Endo-laser 422 with interchangeable laser probes will be used for the purpose. It is a 2-channel unit and is software operated. For treatment of small surfaces with mono laser there are diodes of 25, 100 and 500 milliWatt.Frequency will be adjusted to 500 Hz, dose 0.1/cm2 with time duration of 1-5 minutes.; (Topical ibuprofen gel) for muscle soreness will be provided
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: exercise induced muscle damage; wrist flexor; low level laser therapy