The purpose of this study was to compare the effects of exercise therapy, alternating cold and hot (ACH) therapy and low
intensity laser (LIL) therapy in patients with chronic lumbar muscle strain (CLMS). Thirty-two patients were randomly
allocated to four groups: exercise group, ACH group, LIL group, and combination group of exercise, ACH and LIL, eight
in each group. Sixteen treatments were given over the course of 4 weeks. Lumbar muscle endurance, flexion and lateral
flexion measures, visual analogue scale (VAS) and lumbar disability questionnaire (LDQ) were used in the clinical and
functional evaluations before, immediately after, and 4 weeks after treatment. It was found that the values of endurance,
VAS and LDQ in all groups were significantly improved from before to after treatment (P < 0.01). The combination
group showed significantly larger reduction on pain level and functional disability than the other groups immediately and
4 weeks after treatment (P < 0.01). Pain level reduced significantly more in the ACH group than in the exercise group or
the LIL group immediately and 4 weeks after treatment (P < 0.05). Lumbar muscle endurance and spinal ranges of
motion in all groups were improved after treatment but there was no significant difference between any therapy groups.
In conclusion, exercise therapy, ACH therapy and LIL therapy were effective in the treatment of CLMS. ACH therapy
was more effective than exercise therapy or LIL therapy. The combination therapy of exercise, ACH and LIL had still
better rehabilitative effects on CLMS.
The neural regeneration and functional recovery after nerve injuries has long been an important field in neuroscience.
Low intensity laser (LIL) irradiation is a novel and useful tool for the treatment of many injuries and disorders. The aim
of this study was to assess the role of LIL irradiation in the treatment of peripheral and central nerve injuries. Some
animal experiments and clinical investigations have shown beneficial effects of LIL irradiation on neural tissues, but its
therapeutic value and efficacy are controversial. Reviewing the data of experimental and clinical studies by using the
biological information model of photobiomodulation, we conclude that LIL irradiation in specific parameters can
promote the regeneration of injured peripheral and central nerves and LIL therapy is a safe and valuable treatment for
superficial peripheral nerve injuries and spinal cord injury. The biological effects of LIL treatment depend largely on
laser wavelength, power and dose per site and effective irradiation doses are location-specific.
There are two kinds of pathways mediating cellular photobiomodulation, the specific one is mediated by the resonant interaction of light with molecules such as cytochrome nitrosyl complexes of mitochondrial electron transfer chain, singlet oxygen, hemoglobin or photosensentor such as endogenous porphyrines, the non-specific one is mediated by the non-resonant interaction of light with membrane proteins. Some of specific pathways mediating photobiomodulation can damage membrane or cell compartments such as mitochondria, lysosomes, endoplasmic reticulum by photodynamic damage if the light intensity is very high so that photodynamic damage will limit the maximum intensity of the light of photobiomodulation although the non-specific pathways mediating photobiomodulation might not damage cells. As the reciprocity law, the rule of Bunsen and Roscoe, was not obeyed for almost all the studied photobiomodulation, and the light energy reaps the greatest benefit where it is most needed, photobiomodulation was thought to be dominantly mediated by the non-specific pathways although the specific pathways can act as a role, which is supported by the dose relationship research in which the photobiomodulation effects were found to be the SIN function of radiation time in many works on the dose relationship when the intensity is kept constant. The non-specific pathways were mainly mediated by membrane receptors and the ultraweak non-resonant interaction of light with membrane receptors can be physically amplified by the coherent state of membrane receptors and then chemically exemplified by signal transduction according to our biological information model of photobiomodulation supported by its successful cellular, animal and clinic applications.
Sports injuries healing has long been an important field in sports medicine. The stimulatory effects of Low intensity laser (LIL) irradiation have been investigated in several medical fields, such as cultured cell response, wound healing, hormonal or neural stimulation, pain relief and others. The aim of this study was to evaluate whether LIL irradiation can accelerate sports injuries healing. Some experimental and clinical studies have shown the laser stimulation effects on soft tissues and cartilage, however, controversy still exists regarding the role of LIL when used as a therapeutic device. Summarizing the data of cell studies and animal experiments and clinic trials by using the biological information model of photobiomodulation, we conclude that LIL irradiation is a valuable treatment for superficial and localized sports injuries and that the injuries healing effects of the therapy depend on the dosage of LIL irradiation.
Exercise-induced fatigue has long been an important field in sports medicine. The electron leak of mitochondrial respiratory chain during the ATP synthesis integrated with proton leak and O-.2 can decrease the efficiency of ATP synthesis in mitochondria. And the exercise-induced fatigue occur followed by the decrease of performance. If the dysfunction of mitochondria can be avoided, the fatigue during the exercise may be delayed and the performance may be enhanced. Indeed there are some kind of materials can partially prevent the decrease of ATP synthesis efficiency in mitochondria. But the side effects and safety of these materials is still needed to be studied. Low intensity laser can improve the mitochondria function. It is reasonable to consider that low intensity laser therapy may become the new and more effective way to delay or elimination the fatigue induced by dysfunction of mitochondria. Because the effect of laser irradiation may not be controlled exactly when study in vivo, we use electrical stimulation of C2C12 muscle cells in culture to define the effect of low intensity laser on the dysfunction of mitochondria, and to define the optimal laser intensity to prevent the decrease of ATP synthesis efficiency. Our study use the C2C12 muscle cells in culture to define some of the mechanisms involved in the contractile-induced changes of mitochondrial function firstly in sports medicine and may suggest a useful study way to other researchers. We also give a new way to delay or eliminating the fatigue induced by dysfunction of mitochondria without side effect.