Low‐level Laser Therapy Improves Skeletal Muscle Performance, Decreases Skeletal Muscle Damage and Modulates mRNA Expression of COX‐1 and COX‐2 in a Dose‐dependent Manner

Abstract

We tested if modulation in mRNA expression of cyclooxygenase isoforms (COX-1 and COX-2) can be related to protective effects of phototherapy in skeletal muscle. Thirty male Wistar rats were divided into five groups receiving either one of four laser doses (0.1, 0.3, 1.0 and 3.0 J) or a no-treatment control group. Laser irradiation (904 nm, 15 mW average power) was performed immediately before the first contraction for treated groups. Electrical stimulation was used to induce six tetanic tibial anterior muscle contractions. Immediately after sixth contraction, blood samples were collected to evaluate creatine kinase activity and muscles were dissected and frozen in liquid nitrogen to evaluate mRNA expression of COX-1 and COX-2. The 1.0 and 3.0 J groups showed significant enhancement (P < 0.01) in total work performed in six tetanic contractions compared with control group. All laser groups, except the 3.0 J group, presented significantly lower post-exercise CK activity than control group. Additionally, 1.0 J group showed increased COX-1 and decreased COX-2 mRNA expression compared with control group and 0.1, 0.3 and 3.0 J laser groups (P < 0.01). We conclude that pre-exercise infrared laser irradiation with dose of 1.0 J enhances skeletal muscle performance and decreases post-exercise skeletal muscle damage and inflammation.

Time response of increases in ATP and muscle resistance to fatigue after low-level laser (light) therapy (LLLT) in mice

“…Previous studies have used light therapy for muscular preconditioning by delivering the light therapy over the target muscles 5 min before fatigue tests in vivo [27,28] or in clinical trials [20][21][22]. These studies reported an increased number of repetitions and consequently a better fatigue-muscle resistance.…”

Light-emitting diode therapy (LEDT) before matches prevents increase in creatine kinase with a light dose response in volleyball players

“…The effects of low-level laser (light) therapy on muscle tissue when applied before or after intense exercise are mainly related to the prevention of exercise-induced damage, promotion of faster muscle recovery, and also producing increases in performance [10,30,11]. The use of LLLT to prevent muscle damage has been widely investigated in experimental models [15][16][17][18][19][20] and in clinical trials [21][22][23][24][25][26][27][28]. Experimental studies have used animal models to induce muscle damage, and clinical trials have used protocols of exercise in isokinetic dynamometers, fitness machines, or free weight lifting to induce muscle damage.…”

“…More studies using experimental models were conducted to investigate the effects of LLLT on CK activity [18,17,19,20]. Using a similar model of neuromuscular electrical stimulation previously reported [15], other studies also found LLLT dose responses of muscular pre-conditioning by decreased CK activity [18,19], including assessment of different wavelengths [20].…”

“…In order to investigate the effects of LLLT on Bmuscle protection^against exercise-induced muscle damage, different protocols of exercise or neuromuscular electrical stimulation have been used to induce muscle fatigue and damage in experimental models [15][16][17][18][19][20] and in clinical trials [21][22][23][24][25][26][27][28]. These studies have evaluated different wavelengths and different light sources such as diode lasers and light-emitting diodes (LEDs) [29].…”

Ankilozan spondilitte düşük doz lazer tedavisinin ağrı ve fonksiyonellik üzerine etkisi

“…Additionally, the analgesic effect of LLLT is thought to be related to its antiinflammatory action (12)(13)(14)(15). Many experimental and clinical studies have shown that LLLT can reduce or modulate TNF-α levels (13,15).…”