LED therapy or cryotherapy between exercise intervals in Wistar rats: anti-inflammatory and ergogenic effects

Abstract

The aim of this study was to test, between two bouts of exercise, the effects of light-emitting diode (LED) therapy and cryotherapy regarding muscle damage, inflammation, and performance. Male Wistar rats were allocated in four groups: control, passive recovery (PR), cryotherapy (Cryo), and LED therapy. The animals were submitted to 45 min of swimming exercise followed by 25 min of recovery and then a second bout of either 45 min of exercise (muscle damage analysis) or time to exhaustion (performance). During the rest intervals, the rats were kept in passive rest (PR), submitted to cold water immersion (10 min, 10 °C) or LED therapy (940 nm, 4 J/cm(2)) of the gastrocnemius muscle. Blood samples were collected to analyze creatine kinase activity (CK), C-reactive protein (CRP), and leukocyte counts. The soleus muscles were evaluated histologically. Time to exhaustion was recorded during the second bout of exercise. After a second bout of 45 min, the results demonstrated leukocytosis in the PR and Cryo groups. Neutrophil counts were increased in all test groups. CK levels were increased in the Cryo group. CRP was increased in PR animals. The PR group presented a high frequency of necrosis, but the LED group had fewer necrotic areas. Edema formation was prevented, and fewer areas of inflammatory cells were observed in the LED group. The time to exhaustion was greater in both the LED and Cryo groups, without differences in CK levels. CRP was decreased in LED animals. We conclude that LED therapy and cryotherapy can improve performance, although LED therapy is more efficient in preventing muscle damage and local and systemic inflammation.

The Effectiveness of Photobiomodulation Therapy Versus Cryotherapy for Skeletal Muscle Recovery: A Critically Appraised Topic

“…[4][5][6][7][8] There were no studies found in the literature search that supported cryotherapy over PBMT. The PBMT was more effective in preventing increases in CK levels, 4-8 blood lactate, 5 C-reactive protein, 5,7 and inflammation 6,7 after an exercise bout. In addition, PBMT was able to increase time to exhaustion 7 and better maintain muscular strength following strenuous exercise 4,8 compared with cryotherapy.…”

“…This was demonstrated by an increase of CK, blood lactate, and frequency of necrosis, measured by histological analysis, in placebo treatments, 4,5,8 an ice bag application, 4,8 and coldwater immersion therapy. 5,7 Compared with placebo treated groups, cryotherapy demonstrated no difference in CK 4,5,8 or blood lactate 5 levels at any time points. PBMT protected the muscle against damage in the included studies, with significantly lower levels of muscle damage markers [4][5][6][7][8] ; thus, inflammation markers of c-reactive protein [5][6][7] and leukocyte analysis 6,7 were also lower in groups treated with PBMT.…”

“…• Three moderate-to high-quality double-blinded, randomized, placebo-controlled trial studies 4,5 and 2 low-to moderatequality translational rat studies [6][7][8] were included in the critical appraisal.…”

Effects of light-emitting diodes phototherapy on autonomic modulation of footballers

“…Nós aplicamos um comprimento de onda de 940 nm devido ao fato de que maiores comprimentos de onda penetram com maior profundidade no tecido muscular 55 . Prévios estudos mostraram que esse comprimento de onda após exercísio intenso em modelos animais foi capaz de diminuir dano muscular e os processos infl amatórios que ocorrem após exercício intenso 45,56 . As limitações do presente estudo foram o nú-mero pequeno de participantes o qual talvez tenha limitado o poder das análises estatísticas; a falta de medidas diretas da carga externa, como por exemplo, a distância em alta intensidade durante os treinos coletivos e o amistoso (TABELA 2); e a falta de medidas de desempenho ao fi nal da semana de treino.…”

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

“…Another study observed a reduction in CK activity when LLLT was applied after exercises in a model of swimming with workload [17]. Recently, LLLT using LEDs (LEDT) has demonstrated similar benefits to decrease CK activity when applied after exercise [35] or during rest intervals between bouts of physical activity [36]. All these studies assessed CK activity after 24 h or during a time range of 24-48 h after the exercise.…”