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

Abstract

Low-level laser (light) therapy (LLLT) has been applied over skeletal muscles before intense exercise (muscular pre-conditioning) in order to reduce fatigue and muscle damage (measured by creatine kinase, CK) in clinical trials. However, previous exercise protocols do not exactly simulate the real muscle demand required in sports. For this reason, the aim of this randomized and double-blind placebocontrolled trial was to investigate whether light-emitting diode therapy (LEDT) applied over the quadriceps femoris muscles, hamstrings, and triceps surae of volleyball players before official matches could prevent muscle damage (CK) with a dose response, establishing a therapeutic window. A professional male volleyball team (12 athletes) was enrolled in this study, and LEDT was applied before 4 matches during a national championship. LEDT used an array of 200 lightemitting diodes (LEDs) arranged in 25 clusters of 4 infrared LEDs (850±20 nm; 130 mW) and 25 clusters of 4 red LEDs (630±10 nm; 80 mW). Athletes were randomized to receive one of four different total doses over each muscle group in a double-blind protocol: 105 J (20 s), 210 J (40 s), 315 J (60 s), and placebo (no light for 30 s). CK in blood was assessed 1 h before and 24 h after each match. LEDT at 210 J avoided significant increases in CK (+10 %; P=0.993) as well as 315 J (+31 %, P=0.407). Placebo (0 J) allowed a significant increase in CK (+53 %; P=0.012) as well as LEDT at 105 J (+ 59 %; P=0.001). LEDT prevented significant increases of CK in blood in athletes when applied before official matches with a light dose response of 210-315 J, suggesting athletes might consider applying LEDT before competition.

Photobiomodulation in human muscle tissue: an advantage in sports performance?

“…In this perspective, a muscular pre-conditioning protocol delivered to professional volleyball players, 40–60 minutes before official matches was able to prevent statistically significant muscle damage measured by CK levels in the bloodstream [49], showing that muscular pre-conditioning applied 3–5 minutes before a bout of exercise may not actually be the best time point. Moreover, it is very important to note that several studies (see tables 2, 3 and 4) applied a muscular pre-conditioning PBM protocol using LLLT or LEDT, or both together, and in general showed positive effects in preventing muscle damage and increase muscle performance from 1 h until 72–96 h. These results reinforce previous results in vitro [60,72,65] and in vivo [69–71] regarding the best time window or time-response for PBM to maintain its beneficial effects on biological tissues, may also apply to skeletal muscles in humans.…”

“…to increase fatigue resistance or increase number of repetitions, increase muscle force or work, and decrease CK or related markers of muscle damage [12,30–40,42,43,46–49]. The range in total energy (J) identified to produce the most positive effects was 56–315 J, regardless if PBM was applied as muscular pre-conditioning or after exercise.…”

“…The range in total energy (J) identified to produce the most positive effects was 56–315 J, regardless if PBM was applied as muscular pre-conditioning or after exercise. It is important to note that only energy applied on the quadriceps femoris muscles of the references [33,48,49] were considered in the years 2011, 2015 and 2016, respectively [Figure 7]. The light power and total time of irradiation ranged from 60 mW to 2500 mW and 60 seconds to 3876 seconds, respectively.…”

Mechanisms and applications of the anti-inflammatory effects of photobiomodulation

“…The International Olympic Committee and the World Anti-Doping Agency cannot ban light therapy for athletes considering (1) the intensity is similar to sunlight, and (2) there is no forensic test for light exposure. There have been several clinical trials carried out in Brazil in athletes such as elite runners [94], volleyball players [95] and rugby players [96]. Ferraresi et al conducted a case-controlled study in a pair of identical twins [97].…”

Effects of Light-Emitting Diode Therapy on Muscle Hypertrophy, Gene Expression, Performance, Damage, and Delayed-Onset Muscle Soreness

“…Moreover, increases in ATP content in muscle cells and tissue, fatigue resistance, strength, oxidative stress defense, prevention of muscle damage, and improvement of the kinetics of oxygen consumption 7,8,10,12,17,41–43 can also be elicited when phototherapy is applied to muscles before a single bout of exercise (muscular preconditioning). However, it seems there is an optimum time to apply phototherapy when used in a muscular preconditioning regimen as judged by increases in ATP synthesis in muscles, mitochondrial metabolism, and fatigue resistance that are maximal at some hours after light application.…”