Table 2.

PBM in human studies without effects.

No	References/Year	Type of Study	Type of Light/Devices	PBM Before/After Activity	Total Energy (J) Applied	Types of Physical Activities	Stimulated Muscles	Analyzed Parameters	Conclusions
[38]	Dutra, Y.M.; Claus, G.M.; Malta, E.S.; et al. Photobiomodulation 30 min or 6 h prior to cycling does not alter resting blood flow velocity, exercise-induced physiological responses or time to exhaustion in healthy men. Front. Physiol. 2021, 15, 11, 607302. doi:10.3389/fphys.2020.607302.	RCT	Multi diode array	Before	152 J	Cycling	Quadriceps, hamstrings, gastrocnemius muscles	Plasma nitrogen CK and lactate	PBMT did not improve exercise-induced changes in cardiorespiratory responses or metabolic blood markers or time to exhaustion during the severe intensity cycle performed by untrained men.
[39]	Malta, E.S.; de Lira, F.S.; Machado, F.A.; et al. Photobiomodulation by led does not alter muscle recovery in-dicators and presents similar outcomes to cold-water immersion and active recovery. Front. Physiol. 2019, 14, 9, 1948. doi:10.3389/fphys.2018.01948.	Double-blind, randomized, and placebo-controlled design	Cluster multi-diode containing 104 LED 56 diodes 660 nm and 48 diodes 850 nm.	Before	600 J (300 J per foot in 5 spots)	High-intensity interval training Cold water immersion	Two regions of the quadriceps muscle, two regions of the biceps femoris, and one region between the soleus and gastrocnemius muscles.	IL-10, TNFα, CK; LDH, DOMS, CMJ, SIT	PBMT had no effect on inflammation, muscle injury, CMJ, DOMS or performance after two consecutive sprint interval training sessions compared to placebo, CWI and AR strategies.
[40]	Orssatto, L.B.R.; Detanico, D.; Kons, R.L.; et al. Photobiomodulation therapy does not attenuate fatigue and muscle damage in judo athletes: A randomized, triple-blind, placebo-controlled trial. Front. Physiol. 2019, 10, 811. doi:10.3389/fphys.2019.00811.	Randomized, Triple-Blind, Placebo-Controlled Trial.	LASERs (850 nm) LEDs (670 nm) LEDs (880 nm) LEDs (950 nm) Number of Diodes = 33 (5, 12, 8, 8)	Before	Dose per site = 30 J. Total dose = 450 J Quadriceps = 240 J, Hamstrings = 120 J, Gastrocnemius = 60 J.	Sixteen judo athletes	Fifteen sites on each lower limb: eight sites on the quadriceps (three sites on vastus lateralis, three sites on rectus femoris, and two sites on vastus medialis), four sites on the hamstrings (two on semitendinosus and two on semimembranosus), two sites on the gastrocnemius (one on lateralis and one on mediallis areas), and one site on the soleus.	CMJ (impulse, peak power, peak velocity, and peak force). Rate of perceived exertion, fatigue, and muscle soreness.	No effect of PBM used before exercise to reduce lower limb muscle fatigue and damage during and following a stretch-shortening cycle protocol in judo athletes.
[41]	Orssatto, L.B.R.; Rossato, M.; Vargas, M.; Diefenthaeler, F.; de la Rocha Freitas, C. Photobiomodulation therapy effects on resistance training volume and discomfort in well-trained adults: A randomized, double-blind, placebo-controlled trial. Photobiomodul. Photomed. Laser Surg. 2020, 38, 12, 720–726. doi:10.1089/photob.2019.4777.	Randomized crossover design, placebo-controlled and double-blind. 14 well-trained adults. Visited laboratory three times, 7 days apart.	Cluster: 5 Lasers and 28 LEDs. Pulse mode (CW) 5 Lasers (850 nm), Irradiance at target: 1666.6 mW/cm2; 12 LEDs (670 nm), 5.20 mW/cm2; 8 LEDs (880 nm), 19.53 mW/cm2; 8 LEDs (950 nm), 11.71 mW/cm2; Exposure duration: 64 s; Radiant exposure: 0.9933 J/cm2.	Before	60 J per site, 6 sites per limb, on each calf. Total dose = 360 J per calf. Area irradiated: 30.2 cm2. Second and third visits, subjects were randomly submitted to PBMT.	In the first visit, 12-repetition maximum (12-RM) test was performed unilaterally on the standing calf raise machine. Resistance training session, performed unilaterally with six sets of repetitions to concentric failure.	The gastrocnemius and soleus muscle.	Rate of perceived exertion for discomfort (RPE-D). Force reduction. Repetitions fatigue index. Total repetitions volume.	PBMT has not been helpful in increasing volume or reducing discomfort during resistance training and conducted to concentric failure to well-trained participants.
[42]	Dutra, Y.M.; Claus, G.M.; Malta, E.S.; et al. Acute photobiomodulation by LED does not alter muscle fatigue and cycling performance. Med. Sci. Sports Exerc. 2020, 52, 11, 2448–2458. doi:10.1249/MSS.0000000000002394. Erratum in: Med. Sci. Sports Exerc. 2021, 53, 5, 1099. https://doi.org/10.1249/MSS.0000000000002644.	Pseudorandomized and balanced, crossover design.	18 × 38 cm matrix with 200 diodes	Before	260 J and 130 J	Cycling	-	Blood lactate concentrations, respiratory responses, EMG activity and capillary gasometry.	PBMT at doses of 260 J and 130 J had no beneficial effects on muscle fatigue, cyclic performance, metabolic parameters and muscle activity in men during recreational cycling.
[43]	Dos Santos, I.A.; Lemos, M.P.; Coelho, W.V.H.M.; et al. Acute photobiomodulation does not influence specific high-intensity and intermittent performance in female futsal players. Int. J. Environ. Res. Public Health 2020, 17, 19, 7253. doi:10.3390/ijerph17197253.	Randomized cross-over, placebo-controlled and double-blind design,	Diodes: 69: 34 diodes 660 nm and 35 diodes 850 nm CW	Before	Energy density = 4.5 J/cm2 (energy dose: 200 J).	Amateur female futsal players	Fifteen minutes of PBMT (1 min 30 s each muscular point; five muscular points in each lower limbs).	CMJ, blood lactate concentration, SmO2, HR, RPE for the YYIR1 test.	PBMT used before high-intensity and intermittent exercise did not influence performance, physiological and perceptual responses in amateur female futsal players.
[50]	Medeiros, D.M.; Aimi, M.; Vaz, M.A.; et al. Effects of low-level laser therapy on hamstring strain injury re-habilitation: A randomized controlled trial. Phys. Ther. Sport 2020, 42, 124–130. doi:10.1016/j.ptsp.2020.01.006.	Randomized controlled trial	Cluster probe consisting of five infrared diodes (850 nm, CW, 100 mW, density energy per diode = 206.9 J/cm2	After	90 J/leg	Male athletes	Three sites; biceps femoris, medial hamstring 60 s.; 90 J/leg	PSLR, KET, SLR, MHFAKE Injury grade I and II; injury site (proximal, distal) strength deficit, Pain.	PBM did not improve functional rehabilitation after HSI in amateur athletes after an exercise program.
[56]	Ghigiarelli, J.J.; Fulop, A.M.; Burke, A.A.; et al. Effects of whole-body photobiomodulation light-bed therapy on creatine kinase and salivary interleukin-6 in a sample of trained males: A randomized, crossover study. Front. Sports Act Living 2020, 29, 2, 48. doi:10.3389/fspor.2020.00048.	Randomized, counterbalanced, cross-over design	Mixed, 660 and 850 nm, with 2800 diodes	Before and after	Total energy emitted over 15 min period = 473 J and 400 J.	Trained males underwent an exercise-induced muscle-damaging training session.	Bench Press; chin-ups Repeated sprints Cycling	CK; salivary IL6	PBMT did not significantly reduce the activity of salivary IL-6 or CK concentration during post-intensity recovery endurance training for 24 to 72 h.
[66]	Malta, E.D.S.; De Poli, R.A.; Brisola, G.M.; et al. Acute LED irradiation does not change the anaerobic capacity and time to exhaustion during a high-intensity running effort: A double-blind, crossover, and place-bo-controlled study: Effects of LED irradiation on anaerobic capacity and performance in running. Lasers Med. Sci. 2016, 31, 7, 1473–1480. doi:10.1007/s10103-016-2011-y.		104 diodes (56 diodes of 660 nm and 48 diodes of 850 nm) Frequency 0–1500 Hz Optical output 10 mW (660 nm) and 30 mW (850 nm)	After a high-intensity running effort	600 J (300 J per leg) 1.5 J/cm2 from each red LED and 4.5 J/cm2 from each infrared LED 30 s at each point	Fifteen moderately active and healthy males underwent a graded exercise test and two supramaximal exhaustive efforts at 115% of the intensity associated with maximal oxygen uptake performed after acute LEDT or placebo	Two regions of the quadriceps muscle, two regions of the biceps femoris, and one region between the soleus and gastrocnemius muscles following the distribution axis of the muscle fibers in both legs.	RPE, MAODALT VO2MAX iVO2MAX REREX; HREX La − P RPEEX	PBMT after a high-intensity running effort did not alter the MAODALT, metabolic energy pathways, or high-intensity running performance.
[67]	Peserico, C.S.; Zagatto, A.M.; Machado, F.A. Effects of endurance running training associated with photo-biomodulation on 5-km performance and muscle soreness: A randomized placebo-controlled trial. Front. Physiol. 2019, 10, 211. doi:10.3389/fphys.2019.00211.	Randomized, placebo-controlled study	LEDs: 56 red diodes (660 nm) and 48 IR (850 nm).	Before all endurance training sessions.	Five points per leg, 60 J at each point, and a total energy of 300 J/per leg.	Thirty untrained subjects in 5-km performance test.	PBMT on 2 sites of the quadriceps muscle, also 2 on the biceps femoris, and one on the gastrocnemius muscle, for 30 s each point.	V-peak test, t-lim test, and 5-km running performance for both groups at pre- and post-training.	Inferential analysis did not show clear significant differences in Vpeak and t5-km for PBM group compared to placebo, and only a moderate effect in relieving muscle pain in the third week of training.
[68]	Zagatto, A.M.; Dutra, Y.M.; Lira, F.S.; et al. Full Body Photobiomodulation Therapy to Induce Faster Muscle Recovery in Water Polo Athletes: Preliminary Results. Photobiomodul. Photomed. Laser Surg., 2020, 38, 766–772. https://doi.org/10.1089/photob.2020.4803.	Randomized, parallel, and double-blinded design.	Full body PBMT 6 panels of 76 red (660 nm, 80 mW each at 30 cm of distance) and 74 IR (850 nm, 65 mW each at 30 cm of distance) LEDs, totaling 900 LEDs distributed over an area of 12,193 cm2 = 1.2193 m2	Immediately after official water polo matches	Total average radiant power (mW) = (80 + 65) = 145. Total average power density (mW/cm2) (25.47 + 20.70) = 46.17 Total average energy density (J/cm2) (3.8 + 3.1) = 6.9	Thirteen water polo athletes (whole team).	Full body PBMT, 30 cm far from the device; irradiation time in continuous mode = 5 min (2 min 30 s to front plus 2 min 30 s back).	Before each match (2–3 h): heart rate variability (HRV) in rest; blood samples for testosterone and cortisol; CK, LDH; TNF-a, IL-6; MVC and squat jump.	Full body PBMT did not induce faster recovery of inflammatory, muscle damage (excepting LDH), testosterone, cortisol, HRV, and neuromuscular responses during repeated days of water polo matches.
[69]	Segabinazi Peserico, C.; Garozi, L.; Zagatto, A.M.; et al. Does Previous Application of Photobiomodulation Using Light-Emitting Diodes at Different Energy Doses Modify the Peak Running Velocity and Physiological Parameters? A Randomized, Crossover, Double-Blind, and Placebo-Controlled Study. Photobiomodul. Photomed. Laser Surg. 2020, 38, 12, 727–733. doi:10.1089/photob.2019.4791.	Randomized, crossover, double-blind, placebo-controlled. 15 physically active males divided into 4 groups: placebo (PLA) and 3 PBM groups with different application doses: PBM1: 30 J per area PBM2: 120 J per area PBM3: 180 J per area	Fifty-six red diodes (660 nm); 50 mW/cm2 1.5 J/cm2 each diode; and 48 IR diodes (850 nm); 150 mW/cm2 4.5 J/cm2 each diode.	Five minutes before treadmill tests.	Cumulative dose (on body) 300 J, 1200 J, or 1800 J; Application time (per point): 15, 60, or 90 s. Number of irradiation points (per leg) 5 points. Number of irradiation points (on body) 10 points. Total application time 75, 300, or 450 s.	Treadmill tests for the determination of Vpeak.	Two regions of the quadriceps muscle, two regions of the femoral biceps muscle, and one region of the gastrocnemius muscle in both legs.	HRmax, maximal heart rate; LApeak, peak blood lactate concentration; RPEmax, maximal rating of perceived exertion; Vpeak, peak running velocity.	Application of different doses of PBM using LEDs did not modify Vpeak and physiological and perceptual parameters.
[70]	Dellagrana, R.A.; Rossato, M.; Orssatto, L.B.R. et al. Effect of Photobiomodulation Therapy in the 1500 m Run: An Analysis of Performance and Individual Responsiveness. Photobiomodul. Photomed. Laser Surg. 2020, 38, 734–742. doi:10.1089/photob.2019.4785.	Randomized, crossover, double-blind placebo-controlled trial. 19 recreationally trained runners.	Mixed wavelength device Cluster: 5 LASERs of 850 nm, 12 LEDs of 670 nm, 8 LEDs of 880 nm, 8 LEDs of 950 nm. Continuous mode (CW).	Before time trial run.	30 J per site, with a total energy dose of 840 J. Exposure duration: 32 s.	1500 m run	Total points irradiated = 28. 14 sites per each lower limb: 8 sites on the quadriceps, 4 sites on the hamstrings, and 2 sites on the gastrocnemius.	Maximum oxygen uptake (VO2MAX); Velocity associated with VO2MAX (vVO2MAX); PV; Maximal heart rate (HRMAX); Respiratory compensa tion point (RCP).	PBMT applied immediately before running in non-controlled environment was not able to improve the 1500 m performance of recreationally trained runners.
[71]	Abreu, J.S.S.; Dos Santos, G.V.; Fonsati, L.; et al. Time-Response of Photobiomodulation Therapy by Light-Emitting Diodes on Muscle Torque and Fatigue Resistance in Young Men: Randomized, Double-Blind, Crossover and Placebo-Controlled Study. Photobiomodul. Photomed. Laser Surg. 2020, 38, 12, 750–757. doi:10.1089/photob.2020.4813.	Randomized, double-blind, placebo-controlled, crossover trial. 30 healthy and physically active young men, divided into two groups: PBMT (15) and placebo (15).	Flexible array of 132 LEDs: 60 red (635 nm), 72 IR (880 nm). Frequency: 4.7 KHz. Optical power (each LED): 1.2 mW (red) 15 mW (IR). Total optical power: 1152 mW. Area (each LED): 0.2 cm2. Effective area of irradiation: 166.75 cm2. Power density (each LED): Red: 6 mW/cm2; IR 75 mW/cm2; irradiation time: 52 s.	5 min, 1 h, 3 h, and 6 h preconditioning PBMT.	Total energy (of the device) 60 J; 1152 mW; 52 s; 166.75 cm2, applied on biceps brachii.	Maximal voluntary isometric contractions (MVIC) of elbow flexion.	Biceps brachii (small muscle) = elbow flexor muscles.	Peak torque (PT), rate of torque development (RTD), fatigue resistance, subjective perception of effort in maximal voluntary isometric contractions (MVIC) of elbow flexion.	PBMT was not effective to increase muscle performance and decrease fatigue to demonstrate the possible time–response in humans.