Table 5.
Clinical trials of photobiomodulation (PBM) in chronic responses in exercises with lower limb muscles
| Reference | PBM parameters | Mode of irradiation | Muscle/exercise | Main findings |
|---|---|---|---|---|
| [14] | Cluster with 6 laser diodes 808 nm; Diode area 0.0028cm2; 60 mW; 21.42W/cm2 0.6 J per diode (10 s), 214.28 J/cm2 3.6 J per site of irradiation: 6 × 0.6 J 7 sites of irradiation per limb Total delivered: 25.2 J |
Contact After exercise |
7 sites of irradiation on quadriceps femoris Leg press training and isokinetic dynamometer |
RCT with 36 subjects (12 control; 12 training; 12 training+ PBM) PBM increased load in maximum repetition (1-RM) PBM increased knee extensor peak torque No effect of PBM on thigh perimetry |
| [15] | Cluster with 6 laser diodes 808 nm Diode area 0.0028cm2; 60 mW; 21.42W/cm2 0.6 J per diode (10 s), 214.28 J/cm2 3.6 J per site of irradiation: 6 × 0.6 J 5 sites of irradiation per limb Total delivered: 18 J |
Contact After exercise |
5 sites of irradiation on quadriceps femoris Cycle ergometer training and isokinetic dynamometer |
RCT with 45 subjects (15 control; 15 training; 15 training+PBM) PBM decreased fatigue index of knee extensor muscles No effect of PBM in total knee extensor work |
| [54] | Array with 50 LEDs 850 nm; Diode area 0.2 cm2; 100 mW; 500 mW/cm2; 1.5 J per diode (15 s); 7.5 J/cm2; 75 J applied per muscle group: 50 × 1.5 J Sites of irradiation per limb Quadríceps femoris Total delivered: 150 J |
Contact After exercise |
Irradiation on whole quadriceps femoris Leg press training Leg extension training |
Case-control with 2 subjects monozigotic twins (1 placebo; 1 PBM) PBM increased maximal load PBM increased muscle hypertrophy PBM decreased CK in blood PBM decreased fatigue PBM increased gene expression of muscle hypertrophy and defense against oxidative stress PBM decreased gene expression of inflammation and muscle atrophy |
| [55] | Cluster with 5 laser diodes 810 nm Diode area 0.029 cm2; 200 mW; 6.89 W/cm2 6 J per diode (30 s); 206.89 J/cm2 30 J per site of irradiation: 5 × 6 J 8 sites of irradiation per limb Total delivered: 240 J |
Contact Muscular pre-conditioning |
2 sites of irradiation on vastus medialis 3 sites on vastus lateralis 3 sites on rectus femoris Eccentric training in isokinetic dynamometer |
RCT with 30 subjects (10 control; 10 training; 10 training+PBM) PBM increased muscle thickness PBM increased isometric knee extensor peak torque PBM increased eccentric knee extensor peak torque |
| [56] | Laser diode 660 nm; Diode area 0.06 cm2; 30 mW; 0.5 W/cm2; 0.24 J (8 s), 4 J/cm2; 8 sites of irradiation per limb Total delivered: 1.92 J |
Contact Muscular pre-conditioning and after exercise |
8 sites on triceps surae Vertical jumps |
RCT with 22 subjects (8 control; 7 LLLT-6 days; 7 LLLT-10 days) No effect of PBM on vertical jump performance (power and fatigue) No effect of PBM on delayed onset muscle soreness |
| [57] | Laser diode 808 nm; Diode area 0.028 cm2; 100 mW; 35.71 W/cm2; 7 J (70 s), 250 J/cm2; 8 sites of irradiation per limb Total delivered: 56 J |
Contact After exercise |
8 sites of irradiation on quadriceps femoris Leg extension training |
RCT with 48 subjects (15 control; 17 training+LLLT; 16 training) PBM increased work compared to control PBM increased peak torque compared to control PBM increased power compared to control No effect of PBM on fatigue index No effect of PBM on lactate levels No effect of PBM on 6-min walk test No effect of PBM on surface electromyography No effect of PBM in 1 maximum repetition (1-RM) |
| [59] | Cluster with: 4 laser diodes 905 nm; Diode area 0.44 cm2; 0.3125 mW; 0.71 mW/cm2; 4 LEDs 875 nm; Diode area 0.9 cm2; 17.5 mW; 19.44 mW/cm2; 4 LEDs 640 nm; Diode area 0.9 cm2; 15 mW; 16.66 mW/cm2; 30 J per site of irradiation: 228 s 6 sites of irradiation per limb Total delivered: 180 J |
Contact Muscular pre-conditioning/after exercise/pre-conditioning and after exercise |
2 sites of irradiation on vastus medialis, 2 sites on vastus lateralis 2 sites on rectus femoris Leg press training Leg extension training |
RCT with 48 subjects (12 placebo; 36 PBM) PBM (pre-conditioning only-12 subjects) increased 1-RM in leg press PBM (pre-conditioning only-12 subjects) increased 1-RM in leg extension PBM (pre-conditioning only-12 subjects) increased peak torque in MVC PBM (pre-conditioning and after-12 subjects) added no effect PBM (after only-12 subjects) added no effect PBM (all modalities-36 subjects) did not increase thigh perimetry |