Phototherapy during treadmill training improves quadriceps performance in postmenopausal women

Abstract

Objective To evaluate the effects of infrared-light-emitting diode (LED) during treadmill training on functional performance.Methods Thirty postmenopausal women aged 50 -60 years were randomly assigned to one of three groups and successfully completed the full study. The three groups were: (1) the LED group, which performed treadmill training associated with phototherapy ( n ϭ 10); (2) the exercise group, which carried out treadmill training only ( n ϭ 10); and (3) the sedentary group, which neither performed physical training nor underwent phototherapy ( n ϭ 10). Training was performed over a period of 6 months, twice a week for 45 min per session at 85 -90% of maximal heart rate, which was obtained during progressive exercise testing. The irradiation parameters were 100 mW, 39 mW/cm 2 and 108 J/cm 2 for 45 min. Quadriceps performance was measured during isokinetic exercise testing at 60 ° /s and 300 ° /s.Results Peak torque did not differ amongst the groups. However, the results showed signifi cantly higher values of power and total work for the LED group ( Δ ϭ 21 ϩ Ϫ 6 W and Δ ϭ 634 ϩ Ϫ 156 J, p Ͻ 0.05) when compared to both the exercise group ( Δ ϭ 13 ϩ Ϫ 10 W and Δ ϭ 410 ϩ Ϫ 270 J) and the sedentary group ( Δ ϭ 10 ϩ Ϫ 9 W and Δ ϭ 357 ϩ Ϫ 327 J). Fatigue was also signifi cantly lower in the LED group ( Δ ϭ Ϫ 7 ϩ Ϫ 4%, p Ͻ 0.05) compared to both the exercise group ( Δ ϭ 3 ϩ Ϫ 8%) and the sedentary group (Δ ϭ Ϫ 2 ϩ Ϫ 6%).Conclusions Infrared-LED during treadmill training may improve quadriceps power and reduce peripheral fatigue in postmenopausal women.

Photobiomodulation and physical exercise on strength, balance and functionality of elderly women

“…This interaction could prevent muscle fatigue and enhance muscle strength as demonstrated in a previous study [24,25]. Moreover, it would provide benefits to improve the functional and balance capacity, within a population.…”

Effects of Low-Level Laser Therapy Applied Before Treadmill Training on Recovery of Injured Skeletal Muscle in Wistar Rats

“…30 Other studies also showed the potential benefits of phototherapy applied after exercise programs in animals, including the biomodulation of cytokines, stimulation of insulin-like growth factor 1 (IGF-1) production, increasing muscle volume, 38 as well as increasing MMP-2 gene expression and decreasing lactate levels, indicating a skeletal muscle remodeling and an enhanced functionality. 39 In addition, the phototherapy applied during high intensity exercise was able to promote an improvement in both power muscle and fatigue resistance without leading to muscle damage. 39 Therefore, phototherapy has a protective effect against muscle damage.…”

“…39 In addition, the phototherapy applied during high intensity exercise was able to promote an improvement in both power muscle and fatigue resistance without leading to muscle damage. 39 Therefore, phototherapy has a protective effect against muscle damage. Ribeiro et al 40 demonstrated that LLLT previously applied to muscle injury reduces myonecrosis and inflammatory cells, increases blood vessels and immature muscle fibers as well as increasing MMP-2 activity, decreases collagen deposition, and provides a better collagen organization and distribution.…”

“…Several clinical trials have been investigating the effects of phototherapy before, 43 during, 27,39 and after physical exercise, 42 demonstrating improvements in muscle function as well as a protective effect on muscle. Therefore, phototherapy and physical exercise may lead to the development of new treatment strategies for skeletal muscle injuries, and future studies should be performed.…”

Low‐level laser therapy associated with high intensity resistance training on cardiac autonomic control of heart rate and skeletal muscle remodeling in wistar rats

“…Resistance exercise has been shown to improve lipid profile , glucose tolerance and insulin sensitivity, increase basal metabolic rate, heart rate variability (HRV) and muscle and bone mass , and reduces body fat, blood pressure, and fatigue. In addition, phototherapy has been combined with dynamic exercise to enhance physical performance and improve health in experimental models and clinical trials .…”