Low reactive-level laser therapy (LLLT) has been reported to reduce chronic and acute pain. Recently, some studies have shown that LLLT may also delay skeletal muscle fatigue during high-intensity exercise. We have hypothesized that laser irradiation may also attenuate muscle fatigue or pain experienced after sports or exercise. However, only a few reports have described the use of lasers in sports medicine. This study was conducted to determine the effectiveness of LLLT in aiding the recovery from exercise-induced skeletal muscle fatigue. Subjects and Methods: Isometric plantar flexion was repeatedly performed on 9 students until the force output declined to 50% maximal voluntary contraction (MVC). Subjects were assigned to perform 3 experiments under different LLLT conditions: laser irradiation to the neck (NKL), to the muscle (MSL), and no laser irradiation (CON). MVC and muscle hardness, girth, blood oxygen saturation, and heart rate were measured during the pre-exercise, post-exercise, and recovery phases. The neck and muscle were irradiated for 15 s using the Oh-Lase HT 2001 semi-conductor laser (830 nm; 60 mW, continuous wave), immediately after MVC measurement during the post-exercise phase.
Results: The total exercise time and mean output forces were analyzed using repeated-measures and one-factor ANOVA with post-hoc tests; no significant differences were observed among the 3 conditions for the pre and post-exercise MVC levels before irradiation (NKL, 68.1% MVC; MSL, 66.4% MVC; CON, 66.1% MVC). However, the MVC at 5 and 10 min after exercise was significantly greater in the NKL and MSL groups than in the CON group (MVC after 5 min: 80.4%, 76.9%, and 69.7% for the NKL, MSL, and CON groups, respectively; MVC after 10 min: 81.8%, 81.2%, and 74.4%). Further, no significant differences were observed in the MVC recorded at 15 and 30 min. Therefore, compared to the CON group, the NKL and MSL groups exhibited early muscle-strength recovery from fatigue caused by repeated contractions.
Conclusion: We concluded that LLLT at the parameters used in the present study effectively promoted the recovery of the isometric force output after muscle fatigue induced by repeated contractions, especially in the acute-exhaustion phase.

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The objectives of this study were to evaluate the impact of two different sizes of zona pellucida thinning area by laser assisted hatching on the clinical outcome of cryopreserved cleaved embryos (Experiment 1) and two different sizes of zona pellucida opening area by laser assisted hatching on the clinical outcome of cryopreserved cleaved embryos that were cultured to blastocyst (Experiment 2). A total of 120 cryopreserved cleaved embryo transfers were assigned to either quarter or half of zona pellucida thinning group. Laser assisted hatching was conducted at the cleavage-stage. The rates of clinical pregnancy (47 versus 25%) and implantation (32 versus 16%) were significantly greater in the half thinning group than in the quarter thinning group (P = 0.0218 and P = 0.0090, respectively) (Experiment 1). A total of 71 cryopreserved cleaved embryo transfers were assigned to either one eighth or half of zona pellucida opening group. The cryopreserved cleaved embryos were cultured to blastocyst and laser assisted hatching was conducted at the blastocyst-stage. The rates of clinical pregnancy (74 versus 43%) and implantation (52 versus 27%) were significantly greater in the half opening group than in the one eighth opening group (P = 0.0090 and P = 0.0117, respectively) (Experiment 2). Our results suggest that the size of zona pellucida thinning area or opening area can affect the clinical outcome of cryopreserved cleaved embryo transfers.

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Verruca vulgaris is a benign proliferative lesion of the skin caused by the human papillomavirus (HPV). It is commonly seen in dermatologic and/or plastic surgery clinics. The diagnosis is straightforward, but the treatment of the lesion may be difficult and lengthy. Several treatment methods have been reported but no specific therapy of choice has been developed. It has been suggested that pulsed dye laser treatment is highly effective in the treatment of viral warts which have not responded to other treatments. Pulsed dye laser treatment is a safe method with low side effects and is mostly well-tolerated by patients. Several authors have recently reported the efficiency of pulsed dye laser treatment for warts, but no report has paid attention to the influence of low levels of laser irradiation about the periphery of the treated lesion which may induce immune activation and pain alleviation. We believe these effects are mainly due to the athermal and atraumatic simultaneous Low reactive Level Laser Therapy effect on photobiomodulated cells at the periphery of the treated lesion. We call this coincident duality of thermal damage and athermal stimulation ‘auto-simultaneous laser treatment’. We report herein on pulse dye laser treatment for a recalcitrant huge viral wart and consider the vital response.

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