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Objective: To identify the prevalence of injuries in male adults' athletes of the Brazilian team of taekwondo. Methods: Eleven athletes aged of 24±4.5 years answered two semi-structured questionnaires and objective questions for investigation of the following aspects: age; time practicing; taekwondo's graduation; anatomical region injured during training and/or competitions; injury mechanisms during competitions and training; periodization; duration and frequency of training and competitions in the last year; and if there was interruption of taekwondo practice due to injuries. Results: The contusion was the most frequent injury, and the lower limbs were most affected, 27% reported discontinuation of training and/or competition greater than or equal to 1 day due to injuries. The mean frequency of competitions; training days per week and training months per year were: 6±3 times/year; 5±1 days/week and 10±3 months/year. Conclusion: The most prevalent injury of athletes from the Brazilian team of taekwondo was the contusion in the thigh and forearm during competitions. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to determine the effects of a progressive loading exercise program on the bone and skeletal muscle properties of female osteopenic rats. Forty female Wistar rats (12 weeks old) were divided into four groups (n =10): sham-operated sedentary (SS); osteopenic-sedentary (OS); sham-operated training (ST) and osteopenic training (OT). Osteopenia was induced by ovariectomy (OVX). The exercise program was performed every 48h for 8 weeks and consisted of four bouts of 10 jumps. After 8 weeks, the animals were sacrificed and submitted to bone and muscle excision. The tibias were submitted to an evaluation of the physical properties and a biomechanical test. The soleus and tibialis anterior muscles were weighed and frozen for a cross-sectional area evaluation. Osteopenic sedentary animals showed a decrease in bone strength, weight and density. The OT group showed higher values for ash weights, bone mineral density and strength, as compared to the OS group. The soleus and tibialis anterior muscles of the OT group weighed more than those of the osteopenic sedentary and ST groups. Moreover the muscle weight showed a significant positive correlation to bone strength. The results of this study suggest that the exercise program had a stimulatory effect on the bone and muscle tissue of osteopenic rats, leading to the suggestion that muscle tissue hypertrophy could have a stimulatory effect on bone mass. [Copyright &y& Elsevier]

The aim of this study was to evaluate the effects of stretching and therapeutic ultrasound (TUS) on desmin and laminin contents of rat muscle after contusion. Male Wistar rats (n = 35, 8–9 weeks of age, 271 ± 14g body weight) were divided into five groups: Control group (CG) (n= 03); Injured group (IG) (n= 8); Injured + ultrasound group (IUSG) (n= 8); Injured+stretching group (ISG) (n= 8); Injured +ultrasound + stretching group (IUSSG) (n= 8). The application of ultrasound started 72 hours after the contusion, using the 50 % pulsed mode, 0.5 W/cm2, 5 min, once a day, for five consecutive days. Passive manual stretching was started on the tenth day after injury, with four repetitions of 30 s each and 30 s rest between repetitions, once a day, five times per week, for a total of ten applications. After 22 days, the rats were euthanazied and the gastrocnemius of both limbs removed for desmin and laminin immunohistochemistry morphometric measurement. Analysis was conducted using ANOVA one way post-hoc Tukey to parametric data and Kruskall-Wallis for non-parametric data. The IUSSG animals showed a larger area of desmin than ISG (p<0.05). It was found a decrease in laminin comparing IUSG to IG. However, laminin area was higher in ISG than all groups (p<0.05). UST isolated or in combination with stretching influenced gastrocnemius regeneration in different manners. While stretching applied isolated enhanced gastrocnemius regeneration noticed by the increase in laminin area, in combination with TUS strengthened the muscle healing rising desmin area. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the chronic effects of stretching exercise on soleus muscle histomorphology and histomorphometry of young and aged rats. Thirty-eight female rats were divided into young control group (YCG, n=10;274±50 g); young stretching group (YSG, n=8;274±12 g); aged control group (ACG, n=10;335±39 g); and aged stretching group (ASG, n=10;321±32g). A mechanical apparatus was used to stretch muscle in 4 repetitions, 60 s each, 30 s interval between repetitions in each session, 3 times a week for 3 weeks. Twenty-four hours after the last stretching session, soleus muscle was removed for micromorphology and immunostaining analysis. Data analyses were performed with one-way ANOVA, post-hoc Tukey, or Kruskal-Wallis tests for parametric and nonparametric, respectively (p£0.05). Muscle fiber cross-sectional area (MFCSA) of ACG was lower (18 %) compared to the YCG. Stretching increased MFCSA comparing YSG to YCG (5,681.15± 1,943.61 mm2 vs 5,119.84±1,857.73 mm2, p=0.00), but decreased comparing ASG to ACG (3,919.54± 1,694.65 mm2 vs 4,172.82±1,446.08 mm2, p=0.00). More serial sarcomere numbers were found in the YSG than YCG (12,062.91±1,564.68 vs 10,070.39±1,072.38, p=0.03). Collagen I and collagen III were higher in YSG than ASG (7.44±7.18 % vs 0.07±0.09 %, p=0.04) and (14.37 %± 9.54 % vs 5.51 %±5.52 %, p=0.00), respectively. TNF-a was greater in ASG than YSG (43.42 %±40.19 % vs 1.72 ± 2.02 %, p=0.00). Epimysium was larger in the YSG compared to YCG (201.83±132.07 % vs 181.09±147.04 %, p=0.00). After 3-week stretching the soleus muscles from aged rats were smaller than their younger counter-parts. Interestingly, while stretching appeared to positively affect young soleus muscle, the opposite was detected in the muscle of the aged rats. [ABSTRACT FROM AUTHOR]

It has been shown that stretching exercises can improve the flexibility and independence of the elderly. However, although these exercises commonly constitute training programs, the morphological adaptations induced by stretching exercises in aged skeletal muscle are still unclear. Objective To assess the acute effects of passive mechanical static stretching on the morphology, sarcomerogenesis and modulation of important components of the extracellular matrix of the soleus muscle of aged female rats. Methods Fifteen old female rats with 26 months were divided into two groups: stretching ( n = 8, SG) and control ( n = 7, CG): The stretching protocol consisted of 4 repetitions each of 1 min with 30 s interval between sets. Stretching was performed on the left soleus muscle, 3 times a week for 1 week. After three sessions, the rats were anesthetized to remove the left soleus muscle, and then euthanized. The following analyses were carried out: muscle fiber cross-sectional area and serial sarcomere number; immunohistochemistry for the quantification of collagen I, III and TGFβ-1. Results a decrease in muscle fiber cross-sectional area of the SG was observed when compared to the CG ( p = 0.0001, Kruskal–Wallis); the percentage of type I collagen was significantly lower in the SG when compared to the CG ( p = 0.01, Kruskal–Wallis), as well as the percentage of TGFβ-1 ( p = 0.04, Kruskal–Wallis); collagen III was significantly higher in the SG than in the CG (7.06 ± 6.88% vs 4.92 ± 5.30%, p = 0.01, Kruskal–Wallis). Conclusion Although the acute stretching induced muscle hypotrophy, an antifibrotic action was detected. [ABSTRACT FROM AUTHOR]

• Gastrocnemius muscle thickness has correlation with calf circumference in older women. • Excess weight is a limitation condition when using gastrocnemius muscle thickness. • Gastrocnemius muscle thickness might be a complementary measure of calf circumference. Calf circumference (CC) is an indirect method used to evaluate muscle mass in older adults. Ultrasound has also been studied as a method for measuring muscle mass. Therefore, the aim of the present study was to correlate CC and muscle thickness of the medial gastrocnemius muscle (MGM) in healthy older women. A cross-sectional study was conducted with 74 healthy older women. The MGM thickness was evaluated using an ultrasound device (Logiq Book XP, General Electric®). The reference value for adequate CC was ≥ 31 cm. Weight and height were measured for the calculation of the body mass index (BMI), which was dichotomized as with or without excess weight based on the cutoff points recommended by the World Health Organization (1995) ; Lipschitz (1994) and the Pan-American Health Organization (2001). All participants were ≥ 64 years of age. Mean weight and height were 66.19 kg (SD: 10.48) and 1.55 m (SD: 0.06), respectively. Half of the participants had a BMI higher than 27.53 kg/m2. Moderate positive correlations were found between CC and MGM thickness (ρ = 0.432; p < 0.001), MGM thickness and weight (r = 0.422; p < 0.001) and between MGM thickness and BMI (r = 0.438; p < 0.001). However, the correlation between CC and MGM thickness was non-significant among the women with excess weight. A moderate positive correlation between MGM thickness and CC was found in healthy older women. However, this correlation was weak and non-significant among those with excess weight. [ABSTRACT FROM AUTHOR]