Anderson Rech

Echo intensity is negatively associated with functional capacity in older women

Muscle quality is an important component of the functional profile of the elderly, and previous studies have shown that both muscle quantity and quality independently contribute to muscle strength of the elderly. This study aimed to verify the association between quadriceps femoris muscle quality, analyzed by specific tension and echo intensity (EI), and rate of torque development (RTD) of the knee extensor muscles with the functional performance in elderly active women. Forty-five healthy, active elderly women (70.28 ± 6.2) volunteered to participate in this study. Quadriceps femoris muscle thickness and EI were determined by ultrasonography. Knee extension isometric peak torque and RTD were obtained from maximal isometric voluntary contraction curves. The 30-s sit-to-stand-up (30SS) test and usual gait speed (UGS) test were applied to evaluate functional performance. Rectus femoris EI presented a significant negative correlation with 30SS (r = −0.505, P < 0.01), UGS (rs = −0.347, P < 0.05), and isometric peak torque (r = −0.314, P < 0.05). The quadriceps femoris EI correlated negatively with 30SS (r = −0.493, P < 0.01) and isometric peak torque (r = −0.409, P < 0.01). The EI of the quadriceps femoris and all quadriceps muscle portions significantly correlated with RTD. RTD significantly correlated with physical performance in both functional tests (30SS = r = 0.340, P < 0.05; UGS = rs = 0.371, P < 0.05). We concluded that muscle EI may be an important predictor of functional performance and knee extensor power capacity in elderly, active women.

Evidences that maternal swimming exercise improves antioxidant defenses and induces mitochondrial biogenesis in the brain of young Wistar rats

Physical exercise during pregnancy has been considered beneficial to mother and child. Recent studies showed that maternal swimming improves memory in the offspring, increases hippocampal neurogenesis and levels of neurotrophic factors. The objective of this work was to investigate the effect of maternal swimming during pregnancy on redox status and mitochondrial parameters in brain structures from the offspring. Adult female Wistar rats were submitted to five swimming sessions (30 min/day) prior to mating with adult male Wistar rats, and then trained during the pregnancy (five sessions of 30-min swimming/week). The litter was sacrificed when 7 days old, when cerebellum, parietal cortex, hippocampus, and striatum were dissected. We evaluated the production of reactive species and antioxidant status, measuring the activities of superoxide-dismutase (SOD), catalase (CAT) and glutathione-peroxidase (GPx), as well as non-enzymatic antioxidants. We also investigated a potential mitochondrial biogenesis regarding mitochondrion mass and membrane potential, through cytometric approaches. Our results showed that maternal swimming exercise promoted an increase in reactive species levels in cerebellum, parietal cortex, and hippocampus, demonstrated by an increase in dichlorofluorescein oxidation. Mitochondrial superoxide was reduced in cerebellum and parietal cortex, while nitrite levels were increased in cerebellum, parietal cortex, hippocampus, and striatum. Antioxidant status was improved in cerebellum, parietal cortex, and hippocampus. SOD activity was increased in parietal cortex, and was not altered in the remaining brain structures. CAT and GPx activities, as well as non-enzymatic antioxidant potential, were increased in cerebellum, parietal cortex, and hippocampus of rats whose mothers were exercised. Finally, we observed an increased mitochondrial mass and membrane potential, suggesting mitochondriogenesis, in cerebellum and parietal cortex of pups subjected to maternal swimming. In conclusion, maternal swimming exercise induced neurometabolic programing in the offspring that could be of benefit to the rats against future cerebral insults.

Metabolic effects of sulforaphane oral treatment in streptozotocin-diabetic rats.

Diabetes has reached epidemic levels in the whole world, and the use of bioactive compounds that may have the capacity to prevent and treat diabetes is of great interest. Sulforaphane (SFN) is a compound which is found in cruciferous vegetables and that acts as both a potent antioxidant and regulator of gene expression. The aim of this study was to evaluate the effect of SFN in diabetes induced by streptozotocin (STZ). Male Wistar rats were gavaged with water or 0.1, 0.25, or 0.5 mg/kg of SFN before an injection of STZ (80 mg/kg). Animals treated with SFN showed fasting glycemia, insulin sensitivity, and hepatic glycogen concentrations, similar to the control group (nondiabetic), and different from the diabetic group. Diabetic animals also presented elevated levels of serum triacylglycerols (TAG), urea, and creatinine, and all SFN doses were able to reverse these alterations. However, the same doses of SFN accentuated alterations in total cholesterol, alanine, and aspartate aminotransferase levels, and had no effect on hepatic TAG, HDL cholesterol, and uptake of 2-deoxy glucose in adipose tissue and soleum muscle. Based on the effects inferred by the present data, SFN presented some positive effects against diabetes induction, although the impairment of hepatic function and cholesterol levels were aggravated after treatment with the compound.

The effects of periodized concurrent and aerobic training on oxidative stress parameters, endothelial function and immune response in sedentary male individuals of middle age.

The vascular endothelium plays a key role in arterial wall homeostasis by preventing atherosclerotic plaque formation. A primary causal factor of endothelial dysfunction is the reactive oxygen species. Aerobic exercise is ascribed as an important adjuvant therapy in endothelium‐dependent cardiovascular disease. However, little is known about the effects of concurrent (aerobic + strength) training on that. For a comparison of the effects of aerobic and concurrent physical training on endothelial function, oxidative stress parameters and the immunoinflammatory activity of monocytes/macrophages, 20 adult male volunteers of middle age were divided into a concurrent training (CT) programme group and an aerobic training group. The glutathione disulphide to glutathione ratio (GSSG/GSH) and plasma lipoperoxide (LPO) levels, as well as flow‐mediated dilation (FMD), monocyte/macrophage functional activity (zymosan phagocytosis), body lipid profiles, aerobic capacity (maximal oxygen uptake) and strength parameters (one‐repetition maximum test), were measured before and after the exercise training programmes. The CT exhibited reduced acute effects of exercise on the GSSG/GSH ratio, plasma LPO levels and zymosan phagocytosis. The CT also displayed improved lipid profiles, glycaemic control, maximal oxygen uptake and one‐repetition maximum test values. In both the aerobic training and the CT, training improved the acute responses to exercise, as inferred from a decrease in the GSSG/GSH ratios. The aerobic sessions did not alter basal levels of plasma LPO or macrophage phagocytic activity but improved FMD values as well as lipid profiles and glycaemic control. In summary, both training programmes improve systemic redox status and antioxidant defences. However, the aerobic training was more efficient in improving FMD in the individuals studied. Copyright

Concurrent strength and endurance training exercise sequence does not affect neuromuscular adaptations in older men

Concurrent training is an effective method for increasing skeletal muscle performance in aging individuals, but controversy exists as to whether chronic neuromuscular and functional adaptations are affected by the intra-session exercise sequence. Therefore the aim of this study was to evaluate the effect of concurrent endurance and power-like strength training exercise sequence on muscular and functional adaptations of older participants. Thirty-six healthy older men not engaged in systematic exercise training programs for at least 6 months were divided into a control group (CON; 65.8±5.3 years), or in the training groups: endurance-strength (ES; 63.2±3.3 years), or strength-endurance (SE; 67.1±6.1 years). Training groups underwent 12 weeks of concurrent endurance and power-like strength training, starting every exercise session with either endurance (in ES) or strength (in SE) exercises. Measurements included knee extension one repetition maximum (1RM), knee extension power, 30 second sit-to-stand test (30SS), maximum vastus lateralis surface electromyographic activity, and rectus femoris echo intensity (RFEI). Significant increases in maximal strength (ES +18±11.3%; SE +14.2±6.0%; p≤0.05), peak power (ES +22.2±19.4%; SE +26.3±31.3%; p≤0.05), and 30SS performance (ES +15.2±7.2%; SE +13.2±11.8%; p≤0.05) were observed only in the training groups, with no differences between ES and SE. Maximum muscular activity was greater after 12weeks at training groups (p≤0.05), and reductions in RFEI were found only in ES and SE (p≤0.05). These results demonstrate that concurrent strength and endurance training performed twice a week effectively increases muscular performance and functional capacity in older men, independent of the intra-session exercise sequence. Additionally, the RFEI decreases indicate an additional adaptation to concurrent training.

Echo intensity independently predicts functionality in sedentary older men.

Introduction: The aim of this study was to examine the associations between quadriceps muscle functionality features in nonactive older men to determine predictors of functional performance. Methods: Quadriceps functional parameters, including quadriceps echo intensity (QEI), rate of torque development (RTD), and the 30 s sit‐to‐stand test (30SS), were assessed in 50 healthy sedentary older men (66 ± 5.4 years). RTD/QEI ratios were also calculated to identify the best predictor of functional performance. Results: 30SS performance was associated with RTD, muscle thickness, RTD‐50/QEI, RTD‐100/QEI, RTD‐50/QEI/WBM, and RTD‐100/QEI/WBM. A multiple stepwise linear regression demonstrated that QEI was the best single predictor of functional performance, explaining ∼30% of the 30SS variance. Conclusions: These results indicate that QEI was the strongest contributor to functionality of nonactive older men, suggesting that QEI may be an alternative tool for screening of muscle impairment that leads to decreased functional performance in this population. Muscle Nerve 55: 9–15, 2017

Neuromuscular Adaptations to Unilateral vs. Bilateral Strength Training in Women.

Abstract Botton, CE, Radaelli, R, Wilhelm, EN, Rech, A, Brown, LE, and Pinto, RS. Neuromuscular adaptations to unilateral vs. bilateral strength training in women. J Strength Cond Res 30(7): 1924–1932, 2016—Considering the bilateral deficit, the sum of forces produced by each limb in a unilateral condition is generally greater than that produced by them in a bilateral condition. Therefore, it can be speculated that performing unilateral strength exercises may allow greater training workloads and subsequently greater neuromuscular adaptations when compared with bilateral training. Hence, the purpose of this study was to compare neuromuscular adaptations with unilateral vs. bilateral training in the knee extensor muscles. Forty-three recreationally active young women were allocated to a control, unilateral (UG) or bilateral (BG) training group, which performed 2 times strength training sessions a week for 12 weeks. Knee extension one repetition maximum (1RM), maximal isometric strength, muscle electrical activity, and muscle thickness were obtained before and after the study period. Muscle strength was measured in unilateral (right + left) and bilateral tests. Both UG and BG increased similarly their unilateral 1RM (33.3 ± 14.3% vs. 24.6 ± 11.9%, respectively), bilateral 1RM (20.3 ± 6.8% vs. 28.5 ± 12.3%, respectively), and isometric strength (14.7 ± 11.3% vs. 13.1 ± 12.5%, respectively). The UG demonstrated greater unilateral isometric strength increase than the BG (21.4 ± 10.5% vs. 10.3 ± 11.1%, respectively) and only the UG increased muscle electrical activity. Muscle thickness increased similarly for both training groups. Neither group exhibited pretesting 1RM bilateral deficit values, but at post-testing, UG showed a significant bilateral deficit (−6.5 ± 7.8%) whereas BG showed a significant bilateral facilitation (5.9 ± 9.0%). Thus, performing unilateral or bilateral exercises was not a decisive factor for improving morphological adaptations and bilateral muscle strength in untrained women. Unilateral training, however, potentiate unilateral specific strength gains.

Dietary n-3 polyunsaturated fatty acids revert renal responses induced by a combination of 2 protocols that increase the amounts of advanced glycation end product in rats

Renal dysfunction is a severe complication that is caused by diabetes mellitus. Many factors associate the progression of this complication with high levels of proinflammatory and pro-oxidant substances, such as advanced glycation end products (AGEs), which form a heterogeneous group of compounds that can accumulate in tissues such as retinas, joints, and kidneys. The hypothesis of this study is that n-3 polyunsaturated fatty acids (n-3 PUFAs) have a nephroprotective effect on rats after exposing them to a combination of 2 protocols that increase the AGE amounts: a high-fat diet enriched with AGEs and a diabetes rat model. Adult Wistar rats were divided into 6 groups that received the following diets for 4 weeks: (1) control group; 2) HAGE: high AGE fat-containing diet group; (3) HAGE + n-3: high AGE fat-containing diet plus n-3 PUFAs group; (4) diabetic group; (5) Db + HAGE: high AGE fat-containing diet diabetic group; and (6) Db + HAGE + n-3: high AGE fat-containing diet plus n-3 PUFAs diabetic group. Diabetes mellitus was induced by an intraperitoneal injection of alloxan (150 mg kg(-1)). In diabetic and nondiabetic rats, the high HAGE fat-containing diet increased the serum creatinine, tumor necrosis factor-α, thiobarbituric acid reactive substances, and reactive oxygen species levels, as well as the superoxide dismutase/catalase + glutathione peroxidase ratio and the superoxide dismutase 2 and receptor for advanced glycation end products immunocontent of the kidneys. n-3 Polyunsaturated fatty acids attenuated these alterations and influenced the receptor for advanced glycation end products/oxidative stress/tumor necrosis factor-α axis. In summary, this study showed that the extrinsic AGE pathway (HAGE diet) had a greater effect on renal metabolism than the intrinsic AGE pathway (diabetes induction) and that n-3 PUFAs appear to prevent renal dysfunction via antioxidant and anti-inflammatory pathways.

Benefits of resistance training in physically frail elderly: a systematic review

AimExercise is one of the most important components in frailty prevention and treatment. Therefore, we systematically reviewed the effect of resistance training (RT) alone or combined with multimodal exercise intervention on muscle hypertrophy, maximal strength, power output, functional performance, and falls incidence in physically frail elderly.MethodsMEDLINE, Cochrane CENTRAL, PEDro, and SPORTDiscus databases were searched from 2005 to 2017. Studies must have mentioned the effects of RT (i.e., included or not in multimodal training) on at least one of the following parameters: muscle mass, muscle strength, muscle power, functional capacity, and risk of falls in frail elderly.ResultsThe initial search identified 371 studies and 16 were used for qualitative analysis for describing the effect of strength training performed alone or in a multimodal exercise intervention. We observed that RT alone or in a multimodal training may induce increases of 6.6–37% in maximal strength; 3.4–7.5% in muscle mass, 8.2% in muscle power, 4.7–58.1% in functional capacity and risk of falls, although some studies did not show enhancements.ConclusionFrequency of 1–6 sessions per week, training volume of 1–3 sets of 6–15 repetitions and intensity of 30–70%1-RM promoted significant enhancements on muscle strength, muscle power, and functional outcomes. Therefore, in agreement with previous studies, we suggest that supervised and controlled RT represents an effective intervention in frailty treatment.

The effects of strength, aerobic, and concurrent exercise on skeletal muscle damage in rats

Introduction: In this study we examined oxidative stress and skeletal muscle damage resulting from acute strength, aerobic, or concurrent exercise in rats. Methods: The animals were divided into control (C), strength (SE), aerobic (AE), and combined (CE) exercise groups. They were euthanized at 3 different time‐points (6, 24, and 48 h) after acute exercise. Results: SE exercise rats had increased dichlorofluorescein oxidation at 6 h post‐exercise and decreased superoxide dismutase activity at all time‐points. Glutathione peroxidase activity and sulfhydryl levels were increased in the AE group at 48 h post‐exercise. Serum lactate dehydrogenase activity was increased in the SE and CE groups at 24 h and in the AE group at 48 h. Echo intensity was elevated at 24 h for all groups. Conclusions: Forty‐eight hours was sufficient for complete recovery from oxidative stress and muscle damage in the SE and CE groups, but not in the AE group. Muscle Nerve 50: 79–86, 2014