The synergism of high-intensity intermittent exercise and every-other-day intermittent fasting regimen on energy metabolism adaptations includes hexokinase activity and mitochondrial efficiency.

Visceral lipid accumulation, organ hypertrophy and a reduction in skeletal muscle strength are all signs associated with the severity of obesity-related disease. Intermittent fasting (IF) and high-intensity intermittent exercise (HIIE) are natural strategies that, individually, can prevent and help treat obesity along with metabolic syndrome and its associated diseases. However, the combinatorial effect of IF and HIIE on energetic metabolism is currently not well understood. We hypothesized that their combination could have a potential for more than strictly additive benefits. Here, we show that two months of every-other-day intermittent fasting regimen combined with a high-intensity intermittent exercise protocol (IF/HIIE) produced a synergistic effect, enhancing physical endurance (vs. control, HIIE and IF) and optimizing metabolic pathways of energy production in male Wistar rats. The IF/HIIE group presented enhanced glucose tolerance (vs. control, HIIE and IF), lower levels of plasma insulin (vs. control and HIIE), and a global activation of low Km hexokinases in liver (vs. control, HIIE and IF), heart (vs. control and HIIE) and skeletal muscle (vs. control, HIIE and IF). The IF/HIIE synergism, rather than a simply additive effect, is evidenced by increase in muscle mass and cross-section area, activation of the FoF1 ATP synthase, and the gain of characteristics suggestive of augmented mitochondrial mass and efficiency observed in this group. Finally, important reductions in plasma oxidative stress markers were present preferentially in IF/HIIE group. These findings provide new insights for the implementation of non-pharmaceutical strategies to prevent/treat metabolic syndrome and associated diseases.

Evaluation of redox profiles in exogenous subclinical hyperthyroidism at two different levels of TSH suppression.

OBJECTIVE: Evaluate the relationship between exogenous subclinical hyperthyroidism and oxidative stress through the analysis of the redox profile of patients with subclinical hyperthyroidism exogenous (SCH) grade I (TSH = 0.1 to 0.4 IU/mL) and grade II (TSH < 0.1 IU/mL). SUBJECTS AND METHODS: We analyzed 46 patients with SCH due to the use of TSH suppressive therapy with LT4 after total thyroidectomy along with 6 control euthyroid individuals (3M and 3W). Patients were divided into two groups, G1 with TSH ≥ 0.1-0.4 IU/mL (n = 25; and 7M 14W) and G2 with TSH < 0.1 IU/mL (n = 25; and 4M 21W). Venous blood samples were collected to measure the levels of markers for oxidative damage (TBARS, FOX and protein carbonylation), muscle and liver damage (CK, AST, ALT, GGT) and antioxidants (GSH, GSSG and catalase). RESULTS: Individuals in G2 showed a GSH/GSSG ratio ~ 30% greater than those in G1 (p = 0.004) and a catalase activity that was 4 times higher (p = 0.005). For lipid peroxidation, the levels measured in G2 were higher than both control and G1 (p = 0.05). No differences were observed for both protein carbonyl markers. G1 and G2 presented with greater indications of cell injury markers than the control group. CONCLUSION: TSH suppression therapy with LT4 that results in subclinical hyperthyroidism can cause a redox imbalance. The greater antioxidant capacity observed in the more suppressed group was not sufficient to avoid lipid peroxidation and cellular damage.

Evaluation of redox profiles in exogenous subclinical hyperthyroidism at two different levels of TSH suppression

ABSTRACT Objective: Evaluate the relationship between exogenous subclinical hyperthyroidism and oxidative stress through the analysis of the redox profile of patients with subclinical hyperthyroidism exogenous (SCH) grade I (TSH = 0.1 to 0.4 IU/mL) and grade II (TSH < 0.1 IU/mL). Subjects and methods: We analyzed 46 patients with SCH due to the use of TSH suppressive therapy with LT4 after total thyroidectomy along with 6 control euthyroid individuals (3M and 3W). Patients were divided into two groups, G1 with TSH ≥ 0.1-0.4 IU/mL (n = 25; and 7M 14W) and G2 with TSH < 0.1 IU/mL (n = 25; and 4M 21W). Venous blood samples were collected to measure the levels of markers for oxidative damage (TBARS, FOX and protein carbonylation), muscle and liver damage (CK, AST, ALT, GGT) and antioxidants (GSH, GSSG and catalase). Results: Individuals in G2 showed a GSH/GSSG ratio ~ 30% greater than those in G1 (p = 0.004) and a catalase activity that was 4 times higher (p = 0.005). For lipid peroxidation, the levels measured in G2 were higher than both control and G1 (p = 0.05). No differences were observed for both protein carbonyl markers. G1 and G2 presented with greater indications of cell injury markers than the control group. Conclusion: TSH suppression therapy with LT4 that results in subclinical hyperthyroidism can cause a redox imbalance. The greater antioxidant capacity observed in the more suppressed group was not sufficient to avoid lipid peroxidation and cellular damage.

The influence of exercise order on strength performance in post menopause women / A influência da ordem dos exercícios sobre o desempenho da força muscular em mulheres na pós-menopausa

OBJECTIVE: Verify the influence of different exercise orders on the performance of the number of maximal repetitions in older women. METHODS: Twelve older women (65.7 ± 5.6 years, 66.9 ± 9.5 kg, 1.56 ± 0.67 m, 27.4 ± 3.6 kg/m2) underwent four nonconsecutive visits and two different orders of Resistance Training. At the first visit, the volunteers were submitted to anamnesis, anthropometric evaluation and a 10RM test. On the second visit, a re-test of 10RM was performed. On the third and fourth visits, the volunteers performed two exercise sequences: sequence A: bench press, latissimus pulldown close grip, biceps curl, triceps extension; for sequence B the order was inverted. Performance was measured by the number of repetitions in each exercise. To determine differences in performance for sequence A vs. sequence B, repeated measures were performed by two-way ANOVA followed by the Tuckey post-hoc test. RESULTS: The number of repetitions of each exercise varied significantly for the bench press, biceps curl and triceps extension between the exercise sequences. CONCLUSIONS: The order of the exercises performed in a resistance training session can affect the performance in the number of repetitions in older women.

OBJETIVO: Verificar a influência de diferentes sequências de exercícios no desempenho do número de repetições máximas em mulheres idosas. MÉTODOS: Doze mulheres idosas (65,7 ± 5,6 anos, 66,9 ± 9,5 kg, 1,56 ± 0,67 m; 27,4 ± 3,6 kg/m2) foram submetidas a diferentes sequências de exercícios no Treinamento Resistido. Na primeira visita, as voluntárias foram submetidas à anamnese, avaliação antropométrica e teste de 10 RM. Na segunda visita, foi feito um re-teste de 10RM. Na terceira e quarta visita, as voluntárias realizaram as duas sequências: SEQ A - supino horizontal, puxador alto fechado, rosca bíceps e rosca tríceps e, SEQ B - a ordem foi inversa. O desempenho foi medido pelo número de repetições em cada exercício. A fim de verificar as diferenças nos dados obtidos no desempenho em diferentes sequências e séries, foram realizadas medidas repetidas pela ANOVA two-way seguido do teste post-hoc de Tuckey. RESULTADOS: Os resultados demonstraram que o número de repetições de cada exercício variou significativamente entre as sequências nos exercícios de supino horizontal, rosca bíceps e rosca tríceps. CONCLUSÕES: A ordem dos exercícios realizada em uma sessão de treinamento resistido pode afetar o desempenho no número de repetições em mulheres idosas.

Short-term consumption of Ilex paraguariensis extracts protects isolated hearts from ischemia/reperfusion injury and contradicts exercise-mediated cardioprotection.

Perfusion of hearts with extracts of Ilex paraguariensis (IP/mate) appears to reduce ischemia/reperfusion (I/R) injury. To determine if oral consumption of IP/mate can provide similar cardioprotection, short-term consumption was investigated alone or in association with exercise in rats. Animals were grouped into control (C), IP/mate consumption (M), exercise (E), and exercise with mate (E+M). M and E+M groups consumed IP/mate (1 g·kg-1 body weight in 1 mL water) by gavage. E and E+M groups swam 7× per week for 30 min carrying an additional 5% of body weight. After 1 week, hearts were tested ex vivo to measure left ventricle developed pressure (LVDP), systolic and end diastolic pressure (LVSP/LVEDP), maximum velocity of contraction and relaxation (dP/dt+ and dP/dt-) during I/R and infarction size. In addition, cardiac tissue was analyzed for oxidative stress by lipid peroxidation and protein carbonyl levels along with activity of catalase and superoxide dismutase (SOD). LVDP was higher in hearts from M and E groups as well as decreased infarction sizes than others. At the end of reperfusion, dP/dt+ was increased in E and M and dP/dt- was higher in M. LVSP was higher in M and E compared with C. Protein carbonyl and thiobarbituric acid reactive substances levels were higher in M while SOD activity was increased in E. No differences were observed in other activities. The results suggest that short-term consumption of IP/mate has protective effects on heart I/R injury similar to exercise, but the combination of these interventions appears to contradict the beneficial adaptations from exercise.

Oxidative stress and antioxidant biomarker responses after a moderate-intensity soccer training session.

The present study investigated the effects of a moderate-intensity soccer training session on the production of reactive oxygen species (ROS) and the antioxidant capacity in athletes along with the biomarkers creatine kinase and transaminases for lesions in muscle and liver cells. Twenty-two male soccer players participated in this study. Blood samples were collected 5 min before and after a moderate-intensity game simulation. The results showed a decrease in the concentration of reduced glutathione (GSH) from an elevation in the production of ROS that maintained the redox homeostasis. Although the session promoted an elevated energy demand, observed by an increase in lactate and glucose levels, damage to muscle and/or liver cells was only suggested by a significant elevation in the levels of alanine transaminase (ALT). Of the two biomarkers analysed, the results suggest that measurements of the ALT levels could be adopted as a method to monitor recovery in athletes.

Efeito do treinamento de força na potência muscular de membros inferiores de idosos coronariopatas / Effect of resistance training on muscular power of lower limbs of elderly with coronary artery disease

Introdução: A força e a potência muscular têm relação direta com a capacidade funcional de idosos. Objetivo: Verificar o efeito absoluto e relativo da potência muscular de membros inferiores em idosos portadores de doença arterial coronariana. Métodos: Dez homens sedentários participaram de 24 sessões de treinamento de força compostas por 2 séries de 6 a 8 repetições máximas e 1 minuto de intervalo. No início, os exercícios foram: meio agachamento, step, flexão plantar. E após: extensão e flexão dos joelhos, adução e abdução do quadril sentado. A potência muscular foi mensurada nos momentos: pré, após 12 e 24 sessões. Resultados: Após 24 sessões de treinamento de força foram encontrados aumentos na potência muscular absoluta (p< 0.0001) e relativa (p<0.0001; p<0.0001) em relação à condição pré-treinamento, respectivamente. Conclusão: Vinte e quatro sessões de treinamento de força parecem ser suficientes para aumentar a PM absoluta e relativa de idosos coronariopatas. (AU)

Introduction: Strength and muscle power have a direct relationship with functional capacity in elderly people. Objective: Verify absolute and relative gains in muscle power of lower limbs in elderly people with coronary artery disease. Methods: Ten untrained men subjects participated of 24 sessions of resistance training composed by 2 sets of 6 to 8 maximum repetitions and 1 minute rest interval. Initially, the exercises were: half squat, step up and plantar flexion. And after: leg extension, leg curl, seated hip adduction and seated hip abduction. The muscle power was measured at times: pre, post 12 and 24 sessions. Results: After 24 sessions of resistance training were found increases in absolute muscle power (p< 0.0001) and relative (p< 0.0001) regarding the condition pre-training, respectively. Conclusion: Twenty four sessions of resistance training appear to be sufficient to increase absolute and relative muscle power in elderly people with coronary artery disease. (AU)

Protein carbonyl levels correlate with performance in elite field hockey players.

Excess and incorrectly selected exercise can degrade athletic performance from an imbalance in redox homeostasis and oxidative stress, but well-planned training and nutrition can improve antioxidant capacity. The aim of the study was to investigate how nutrient intake could influence oxidative stress and cell lesion biomarkers after 5 days of training followed by a game. Blood was collected from 10 athletes at the start of training (basal), after training (pre-game), and postgame. Their acceleration capacity also was measured pre- and postgame. Blood analysis showed an increase in lactate concentration postgame (13%) and total antioxidant capacity increased both pre-game (13.1%) and postgame (12.7%), all in comparison with basal levels. An oxidative stress marker, protein carbonyl (PC), increased 3-fold over the course of the game, which correlated with a decreased acceleration (r = 0.749). For biomarkers of tissue damage, creatine kinase and aspartate transaminase (AST) increased postgame by 150% and 75%, respectively. The AST variation had a high negative correlation with energy and carbohydrate consumption and a moderate correlation with lipid and vitamin C intake. Protein intake had a positive but moderate correlation with reduced glutathione. The observed correlations suggest that nutritional monitoring can improve exercise physiological homeostasis and that PC serves as a good biomarker for oxidative stress and performance loss.

2,4-Dinitrophenol reduces the reactivity of Lys553 in the lower 50-kDa region of myosin subfragment 1.

2,4-Dinitrophenol (DNP) increases the affinity of myosin for actin and accelerates its Mg(2+)ATPase activity, suggesting that it acts on a region of the myosin head that transmits conformational changes to actin- and ATP-binding sites. The binding site/s for DNP are unknown; however similar hydrophobic compounds bind to the 50-kDa subfragment of the myosin head, near the actin-binding interface. In this region, a helix-loop-helix motif contains Lys553, which is specifically labeled with the fluorescent probe 6-[fluorescein-5(and 6)-carboxamido] hexanoic acid succinimidyl ester (FHS). This reaction is sensitive to conformational changes in the helix-loop-helix and the labeling efficiency was reduced when S1 was bound to actin, DNP or nucleotide analogs. The nucleotide analogs had a range of effects (PPi>ADP·AlF(4)(-)>ADP) irrespective of the open-closed state of switch 2. The greatest reduction in labeling was in the presence of actin or DNP. When we measured the effect of each ligand on the fluorescence of FHS previously attached to S1, only DNP quenched the emission. Together, the results suggest that the helix-loop-helix region is flexible, it is part of the communication pathway between the ATP- and actin-binding sites of myosin and it is proximal to the region of myosin where DNP binds.