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Different types of muscle contraction can cause different damage to the musculature and differences in inflammatory responses. Acute increases in circulatory inflammation markers can influence the crosstalk between coagulation and fibrinolysis processes, increasing the risk of thrombus formation and detrimental cardiovascular events. The aim of this study was to analyze the effects of concentric and eccentric exercise on hemostasis markers, C-reactive protein (CRP), and the relationship between these variables. Eleven healthy subjects with a mean age of 25.4 ± 2.8, non-smokers, with no history of cardiovascular disease and blood type O, randomly performed an isokinetic exercise protocol consisting of 75 concentric (CP) or eccentric (EP) contractions of knee extension, divided into five sets of 15 repetitions combined with 30-s rest. Blood samples for analysis of FVIII, von Willebrand factor, tissue plasminogen activator (t-PA), plasminogen activator inhibitor type-1 (PAI-1), and CRP were collected pre, post, 24 h, and 48 h after each protocol. Increased levels of CRP at 48 h in EP versus CP ( p = 0.002), increased PAI-1 activity 48 h in EP versus CP ( p = 0.044), and a reduction in t-PA at 48 h when compared with post-protocol in both protocols ( p = 0.001). A correlation was found between CRP and PAI-1 at 48 h of PE ( r2 = 0.69; p = 0.02). This study showed that both EP and CP increase the clotting process, albeit only the exercise performed eccentrically induces inhibition of fibrinolysis. This is possibly due to the increase in PAI-1 48 h after the protocol, which correlates with the increase in inflammation as demonstrated by the CRP levels.

Summary Objectives The aim of this study was to evaluate the effect of sixteen weeks of strength training on forearm blood flow (FBF) and nitric oxide (NO) production at rest induced by exercise in postmenopausal women. Equipment and methods Twenty postmenopausal sedentary women 60 ± 5 years participated in this study. The volunteers were randomly assigned into two groups: The trained group (TG, n = 10), performed 3 sessions of approximately 1 hour of strength exercise per week during 16 weeks, and the control group (CG, n = 10), did not perform the systematic physical activity. Forearm blood flow was measured by venous plethysmography and the measurements of nitric oxide production by Griess assay. The measurements were performed before and after training with subjects at rest and undergoing a protocol of handgrip. Results After strength training TG increased significantly FBF values after exercise (3.98 ± 1.81 vs. 2.37 ± 1.03 ml.100 ml−1.min−1; P

Background: In the literature, professions that impose body standards for daily performance are designated as non-conventional professions (i.e. models, athletes, ballet dancers), with great emphasis on the female population. More than a job, it becomes a lifestyle to those inserted in this environment, thus, thousands of children and adolescents seek the inclusion and success in these professions due to financial and media gains. Such professions are associated to several health-related risk factors. The purpose of this study was to identify whether there is a relationship between physical fitness levels, cardiometabolic health markers, mental health and dietary habits in non-conventional professions. Methods: The sample consisted of 41 female individuals aged between 14 and 24 years, divided in four groups, control group/ university students (UG=11), models (MG=11), ballet dancers (BG=11), and athletes group (AG=8). Physical fitness outcomes (cardiorespiratory fitness, flexibility, maximal dynamic strength, muscular endurance and body composition); biochemical outcomes (high density lipoprotein [HDL], low density lipoprotein [LDL], total cholesterol [TC], fasting glucose [FG], fasting insulin [FI], C-reactive protein [CRP]), diet quality and mental health were evaluated. Results: No impairments were observed in the health markers evaluated, both for health-related physical fitness and biochemical outcomes. Even with statistically significant differences between the groups for chronological age (p=0.002), menarche (p=0.004), career length (p=0.001), height (p=0.001), body mass index (p=0.018), waist-to-height ratio (p2peak (p=0.020), maximal dynamic strength of knee extensors (p=0.031) and elbow flexors (p=0,001) and flexibility (pConclusion: The professions analyzed do not seem to interfere in the physical and metabolic health of the girls assessed. However, regarding mental health, the evaluated age group was susceptible to depressive symptoms.

Background: Reduced glutathione (GSH) is one of the main thiols involved in antioxidant defense. Changes in circulatory levels of GSH during exercise are associated with hyperthermia and dehydration. The mechanisms by which these alterations occur are not entirely known. We hypothesize that erythrocytes could be an important source of circulatory GSH during heat stress conditions. We performed two separate experiments to address this hypothesis. Methods: In the first experiment, we sought to investigate the impact of exercise in the heat and dehydration on erythrocyte levels of GSH. A total of 10 men performed 60 min of cycling at 60% VO2peak in the heat (38.0 ± 0.9 °C) or in a control temperate environment (23.0 ± 1.0 °C), both with and without dehydration. Relative humidity ranged from 50 to 70%. Blood samples were taken before and after exercise to measure GSH and oxidized (GSSG) glutathione. In the second experiment, erythrocytes were isolated from blood samples taken at rest and heated in vitro to determine the impact of heat on erythrocyte glutathione content. Tubes with erythrocytes were exposed to water baths at different temperatures, one tube was exposed to a water bath at 35 °C and the other tube to a water bath at 41 °C for a period of 30 min. After exposure to heat, plasma and erythrocytes were extracted for GSH and GSSG analyses. Results: Dehydration decreased circulatory GSH, regardless of ambient temperature (temperate and heat decreased 15.35% and 30.31%, respectively), resulting in an altered redox balance. Heat increased GSH levels in vitro. Conclusion: Our data suggest that dehydration decreases circulatory GSH levels regardless of environmental temperature. In addition, in vitro data suggests that erythrocytes may contribute to the release of GSH during exposure to heat stress.

New finding What is the central question of this study? How does moderate-intensity aerobic exercise affect the behaviour of purinergic enzymes in sedentary, overweight and physically active subjects? What is the relationship between purinergic and inflammatory responses triggered by exercise? What is the main finding and its importance? Moderate-intensity aerobic exercise modifies the activity of purinergic enzymes and the levels of nucleotides and nucleosides. These results are similar in subjects with different biological characteristics. 5'-Nucleotidase activity and adenosine levels are associated with inflammatory responses. This study suggests that a purinergic pathway is related to the inflammatory responses triggered by exercise. Abstract Purinergic signalling is a mechanism of extracellular communication that modulates events related to exercise, such as inflammation and coagulation. Herein, we evaluated the effects of acute moderate-intensity exercise on the activities of purinergic enzymes and plasma levels of adenine nucleotides in individuals with distinct metabolic characteristics. We analysed the relationship between purinergic parameters, inflammatory responses and cardiometabolic markers. Twenty-four healthy males were assigned to three groups: normal weight sedentary (n = 8), overweight sedentary (n = 8) and normal weight physically active (n = 8). The volunteers performed an acute session of moderate-intensity aerobic exercise on a treadmill at 70% of V O 2 peak ; blood samples were drawn at baseline, immediately post-exercise and at 1 h post-exercise. Immediately post-exercise, all subjects showed increases in ATP, ADP, AMP and p-nitrophenyl thymidine 5'-monophosphate hydrolysis, while AMP hydrolysis remained increased at 1 h after exercise. High-performance liquid chromatography analysis demonstrated lower levels of ATP and ADP at post- and 1 h post-exercise in all groups. Conversely, adenosine and inosine levels increased at post-exercise, but only adenosine remained augmented at 1 h after exercise in all groups. With regard to inflammatory responses, the exercise protocol increased tumour necrosis factor α (TNF-α) and interleukin 8 (IL-8) concentrations in all subjects, but only TNF-α remained elevated at 1 h after exercise. Significant correlations were found between the activity of 5'-nucleotidase, adenosine levels, V O 2 peak , triglyceride, TNF-α and IL-8 levels. Our findings suggest a purinergic signalling pathway that participates, at least partially, in the inflammatory responses triggered by acute moderate-intensity exercise. The response of soluble nucleotidases to acute moderate exercise appears to be similar between subjects of different biological profiles.

Summary Background Zumba is an alternative type of dance-exercise for improving fitness and cardiovascular risk in women. However, the aerobic training intensity of Zumba for healthy adult women is unclear. Objective To describe heart rate (HR), lactate and energy-expenditure during a Zumba class, relating them to participants’ second ventilatory threshold (VT2). Comparisons were performed with a low-to-moderate intensity aerobic exercise session (walking/running). Methods Ten healthy women (28 ± 3.2 yrs, BMI 25.3 ± 2.7) were examined on three occasions, in a randomized cross-over study: preliminary tests (body composition/aerobic fitness), session 1 (Zumba), and session 2 (aerobic exercise, 65% HRreserve). Fingertip blood samples were taken pre, at 25 min, and post exercise sessions. HR was continuously measured. VT2 was determined from the HR deflection point obtained during a maximum effort test. Results Zumba presented higher HR percentage of VT2 (95.3%) than walking (86%). Lactate concentration (mmol.L−1) of Zumba (10.9 ± 3.4) was superior to aerobic exercise (6.9 ± 3.6) at 25 min, also post-exercise. Both Zumba and aerobic exercise increased lactate responses at 25 min and post-exercise, when compared to rest. Energy-expenditure of Zumba (573.9 ± 100.3) was superior to aerobic exercise (260.4 ± 63.8). Conclusion Exercise intensity of Zumba was superior to low-intensity aerobic exercise, with HR and lactate responses corresponding to participants’ VT2. This suggests that Zumba may be used as a promising way of increasing levels of physical activity at moderate-vigorous intensity, enhancing cardiovascular fitness and reducing CVR in health adult women.