Influence of age on postural control during dual task: a centre of pressure motion and electromyographic analysis.

BACKGROUND: Dual task influences postural control. A cognitive task seems to reduce muscle excitation during a postural balance, especially in older adults (OA). AIM: The aim of this study is to evaluate the effect of three cognitive tasks on muscle excitation and static postural control in OA and young adults (YA) in an upright posture maintenance task. METHODS: 31 YA and 30 OA were evaluated while performing a modified Romberg Test in five different conditions over a force plate: open eyes, closed eyes, spatial-memory brooks' test, counting backwards aloud test and mental arithmetic task. The surface electromyographic signals of Tibialis anterior (TA), Lateral Gastrocnemius (GL), Peroneus Longus (PL), and Erector Spinae (ES) was acquired with an 8-channel surface electromyographic system. The following variables were computed for both the electromyographic analysis and the posturographic assessment: Root mean square (RMS), centre of pressure (CoP) excursion (Path) and velocity, sway area, RMS of the CoP Path and 50%, 95% of the power frequency. Mixed ANOVA was used to detect differences with group membership as factor between and type of task as within. The analysis was performed on the differences between each condition from OE. RESULTS: An interaction effect was found for Log (logarithmic) Sway Area. A main effect for task emerged on all posturographic variables except Log 95% frequencies and for Log PL and ES RMS. A main effect for group was never detected. DISCUSSION AND CONCLUSION: This study indicates a facilitating effect of mental secondary task on posturographic variables. Non-silent secondary task causes increase in ES and TA muscle activation and a worsening in static postural control performance.

Exercise prescription and tailored physical activity intervention in onco-hematology inpatients, a personalized bedside approach to improve clinical best practice.

Therapy of hematological malignancies lasts for long periods implicating various complications. The chemotherapy induces fatigue and forces bed rest. These features strongly contribute to a general impairment of the physical efficiency. Oppositely, an increase of physical exercise can prevent or reduce this weakening. Few trials examined the efficacy of an exercise in onco-hematological inpatients, during their hospitalization. Therefore, this study aimed to determine the feasibility of an inter-hospital intervention and the beneficial role of a tailored exercise program in the maintenance of the physical function in onco-hematological inpatients. The study included 42 patients, which were allocated in two groups. In the intervention group (IG) a tailored exercise protocol during patient's hospitalization was administered. Exercise protocol was focused on development of strength, balance control, and flexibility; sessions were directly performed in the patient's hospital room everyday for 15 to 30 minutes. Exercise was supervised by an exercise specialist and driven by a multimedia support. Control group (CG) remained physically inactive for all period of hospitalization. To examine the interaction between the two situations (T0 and T1 ) and the two groups (IG and CG) for all dependent variables, a 2 × 2 within-subjects contrasts model analysis of variance was applied. Within groups analysis displayed significant differences in grip and leg strength and in static balance control (P < 0.05) with medium to very large effect size. Results from this investigation showed that a tailored exercise protocol administered to hospitalized onco-hematological patients was feasible and efficient to promote the maintenance of their physical function, improving clinical best practice including exercise to the traditional treatment. Moreover, the magnitude of the difference between the IG and the CG underlined the importance to invite and stimulate patients to workout to preserve the physical function, counteracting side effects of chemotherapy treatments with a concurrent reduction in bed rest syndrome.

Randomized, blinded, controlled trial on effectiveness of photobiomodulation therapy and exercise training in the fibromyalgia treatment.

This study evaluated the role of the phototherapy and exercise training (EXT) as well as the combined treatment in general symptoms, pain, and quality of life in women suffering from fibromyalgia (FM). A total of 160 women were enrolled and measures were carried out in two sets: it was sought to identify the acute effect for a single phototherapy and EXT session (Set 1); long-term effect (10 weeks) of the interventions (Set 2). Phototherapy irradiation was performed at 11 locations in their bodies, employing a cluster with nine diodes (one super-pulsed infrared 905 nm, four light-emitting diodes [LEDs] of 640 nm, and four LEDs of 875 nm, 39.3 J per location). Algometry and VAS instrument were applied to evaluate pain. The FM symptoms were evaluated with Fibromyalgia Impact Questionnaire (FIQ) and Research Diagnostic Criteria (RDC) instruments. Quality of life was assessed through SF-36 survey. Set 1: pain threshold was improved with the phototherapy, and EXT improved the pain threshold for temporomandibular joint (right and left body side) and occipital site (right body side). Set 2: there was improved pain threshold in several tender points with the phototherapy and EXT. There was an overlap of therapies to reduce the tender point numbers, anxiety, depression, fatigue, sleep, and difficulty sleeping on FIQ/RDC scores. Moreover, quality of life was improved with both therapies. The phototherapy and EXT improved the pain threshold in FM women. A more substantial effect was noticed for the combined therapy, in which pain relief was accomplished by improving VAS and FIQ scores as well as quality of life.

Predicted Equation for VO2 Based on a 20-Meter Multistage Shuttle Run Test for Children.

This study compared maximum oxygen consumption (VO2max) on a 20-meter multistage shuttle run test (20-Srt) with a cardiopulmonary exercise test (CPET) to determine a VO2max prediction equation for a 20-Srt in children aged 6-10 years. Eighty healthy children performed the CPET on a treadmill, while the 20-Srt took place on a sports court. Heart rate (HR) was measured and the expired gases were continuously measured breath-by-breath using a portable gas analyzer. The VO2max was lower (p<0.05) in CPET than 20-Srt for all, female, and male participants, respectively (46.3±7.9 vs. 48.7±4.6; 42.7±7.8 vs. 46.7±4.8; 49.3±6.8 vs. 50.4±3.9, mL·kg-1·min-1). The standard error estimates were between 3.0 and 3.6 and considered as not clinically relevant if less than 5 mL·kg-1·min-1. The intraclass correlation coefficient between the VO2 in CPET and in 20-Srt was 0.74 (CI95% 0.55-0.84) and considered moderately reliable. The linear multiple regression excluded sex, body mass index and fat-free mass and retained the maximum speed and age in the predictive equation. The 20-Srt estimates the VO2max with moderate reliability and the predictive equation was VO2maxpred=4.302+(maximum speed*5.613)-(age*1.523) for children aged 6-10 years.

Protective effects of photobiomodulation against resistance exercise-induced muscle damage and inflammation in rats.

We investigated whether low-level laser therapy (LLLT) prior to or post resistance exercise could attenuate muscle damage and inflammation. Female Wistar rats were assigned to non-LLLT or LLLT groups. An 830-nm DMC Laser Photon III was used to irradiate their hind legs with 2J, 4J, and 8J doses. Irradiations were performed prior to or post (4J) resistance exercise bouts. Resistance exercise consisted of four maximum load climbs. The load work during a resistance exercise bout was similar between Control (non-LLLT, 225 ± 10 g), 2J (215 ± 8 g), 4J (210 ± 9 g), and 8J (226 ± 9 g) groups. Prior LLLT did not induce climbing performance improvement, but exposure to 4J irradiation resulted in lower blood lactate levels post-exercise. The 4J dose decreased creatine kinase and lactic dehydrogenase levels post-exercise regardless of the time of application. Moreover, 4-J irradiation exposure significantly attenuated tumor necrosis factor alpha, interleukin-6, interleukin-1ß, cytokine-induced neutrophil chemoattractant-1, and monocyte chemoattractant protein-1. There was minor macrophage muscle infiltration in 4J-exposed rats. These data indicate that LLLT prior to or post resistance exercise can reduce muscle damage and inflammation, resulting in muscle recovery improvement. We attempted to determine an ideal LLLT dose for suitable results, wherein 4J irradiation exposure showed a significant protective role.

Dexamethasone-induced cardiac deterioration is associated with both calcium handling abnormalities and calcineurin signaling pathway activation.

Dexamethasone is a potent and widely used anti-inflammatory and immunosuppressive drug. However, recent evidences suggest that dexamethasone cause pathologic cardiac remodeling, which later impairs cardiac function. The mechanism behind the cardiotoxic effect of dexamethasone is elusive. The present study aimed to verify if dexamethasone-induced cardiotoxicity would be associated with changes in the cardiac net balance of calcium handling protein and calcineurin signaling pathway activation. Wistar rats (~400 g) were treated with dexamethasone (35 µg/g) in drinking water for 15 days. After dexamethasone treatment, we analyzed cardiac function, cardiomyocyte diameter, cardiac fibrosis, and the expression of proteins involved in calcium handling and calcineurin signaling pathway. Dexamethasone-treated rats showed several cardiovascular abnormalities, including elevated blood pressure, diastolic dysfunction, cardiac fibrosis, and cardiomyocyte apoptosis. Regarding the expression of proteins involved in calcium handling, dexamethasone increased phosphorylation of phospholamban at threonine 17, reduced protein levels of Na+/Ca2+ exchanger, and had no effect on protein expression of Serca2a. Protein levels of NFAT and GATA-4 were increased in both cytoplasmic and nuclear faction. In addition, dexamethasone increased nuclear protein levels of calcineurin. Altogether our findings suggest that dexamethasone causes pathologic cardiac remodeling and diastolic dysfunction, which is associated with impaired calcium handling and calcineurin signaling pathway activation.

Aerobic exercise training improves oxidative stress and ubiquitin proteasome system activity in heart of spontaneously hypertensive rats.

The activity of the ubiquitin proteasome system (UPS) and the level of oxidative stress contribute to the transition from compensated cardiac hypertrophy to heart failure in hypertension. Moreover, aerobic exercise training (AET) is an important therapy for the treatment of hypertension, but its effects on the UPS are not completely known. The aim of this study was to evaluate the effect of AET on UPS's activity and oxidative stress level in heart of spontaneously hypertensive rats (SHR). A total of 53 Wistar and SHR rats were randomly divided into sedentary and trained groups. The AET protocol was 5×/week in treadmill for 13 weeks. Exercise tolerance test, non-invasive blood pressure measurement, echocardiographic analyses, and left ventricle hemodynamics were performed during experimental period. The expression of ubiquitinated proteins, 4-hydroxynonenal (4-HNE), Akt, phospho-Akt(ser473), GSK3ß, and phospho-GSK3ß(ser9) were analyzed by western blotting. The evaluation of lipid hydroperoxide concentration was performed using the xylenol orange method, and the proteasomal chymotrypsin-like activity was measured by fluorimetric assay. Sedentary hypertensive group presented cardiac hypertrophy, unaltered expression of total Akt, phospho-Akt, total GSK3ß and phospho-GSK3ß, UPS hyperactivity, increased lipid hydroperoxidation as well as elevated expression of 4-HNE but normal cardiac function. In contrast, AET significantly increased exercise tolerance, decreased resting systolic blood pressure and heart rate in hypertensive animals. In addition, the AET increased phospho-Akt expression, decreased phospho-GSK3ß, and did not alter the expression of total Akt, total GSK3ß, and ubiquitinated proteins, however, significantly attenuated 4-HNE levels, lipid hydroperoxidation, and UPS's activity toward normotensive group levels. Our results provide evidence for the main effect of AET on attenuating cardiac ubiquitin proteasome hyperactivity and oxidative stress in SHR rats.

Effects of low level laser therapy on attachment, proliferation, and gene expression of VEGF and VEGF receptor 2 of adipocyte-derived mesenchymal stem cells cultivated under nutritional deficiency.

Low-level laser therapy (LLLT) has been shown to increase the proliferation of several cell types. We evaluated the effects of LLLT on adhesion, proliferation, and gene expression of vascular endothelial growth factor (VEGF) and type 2 receptor of VEGF (VEGFR2) at mesenchymal stem cells (MSCs) from human (hMSCs) and rat (rMSCs) adipose tissues on nutritional deficiencies. A dose-response curve was performed with cells treated with laser Ga-Al-As (660 nm, 30 mW) at energy of 0.7 to 9 J. Cell adhesion and proliferation were quantified 20, 40, and 60 min after LLLT and 24, 72, and 120 h after cultivation. Gene expression was verified by RT-PCR after 2 h of LLLT. A minor nutritional support caused a significant decrease in proliferation and adhesion of hMSCs and rMSCs. However, at the lowest LLLT dose (0.7 J), we observed a higher proliferation in hMSCs at standard condition shortly after irradiation (24 h). Adhesion was higher in hMSCs cultivated in controlled conditions at higher LLLT doses (3 and 9 J), and rMSCs show a reduction in the adhesion on 1.5 to 9 J. On nutritional deprivation, a 9 J dose was shown to reduce proliferation with 24 h and adhesion to all culture times in rMSCs. VEGF and VEGFR2 were increased after LLLT in both cell types. However, hMSCs under nutritional deprivation showed higher expression of VEGF and its receptor after irradiation with other laser doses. In conclusion, LLLT on human and rat MSCs might upregulate VEGF messenger RNA (mRNA) expression and modulate cell adhesion and proliferation distinctively.

Test-retest reliability and agreement of remote home-based functional capacity self-administered assessments in community-dwelling, socially isolated older adults.

Objectives: To determine the test-retest reliability and agreement of home-based functional capacity self-administered assessments in socially isolated older adults. Methods: Fourteen community-dwelling older adults (eight females, 67.9 ± 7.7 years) volunteered for this study. Before testing, participants were screened online for eligibility and received instructional videos explaining test set-up and execution. Participants underwent the 30-second sit-to-standing test, gait speed tests at the usual pace, and timed-up-and-go tests administered 4 weeks apart. For the 30-second sit-to-standing protocol, participants were instructed to repeatedly sit and stand from a chair (with a height of ∼ 43 cm and without armrests) for 30 s, with the number of repetitions recorded. In the gait speed test protocol, participants were instructed to walk at their usual and comfortable pace, with the time taken recorded (seconds). In the timed-up-and-go, participants stood up from a chair, walked as fast as possible for 3 m, circled a marked point, and returned to the chair to sit down, completing the test, with the score recorded (seconds). A trained researcher conducted the scoring virtually via synchronous video. Results: 30-second sit-to-standing, gait speed test, and timed-up-and-go showed excellent mean coefficient of variation values (2.0-4.9), small standard error of measurement (0.08-1.27), excellent intraclass coefficient (0.97-0.99), very strong correlations (0.97-0.99) and good agreement between the two days of testing. Conclusion: Self-administered functional capacity tests performed by older adults at home were reliable with good agreement. Healthcare professionals and older adults should take advantage of simple remote self-administered assessments performed at home to evaluate older adults' health status.

EFFECTS OF TREADMILL GAIT TRAINING ON BALANCE IN PARKINSON'S PATIENTS AFTER DEEP BRAIN STIMULATION.

Objective: After deep brain stimulation (DBS), patients with Parkinson's disease (PD) typically still present significant gait and postural stability problems, and thus additional interventions are needed. In this way, our purpose was evaluate the comparative effectiveness of treadmill training, with and without body weight support, on balance outcomes among patients with PD after DBS. Methods: Eleven patients with PD that were using bilateral subthalamic nucleus DBS were evaluated using Time Up and Go test (TUG); Berg Balance Scale (BBS) and Static Posturography. In phase 1, all subjects participated in 8-weeks of treadmill training in conjunction with conventional physiotherapy. After six weeks (wash-out), each patient then participated in a subsequent 8-weeks of treadmill training with partial body weight support. Results: After the phase 1, there were improvements on the cognitive TUG performance (Before: 15.7 ± 1,8 sec; After: 13.7 ± 3.1 sec; p < 0.01) and an increase of anteroposterior and medio-lateral body oscillation with eyes closed. After the phase 2, there were improvements in conventional (Before: 12.3 ± 2.0 sec; After: 10.7 ± 1.7 sec; p < 0.01) and cognitive (Before: 14.6 ± 3.5 sec; After: 12.5 ± 1.6 sec; p < 0.05) TUG performances. There were no significant changes in the Berg Balance Scale following either training protocol. Conclusion: Both trainings improved static and dynamic balance and had similar results; however, supported treadmill training seemed to be a potentially superior option, as patients tended to feel safer. Level of Evidence II, therapeutic studies - investigation of treatment outcomes.

Objetivo: Mesmo após a estimulação cerebral profunda (ECP), os pacientes com doença de Parkinson (DP) muitas vezes ainda apresentam problemas significativos de marcha e estabilidade postural, e, portanto, intervenções adicionais são necessárias. Avaliar a eficácia comparativa do treinamento em esteira, com e sem suporte de peso corporal, nos resultados de equilíbrio de pacientes com DP após ECP. Métodos: Onze pacientes com DP em uso de ECP bilateral do núcleo subtalâmico foram avaliados pelos testes Time Up and Go (TUG), escala de equilíbrio de Berg (EEB) e posturografia estática. Na fase 1, todos participaram de oito semanas de treinamento em esteira em conjunto com fisioterapia convencional. Após seis semanas (wash-out), cada paciente participou de oito semanas subsequentes de treinamento em esteira com suporte parcial de peso corporal. Resultados: Depois da fase 1, houve melhora no desempenho cognitivo do TUG (antes: 15,7 ± 1,8 s; depois: 13,7 ± 3,1 s; p < 0,01) e aumento da oscilação anteroposterior e médio-lateral do corpo com os olhos fechados. Após a fase 2, os resultados do TUG convencional (antes: 12,3 ± 2,0 seg; depois: 10,7 ± 1,7 seg; p < 0,01) e cognitivo (antes: 14,6 ± 3,5 s; depois: 12,5 ± 1,6 s; p < 0,05) demonstraram melhora. Os protocolos de treinamento não causaram mudanças significativas na EEB.. Conclusão: Ambos os treinos melhoraram o equilíbrio estático e dinâmico e tiveram resultados semelhantes; no entanto, o treinamento em esteira com suporte é uma opção potencialmente superior, uma vez que os pacientes tendiam a se sentir mais seguros. Nível de Evidência II, estudos terapêuticos - investigação de resultados de tratamento.

From surgery to functional capacity: muscle strength modifications in women post sleeve gastrectomy.

BACKGROUND: Severe obesity is characterized by excessive accumulation of fat generating a general health decline. Multidisciplinary treatment of obesity leads to significant weight loss in a few patients; therefore, many incur bariatric surgery. The main purpose of the study is to evaluate changes in functional capacity of people with obesity undergoing bariatric surgery and, in parallel, to correlate pre-surgery functional capacity with weight loss to improve exercise prescription during pre-operatory stage. METHODS: sixty women with diagnosed obesity were included. Maximal oxygen consumption, upper and lower limb strength and level of physical activity were recorded 1 month before and 6 months after sleeve gastrectomy. RESULTS: significant reduction on body weight (-30.1 kg) and Body Mass Index (-11.4 kg/m2) were highlighted after surgery. Absolute grip strength decreased significantly (-1.1 kg), while body weight normalized grip and lower limb strength increased significantly. The level of physical activity increased especially in leisure time (+ 593 METs/week) and active transport (+ 189.3 METs/week). Pre-surgery BMI and age predicted the amount of weight loss after surgery. CONCLUSIONS: Sleeve gastrectomy induces a reduction of muscle strength despite the increase of time spent in physical activity. Further research is necessary to integrate these results with data on body composition, and objective evaluation of physical activity level to define useful information for exercise prescription in terms of surgery pre-habilitation. TRIAL REGISTRATION: Padova University Hospital Board (protocol n. 2027 dated January 12, 2017).

Is physical inactivity and sedentary behavior associated with tumor stage in breast cancer patients? A cross-sectional study of Brazilian women.

OBJECTIVE: A comparative analysis of the association between sedentary behavior versus physical activity levels and tumor staging in women with breast cancer. METHODS: The present research adopted a cross-sectional study design to recruit a total of 55 adult and elderly women newly diagnosed with breast cancer for data collection and analysis. Inclusion criteria involved patients in procession of a formal approval for participation in the study by the treating physician and those not hitherto subjected to the first cycle of chemotherapy. RESULTS: Physical activity levels did not influence the pathological stage of breast cancer (p=0.26) or histological tumor grade (p=0.07) in the analyzed subjects. However, there was a significant association between physical activity levels and responsiveness to hormones (epidermal growth factor receptor (HER2), p<0.05) in the analyzed subjects. Significant difference was detected in the histological tumor grade in relation to the mean time spent sitting during the weekend (p<0.05). However, sedentary behavior had no influence on the tumor stage (p>0.05). CONCLUSION: Physical activity levels did not influence the tumor stage and histological tumor grade. Sedentary behavior had a significant influence on the histological tumor grade.

Muscle strength, aerobic capacity, and exercise tolerance are impaired in left ventricular assist devices recipients: A pilot study.

Background: Left ventricular assist devices (LVAD) are increasingly being used as a therapy for advanced heart failure, both as a bridge to heart transplant and, given the rapid advances in the LVAD's functionality and safety, and constant lack in availability of donor organs, as long-term destination therapy. With the diffusion of such therapy, it is crucial to assess patients' muscle strength, aerobic capacity and exercise tolerance, to improve their functional capacity. Methods: 38 LVAD recipients (33 men and five women) were included. Exercise testing including a maximal cardiopulmonary exercise test (CPET), handgrip, isometric and isokinetic strength testing of knee and ankle flexion/extension, and Romberg balance test in three conditions (eyes open, eyes closed, double task). Given the small and heterogeneous final sample size, a mostly descriptive statistical approach was chosen. Results: 12 participants were classified as "Obese" (BMI>29.9). The most common comorbidities were type II diabetes and chronic kidney disease. Only 12 participants were able to successfully complete all the assessments. CPET and isokinetic strength trials were the least tolerated tests, and the handgrip test the best tolerated. Mean VO2 peak was 12.38 ± 3.43 ml/kg/min, with 15 participants below 50% of predicted VO2 max, of which 6 below 30% VO2max. Mean handgrip strength was 30.05 ± 10.61 Kg; 25 participants were below the 25° percentile of their population's normative reference values for handgrip strength, 10 of which were below the 5° percentile. Issues with the management of the external pack of the LVAD and its influence on the test limited the validity of the balance tests data, therefore, no solid conclusions could be drawn from them. VO2 peak did not correlate with handgrip strength or with any of the lower limb strength measures. Conclusion: LVAD recipients show greatly reduced functional capacity and tolerance to exercise and exercise testing, with low overall strength levels. As strength variables appear to be independent from VO2 peak, different lower limbs strength tests should be explored to find a tolerable alternative in this population, which is subjected to muscle wasting due to old age, reduced tissue perfusion, side effects from the pharmacological therapies, and prolonged periods of bedrest.

Short-Term Effects of Land-Based Versus Water-Based Resistance Training Protocols on Post-Exercise Hypotension in Normotensive Men: A Crossover Study.

Considering that water immersion may acutely reduce blood pressure (BP) and that exercise may elicit positive post-exercise hypotension (PEH) responses, we aimed to analyze the presence of PEH in normotensive individuals and compare its magnitude between two resistance training sessions performed in aquatic or land environments. Ten physically active men (23.2 ± 3.1 years) performed the two training protocols in a randomized, counterbalanced fashion. BP measurements were performed for 30 min (at 5 min intervals) both prior to (resting) and after each of the protocols. No differences were observed between protocols at baseline (p > 0.05). Only the water-based resistance training protocol resulted in a systolic BP reduction from 10 to 20 min post-exercise (all p < 0.05) compared to baseline. Compared to the land-based session, systolic BP was lower in the water-based protocol from 10 to 25 min post-exercise (all p < 0.05). On the other hand, diastolic BP showed a similar PEH effect between water and land-based protocols for the entire 30 min post-session period (all p < 0.001). Our results suggest that water-based resistance training holds the potential as a nonpharmacological strategy to lower BP levels following exercise.

Stress level and heart rate variability in police post-occurrence of bank robbery: an experience report.

Introduction: The expectation of armed confrontation is among the most stressful elements in police work. Knowledge about perceived stress and cardiovascular markers in police officers comes from simulations. However, to date, information about psychophysiological responses during high-risk occurrences is scarce. Objectives: To assess stress levels and heart rate variability in policemen before and afer atending a bank robbery. Methods: Elite police officers (30.4 ± 3.7yrs) filled in a stress questionnaire and had their heart rate variability monitored at the beginning (7:00 am) and at the end (7:00 pm) of a work shif. At about 5:30 pm, these policemen were called to respond to a bank robbery in progress. Results: No significant changes in sources or symptoms of stress were found between before and afer the incident. However, statistical reductions were found in heart rate range interval (R-R interval [-13.6%]), pNN50 (-40.0%), and low frequency (-28%) and the low frequency/high frequency ratio increased (200%). These results suggest that although no change in the level of perceived stress was found, a significant reduction in heart rate variability may be atributed to a reduction in activation of the parasympathetic system. Conclusions: The expectation of armed confrontation is among the most stressful occurrences in police work. Research knowledge about perceived stress and cardiovascular markers in police officers comes from simulations. Data on psychophysiological responses post-occurrence of high-risk scenarios are scarce. This research may help law enforcement organizations find means to monitor police officers' acute stress levels afer any high-risk occurrences.

Introdução: No trabalho policial, a expectativa do confronto armado está entre as ocorrências mais estressantes. O conhecimento sobre as alterações dos níveis de estresse e marcadores cardiovasculares são oriundas de condições simuladas. Até o momento, a descrição das reações psicofsiológicas após ocorrência de alto risco são escassas. Objetivos: Verificar o nível de estresse e a variabilidade da frequência cardíaca em policiais após uma ocorrência de roubo a banco. Métodos: Oito policiais de elite (30,4±3,7 anos) preencheram um questionário de estresse e tiveram sua variabilidade da frequência cardíaca monitoradas no início (7h) e no final (19h) do turno de trabalho. Entretanto, por volta das 17h30, esses policiais atenderam uma ocorrência de roubo a banco. Resultados: Não foram encontradas alterações significantes entre o início e o final do plantão para as fontes e sintomas de estresse. Entretanto, houve redução significante para o intervalo da variação de frequência cardíaca [intervalo R-R (-13.6%)], pNN50 (-40.0%), baixa frequência (-28%) e aumento para razão baixa frequência/alta frequência (+200%). Dessa forma, nossos resultados sugerem que embora nenhuma mudança no nível de estresse percebido tenha sido encontrada, uma redução importante na variabilidade da frequência cardíaca pode ser atribuída a uma redução na ativação do sistema parassimpático. Conclusões: A associação de indicadores qualitativos e quantitativos (questionário e variabilidade da frequência cardíaca) contribui para um melhor entendimento de como gerenciar e treinar as habilidades emocionais dos policiais. Esta pesquisa pode ajudar as organizações de aplicação da lei a encontrar propostas para monitorar os níveis de estresse agudo dos policiais após qualquer ocorrência de alto risco.

The Role of Facebook® in Promoting a Physically Active Lifestyle: A Systematic Review and Meta-Analysis.

BACKGROUND: it is well known in literature that sedentary lifestyle contributes to worsening people's health. This issue highlights the need for effective interventions to promote an active lifestyle. Research suggested multilevel intervention strategies to promote adherence to recommended physical activity levels, including the use of social networks that may simplify access to health notions. Being Facebook® the most extensive worldwide social network, this document aimed to analyze the current body of evidence on the role of Facebook® in the promotion of physical activity. METHODS: eighteen manuscripts were considered eligible for this systematic review, and it was performed a meta-analysis (PRISMA guidelines) for overall physical activity parameters in eleven out of eighteen studies. RESULTS: significant improvements were detected in the total amount of physical activity. In parallel, an increase in other parameters, such as cardiovascular, body composition, and social support, were found. The aerobic training, with supervised and tailored modalities, showed more considerable improvements. CONCLUSIONS: this study showed that Facebook® might be considered a feasible and accessible approach to promoting regular exercise practice and achieving health benefits indicators. Future research on the cross-link between physical activity and social network management could also focus on strength training to verify if a more structured intervention would show an effect.

Resistance to obesity prevents obesity development without increasing spontaneous physical activity and not directly related to greater metabolic and oxidative capacity.

There are evidence that obese-resistant animals are more physically active, due to a higher rate of lipid oxidation. Efficiency in such pathways can favor greater spontaneous physical activity and, consequently, less body fat deposition. The aim of study was characterizing the nutritional profile and spontaneous physical activity in the condition of Resistance to Obesity (OR). Wistar rats were randomized into standard diet (SD; n = 50) and high-fat diet (HFD; n = 50) groups, after obesity induction, were redistributed into Control (C), False-control (FC), Propensity to obesity (OP) and OR, and then spontaneous physical activity was evaluated. Analyzed parameters: body mass (BM), epididymal (EF), retroperitoneal (RF), visceral (VF) and respective summations (∑), adiposity index (AI), nutritional, morphological, biochemical and metabolic parameters and protein quantification. The comparison of the groups was performed by ANOVA one or two factors, with 5% significance adopted. OP and FC presented high final MC values compared to C and OR. OR had lower EF, RF, VF, ∑ and IA compared to OP. OR had similar values to C and higher HDL than FC and OP. In GTT, OR and C presented similar values and both were lower than OP in the 30 minutes. OP promoted higher values than C for glycemic AUC. OR had higher PPARγ content than C and OP, as well as levels similar to C for leptin and insulin. Spontaneous physical activity did not differ between groups. The results were not enough to show that OR animals have greater lipid oxidative capacity, as well as greater spontaneous physical activity.

Are physical inactivity, sitting time and screen time associated with obstructive sleep apnea in adults? A cross-sectional study.

BACKGROUND: Sitting time, screen time and low physical activity (PA) levels have been associated with several diseases and all-cause mortality. PA is related to better sleep quality and absence of daytime sleepiness, along with lower risks of obstructive syndrome apnea (OSA). However, studies on the relationship between sitting time, screen time and OSA are scarce in the literature. OBJECTIVE: To analyze associations between PA levels, sitting time, screen time and OSA among adults with suspected sleep disorder. DESIGN AND SETTING: Cross-sectional study conducted at Hospital Israelita Albert Einstein. METHODS: Data were collected from 369 adults with suspected sleep disorders who visited the hospital's neurophysiology clinic between August 2015 and January 2017. RESULTS: Correlations between hypopnea and PA indicators were demonstrated for total sitting time (0.123; P = 0.019) and total screen time (0.108; P = 0.038). There was also a correlation between latency for rapid-eye-movement sleep (REM_LAT) and total sitting time (0.103; P = 0.047) and a negative correlation between mean oxyhemoglobin saturation (SaO_Avg) and total PA time (-0.103; P = 0.048). There were no associations between PA parameters and apnea-hypopnea index. After adjusting for confounding factors (body mass index, age and gender), sitting time and screen time were not associated with OSA. CONCLUSION: After adjusting for anthropometric and clinical factors, excessive sitting time or screen time was not associated with OSA in adults suspected of sleep disorders. Age, gender, hypertension, body mass index and waist circumference were associated with OSA.

The Effect of Sodium Bicarbonate Supplementation on Electromyographic Muscle Activity in Healthy, Physically Active Individuals: A Systematic Review.

AIM: The aim of this systematic review was to investigate the effects of sodium bicarbonate supplementation on electromyographic (EMG) muscle activity in healthy, physically active individuals. METHODS: A systematic review of cross-sectional studies, crossover studies and randomized controlled trials was performed to investigate the effects of sodium bicarbonate supplementation on EMG muscle activity in healthy, physically active individuals. Potentially eligible for the systematic review were identified through searches conducted in the PubMed/MEDLINE, Science Direct and Scopus, considering publications from January 1980 to August 2019. The terms used in the search were: sodium bicarbonate, NaHCO3, alkalosis, alkaloses, electromyography, surface electromyography, electromyographies, electromyogram and EMG. Two independent assessors extracted data from the selected articles. Bias analysis was conducted using the Cochrane Risk of Bias tool and methodological quality was appraised using a checklist created based on the guidelines of the Consolidated Standards of Reporting Trials and the International Society of Electrophysiology and Kinesiology. RESULTS: A total of 67 studies were retrieved and seven were included in this review. Only two studies showed significant differences in muscle activity after sodium bicarbonate supplementation. The different EMG signal capturing, processing, and analysis methods used constitute an important limitation to the comparative analyses of the results reported in the studies selected for the present review. CONCLUSION: The results found do not allow us to affirm whether EMG may or may not be a safe tool to assess the effects of sodium bicarbonate supplementation on muscle activity.

Effects of Whole Body Electrostimulation Associated With Body Weight Training on Functional Capacity and Body Composition in Inactive Older People.

Objective: To analyze the effects of whole body electrostimulation (WB-EMS) with body weight training on functional fitness and body composition of older men. Methods: Twenty physically inactive older men were randomized into: Control group (control), performed the body weight exercise training wearing electrostimulation clothing, but without receiving electrical current stimuli (n = 10), and body weight associated with whole body electrostimulation group (BW+WB-EMS), performed the body weight exercise training wearing electrostimulation clothing plus whole body electrostimulation (n = 10). The training sessions were performed twice a week for 6 weeks and included eight exercises using body weight, performed in two sets of eight repetitions. Physical function was assessed using a battery composed of seven tests, six derived from the Senior fitness test and a handgrip strength test. We also measured the muscle thickness (MT) of the biceps and triceps brachii and vastus lateralis. Results: The BW+WB-EMS group presented increased (p < 0.05) performance in the 30-s chair stand test (10.2 ± 3.3 vs. 13.8 ± 5.0 reps), arm curl (16.6 ± 3.9 vs. 19.9 ± 6.1 reps), 6-min walk test (402 ± 96 vs. 500 ± 104 m), and handgrip strength test (30 ± 11 vs. 32 ± 11 kgf). The BW+WB-EMS group also presented increased MT (p < 0.05) in the biceps brachii (17.7 ± 3.0 vs. 21.4 ± 3.4 mm), triceps brachial (14.7 ± 3.6 vs. 17.5 ± 4.1 mm), and vastus lateralis muscles (15.1 ± 2.6 vs. 18.6 ± 4.3 mm). Moderate correlations were found in arm curl (p = 0.011, r = 0.552) but not handgrip strength (p = 0.053, r = 0.439) with changes in the biceps MT. Moderate changes in the 6-min walk distance were significantly correlated with changes in vastus lateralis MT (p = 0.036, r = 0.471). There was a moderate correlation between the changes in the 30-s chair stand test (p = 0.006, r = 0.589) and changes in the vastus lateralis MT. Furthermore, although a moderate correlation (r = 0.438) was found between triceps MT and handgrip strength no significant difference (p = 0.053) was reported. Additionally, there were no statistical differences in any parameters for the control group. Conclusion: WB-EMS with body weight training increased functional fitness and MT in physically inactive older men.