Effects of physical training on functional, clinical, morphological, behavioural and psychosocial outcomes in post-COVID-19 infection: COVID-19 and REhabilitation study (CORE-study)-a study protocol for a randomised controlled clinical trial.

BACKGROUND: The COVID-19 pandemic remains ongoing, with a significant number of survivors who have experienced moderate to severe clinical conditions and who have suffered losses of great magnitude, especially in functional capacity, triggering limitations to daily autonomy and quality of life. Among the possibilities of intervention for disease rehabilitation, physical exercise training stands out, which can benefit several health outcomes and favours the adoption of healthier behaviours. Therefore, the aim of the study will be to analyse the effects of physical training on the functional, clinical, morphological, behavioural and psychosocial status in adults and the elderly following COVID-19 infection. METHODS: A randomised controlled clinical trial is to be conducted in parallel, with the experimental group undergoing an intervention involving a multicomponent physical rehabilitation programme, carried out at the Sports Center in partnership with the Academic Hospital of the Federal University of Santa Catarina, in Florianópolis, Brazil. Participants will be adults and the elderly, of both sexes, in a post-COVID-19-infection state, who were hospitalised during the infection. The intervention will have a total duration of 24 weeks and will include a multicomponent physical training programme, which will have gradual progression in frequency, duration and intensity over time. Regarding the outcomes, before, at the 12th and after 24 weeks of intervention, functional (primary outcome = functional index of aerobic capacity), clinical, morphological, behavioural and psychosocial outcomes will be assessed. DISCUSSION: This study will contribute to a greater understanding of the safety, adherence and benefits of physical training in the rehabilitation of post-COVID-19 patients. The results of this study will be disseminated through presentations at congresses, workshops, peer-reviewed publications and local and international conferences, especially with a view to proposing a post-COVID-19 rehabilitation care protocol. TRIAL REGISTRATION: ReBEC, RBR-10y6jhrs . Registered on 22 February 2022. 2015.

The antinociceptive effect of manual acupuncture in the auricular branch of the vagus nerve in visceral and somatic acute pain models and its laterality dependence.

AIMS: The vagus nerve provides an important route to the central nervous system, and its brain projections are involved in nociceptive control and pain perception. We investigated the effect of ABVN stimulation on the inhibition of nociceptive signaling and the role of the cholinergic system in its neurobiological effects in models of visceral-somatic pain in rats, as well as the potential difference in stimulus laterality. MATERIALS AND METHODS: Male and female Wistar rats were pretreated with auricular acupuncture in the ABVN and submitted to the visceral-somatic nociception model by acetic acid or somatic nociception by formalin. Vagotomy and pharmacological tools were used to verify the participation of the cholinergic system in the experiments. KEY FINDINGS: Acupuncture on the left, but not the right, in the ABVN inhibited nociceptive signaling in the visceral-somatic nociception model in male and female rats. Acupuncture on the left ABVN reduced the response time in the formalin test. The cervical vagotomy of the left branch, but not the right, also inhibited nociceptive signaling in the visceral-somatic nociception model and reduced the effect of ABVN stimulation. Furthermore, cholinergic antagonists reduced the left ABVN stimulation effects in the same model. SIGNIFICANCE: Our data show that only the stimulation in the left ABVN is capable of producing antinociceptive effect in acute pain models in rats, and that it is dependent on the activation of the vagus nerve caudal to the nodose ganglion, as well as the muscarinic and nicotinic cholinergic receptors.

Relative fat mass is a better tool to diagnose high adiposity when compared to body mass index in young male adults: A cross-section study.

BACKGROUND AND AIM: Relative fat mass (RFM) is a new method to estimate whole-body fat percentage in adults using an anthropometric linear equation. We aimed to assess the association between RFM and body fat (BF), evaluated by dual x-ray absorptiometry (DXA) or bioelectrical impedance (BIA), in young male adults. METHODS: Eighty-one young males were assessed for BF fat and free fat mass (by BIA and DXA), waist circumference. BMI and RFM were then calculated from data collected from the subjects. The agreement between BMI and RFM or BIA/DXA was assessed by Pearson's Correlation and Kappa index. Univariate and multivariate linear regression were applied. RESULTS: Analyzing all the participants together, the correlation between RFM and DXA (rDXA = 0.90) or RFM and BIA (rBIA = 0.88) were slightly higher than the correlation between BMI and DXA (rDXA = 0.79) or BMI and BIA (rBIA: 0.82). When analyzed by BF, low BF (LBF) individuals showed a much higher correlation with RFM (rDXA = 0.58; rBIA = 0.73) than BMI (rDXA = 0.24; rBIA: 0.46). However, subjects with excess BF (EBF) presented similar correlations when comparing RFM (rDXA = 0.80; rBIA = 0.64) and BMI (rDXA = 0.78; rBIA = 0.64). In general, RFM presented a higher strength of agreement with DXA and BIA (kDXA = 0.75; kBIA = 0.67) than BMI (kDXA = 0.63; kBIA = 0.60). Multivariable linear regression also revealed high associations between RFM and DXA or RFM and BIA (r2DXA = 0.85; r2BIA = 0.81). CONCLUSION: Our findings suggest that RFM shows a good correlation and association with BF measured by DXA and BIA in young male adults. Furthermore, RFM seems to be better correlated to BF in LBF individuals when compared to BMI. Therefore, further studies investigating RFM as a tool to assess BF and obesity are motivated.

Impact of different fructose concentrations on metabolic and behavioral parameters of male and female mice.

Clinical evidence has shown that a high consumption of sugar-sweetened beverages is a risk factor for developing obesity and metabolic syndrome. There has also been increasing interest in the potential effects of high-fructose intake on behavior. The present study evaluated sex differences in behavioral and metabolic characteristics in response to chronic fructose intake in mice. Swiss mice (3-months-old) had access to tap water or fructose-water solution (at 15% or 30% w/v) ad libitum for nine weeks. After the 8 weeks, the mice were submitted to a battery of behavioral tests. A glucose tolerance test was performed one day after these behavioral tests, and the next day blood was collected for biochemical analysis. At a 15% concentration, fructose-intaking resulted in higher plasma cholesterol levels and glucose intolerance in mice that paralleled with a passive stress-coping behavior in the female mice and lower self-care behavior in the male and the female mice. At a 30% concentration, fructose-intaking resulted in higher body mass gain and higher plasma cholesterol and triglycerides levels in the male and the female mice, whereas glucose intolerance was more pronounced in the male mice. Spatial memory impairments and lower self-care behavior were observed in the male and the female mice, while passive stress-coping behavior was observed only in the female mice. Collectively, high-fructose intake induces metabolic and behavioral alterations in mice, with the males being more susceptible to glucose metabolism dysfunctions and the females to depressive-like endophenotypes.

Short- and long-term effects of maternal dyslipidaemia on blood pressure and baroreflex sensitivity in male rat offspring.

Maternal dyslipidaemia is a predisposing factor for arterial hypertension in male rat offspring at adulthood. This study was designed to investigate the short- and long-term effects of maternal dyslipidaemia on blood pressure (BP) and baroreflex control in male rat offspring. Animals were obtained from mothers who received a dyslipidaemic (DLP, n = 7) or control (CTL, n = 7) diet during pregnancy and lactation. At 30 and 90 days of age, arterial pressure (AP), heart rate (HR) and baroreflex function were evaluated. In addition, spectral analysis of the systolic AP, diastolic AP, mean AP, HR, and spontaneous baroreflex were assessed. Data were expressed as mean ± SEM and Student's t-test was used for comparison among groups, with statistical significance considered to be P < .05. At 30 days of age, male offspring had similar BP, HR and preserved baroreflex sensitivity. In addition, low frequency (LF) oscillation, high frequency (HF) oscillation and LF/HF ratio of AP and HR were similar in juvenile rats. At 90 days of age, male offspring from dyslipidaemic dams had augmented BP (P < .05) when compared to CTL group. Adult male rats from dyslipidaemic dams had a reduction in baroreflex control (P < .05) in comparison to CTL rats. The present study indicates that offspring from dams fed on a dyslipidaemic diet during pregnancy and lactation do not show alteration in blood pressure and baroreflex control in early life, but display a decline in baroreflex control and hypertension in adulthood.

Acute effects of Resistance exercise performed on ladder on energy metabolism, stress, and muscle damage in rats

Abstract AIMS To evaluate the acute effects of a resistance exercise session performed on ladder on energy metabolism, stress, and muscle damage in rats. METHODS Male Wistar rats were randomly distributed in Exercise (E) (n=30) and Control (C) (n = 20) groups. The E group performed a resistance exercise session on a vertical ladder with weights on their tails. Blood samples were collected at rest and after each climb to analyze lactate levels and ten minutes after the last climb to analyze lactate dehydrogenase (LDH), creatine kinase (CK), and corticosterone levels. RESULTS Blood lactate levels remained stable during exercise. Serum corticosterone, blood glucose, LDH and CK levels increased and glycogen content decreased in the E group, when compared to the C group. CONCLUSION These results suggest that resistance exercise performed on ladder is a model of high-intensity exercise. However, the stabilization of lactate during the session suggests that the aerobic metabolism is an important factor during the intervals between climbs.(AU)

Increased expression of angiotensin II type 2 receptors in the solitary-vagal complex blunts renovascular hypertension.

Angiotensin II increases and decreases arterial pressure by acting at angiotensin type 1 and type 2 receptors, respectively. Renovascular hypertensive rats exhibit a high level of activity of the peripheral and central renin-angiotensin system. Therefore, in the present study, we evaluated the effect of increasing the expression of angiotensin type 2 receptors in the solitary-vagal complex (nucleus of the solitary tract/dorsal motor nucleus of the vagus), a key brain stem region for cardiovascular regulation, on the development of renovascular hypertension. Holtzman normotensive rats were implanted with a silver clip around the left renal artery to induce 2-kidney 1-clip renovascular hypertension. Three weeks later, rats were microinjected in the solitary-vagal complex with either an adenoassociated virus to increase the expression of angiotensin type 2 receptors or with a control vector. We observed that increasing angiotensin type 2 receptor expression in the solitary-vagal complex attenuated the development of renovascular hypertension and also reversed the impairment of the baroreflex and the increase in the low-frequency component of systolic blood pressure observed in renovascular hypertensive rats. Furthermore, an observed decrease in mRNA levels of angiotensin-converting enzyme 2 in the solitary-vagal complex of renovascular hypertensive rats was restored to control levels after viral-mediated increases in angiotensin type 2 receptors at this site. Collectively, these data demonstrate specific and beneficial effects of angiotensin type 2 receptors via the brain of hypertensive rats and suggest that central angiotensin type 2 receptors may be a potential target for therapeutics in renovascular hypertension.

Influence of upper-body exercise order on hormonal responses in trained men.

The aim of this study was to examine acute hormonal responses after different sequences of an upper-body resistance-exercise session. Twenty men completed 2 sessions (3 sets; 70% 1-repetition maximum; 2 min passive rest between sets) of the same exercises in opposite sequences (larger to smaller vs. smaller to larger muscle-group exercises). Total testosterone (TT), free testosterone (FT), testosterone/cortisol (T/C) ratio, sex-hormone-binding globulin (SHBG), growth hormone (GH), and cortisol (C) concentrations were measured before and immediately after each sequence. The results indicate that the GH concentration increased after both sessions, but the increase was significantly greater (p < 0.05) after the sequence in which larger muscle-group exercises were performed prior to the smaller muscle-group exercises. No differences were observed between sessions for TT, FT, SHBG, C, or the T/C ratio at baseline or immediately after resistance exercise. These results indicate that performing larger muscle-group exercises first in an upper-body resistance-exercise session leads to a significantly greater GH response. This may have been due to the significantly greater exercise volume accomplished. In summary, the findings of this investigation support the common prescriptive recommendation to perform larger-muscle group exercises first during a resistance-exercise session.

The effects of exercise modalities on adiposity in obese rats

OBJECTIVE: The aim of the present study was to evaluate the effect of both swimming and resistance training on tumor necrosis factor-alpha and interleukin-10 expression, adipocyte area and lipid profiles in rats fed a high-fat diet. METHODS: The study was conducted over an eight-week period on Wistar adult rats, who were divided into six groups as follows (n = 10 per group): sedentary chow diet, sedentary high-fat diet, swimming plus chow diet, swimming plus high-fat diet, resistance training plus chow diet, and resistance training plus high-fat diet. Rats in the resistance training groups climbed a vertical ladder with weights on their tails once every three days. The swimming groups swam for 60 minutes/day, five days/week. RESULTS: The high-fat diet groups had higher body weights, a greater amount of adipose tissue, and higher tumor necrosis factor-alpha expression in the visceral adipose tissue. Furthermore, the high-fat diet promoted a negative change in the lipid profile. In the resistance training high-fat group, the tumor necrosis factor-alpha expression was lower than that in the swimming high-fat and sedentary high-fat groups. Moreover, smaller visceral and retroperitoneal adipocyte areas were found in the resistance training high-fat group than in the sedentary high-fat group. In the swimming high-fat group, the tumor necrosis factor-alpha expression was lower and the epididymal and retroperitoneal adipocyte areas were smaller compared with the sedentary high-fat group. CONCLUSION: The results showed that both exercise modalities improved the lipid profile, adiposity and obesity-associated inflammation in rats, suggesting their use as an alternative to control the deleterious effects of a high-fat diet in humans.

The effects of exercise modalities on adiposity in obese rats.

OBJECTIVE: The aim of the present study was to evaluate the effect of both swimming and resistance training on tumor necrosis factor-alpha and interleukin-10 expression, adipocyte area and lipid profiles in rats fed a high-fat diet. METHODS: The study was conducted over an eight-week period on Wistar adult rats, who were divided into six groups as follows (n = 10 per group): sedentary chow diet, sedentary high-fat diet, swimming plus chow diet, swimming plus high-fat diet, resistance training plus chow diet, and resistance training plus high-fat diet. Rats in the resistance training groups climbed a vertical ladder with weights on their tails once every three days. The swimming groups swam for 60 minutes/day, five days/week. RESULTS: The high-fat diet groups had higher body weights, a greater amount of adipose tissue, and higher tumor necrosis factor-alpha expression in the visceral adipose tissue. Furthermore, the high-fat diet promoted a negative change in the lipid profile. In the resistance training high-fat group, the tumor necrosis factor-alpha expression was lower than that in the swimming high-fat and sedentary high-fat groups. Moreover, smaller visceral and retroperitoneal adipocyte areas were found in the resistance training high-fat group than in the sedentary high-fat group. In the swimming high-fat group, the tumor necrosis factor-alpha expression was lower and the epididymal and retroperitoneal adipocyte areas were smaller compared with the sedentary high-fat group. CONCLUSION: The results showed that both exercise modalities improved the lipid profile, adiposity and obesity-associated inflammation in rats, suggesting their use as an alternative to control the deleterious effects of a high-fat diet in humans.