Exercise improves respiratory function, body fluid and nitric oxide in hemodialysis patients.

Emerging evidence suggests that resistance training (RT) can mitigate respiratory muscle weakness in hemodialysis (HD) patients. However, the underlying mechanisms responsible for these beneficial effects remain unclear. The purpose of this study was to assess the impact of periodized RT on respiratory muscle strength and its relationship with handgrip strength (HGS), fat-free mass (FFM), nitric oxide (NO), and interdialytic weight gain (IWG) in HD patients. Thirty-three patients were randomly assigned to two groups: control (CTL; n=18) and RT (n=15). RT group did not perform any additional exercise training specific to the respiratory tract. Maximal inspiratory (MIP) and expiratory (MEP) pressures, peak expiratory flow (PEF), HGS, FFM, NO, and IWG were measured before and after the intervention period. Participants in the RT group engaged in a 24-week RT program, three times per week. RT resulted in significant improvements in MIP, MEP, PEF, as well as enhancements in HGS, FFM, NO, and IWG (p<0.05). Notably, inverse correlations were observed between MIP (r= -0.37, p=0.03) and PEF (r= -0.4, p=0.02) with IWG. Thus, the amelioration of HGS and FFM coincided with a reduction in respiratory muscle weakness among HD patients. Decreased IWG and increased circulating NO are plausible mechanisms contributing to these improvements.

Exercise-Induced Transient Oxidative Stress Is Mitigated in Down Syndrome: Insights About Redox Balance and Muscle Strength.

ABSTRACT: Reis, AL, Deus, LA, Neves, RVP, Corrêa, HL Reis, TL, Aguiar, LS Honorato, FS, Barbosa, JMS, Araújo, TB, Palmeira, TRC, Simões, HG, Prestes, J, Sousa, CV, Ide, BN, and Rosa, TdS. Exercise-induced transient oxidative stress is mitigated in Down syndrome: insights about redox balance and muscle strength. J Strength Cond Res 38(3): e125-e34, 2024-This study aimed to evaluate the acute effects of a session of resistance exercise (RE) performed with elastic tubes on the redox balance and inflammatory profile in individuals with Down syndrome (DS). Subjects ( n = 23) were allocated into 2 groups: individuals with DS (DS; n = 11) and individuals without DS (WDS; n = 12), who performed an acute RE session. Diagnostic assessment included medical history, anthropometric measures (body height, body mass, body mass index, and body composition assessment), biological collections, muscle strength assessments (handgrip and maximal voluntary isometric contraction tests), and exercises. The redox balance and inflammatory profile were assessed in urine and saliva samples before and after an acute RE session. There were no differences between WDS and DS groups for body composition ( p > 0.05). The DS group presented higher values pre and post an acute RE session with elastic tubes for oxidative and proinflammatory markers compared with WDS ( p < 0.05). Uric acid values increased from pre-acute RE session to post-acute RE session for WDS ( p < 0.0001). No differences were identified within groups for the delta analysis ( p > 0.05). Inverse correlations were found between total force and F2-isoprostane, 8OHdG, uric acid, allantoin, IL-6, TNF-α, and the TNF-α:IL-10 ratio. A positive correlation was found between IL-10 and total force. The DS group presented increased peak force in the knee extension and elbow flexion exercises (∼25 and 12%, respectively) but decreases in handgrip strength of ∼7%. The WDS group showed higher peak force values for knee extension, elbow flexion, and handgrip (∼16, 10, and 14%, respectively). The DS group had lower transient elevation of oxidative stress after an acute RE session compared with WDS. Oxidative stress and inflammation responses of DS to an acute RE session with elastic tubes may be insufficient to induce health adaptations for the same relative load compared with WDS.

Modulus of Elasticity of Elastic Tubes Used in Neuromuscular Rehabilitation Programs.

CONTEXT: The elastic tubes have been used for clinical rehabilitation programs in which exercises are performed with submaximal intensities due to the difficulty in the measure the applied force. The authors aimed to quantify the elastic constant of elastic tubes used in neuromuscular rehabilitation programs predicting the force related to elastic tube elongation. A force test was performed by stretching the elastic tubes to determine the relationship between force and elongation. Eight elastic tubes with progressive levels of resistance represented by colors (yellow, red, blue, gray, black, grape, purple, and gold-low to higher resistance) were used. DESIGN: Experimental. METHODS: The test and retest were compared using the paired t test. The agreement and reliability between the test versus retest of pooled means colors were analyzed by plotting the Bland-Altman graph and intraclass correlation coefficient and the coefficient of variation. Pearson correlation was used to verify the validity between measurements. RESULTS: The force values generated from the elastic tube elongation increase according to the color and thickness of elastic tubes with a strong and significant association between them (P < .0001). The elastic constant measurements were similar and presented high intraclass correlation coefficient values, low coefficient of variation values, and were reproducible (P < .0001). CONCLUSIONS: The force could be quantified according to elastic tube length variation by the linear regression equation with reproducibility. It gives greater measurement precision and better training load control when using elastic tubes in strength training programs.

Improving the prognosis of renal patients: The effects of blood flow-restricted resistance training on redox balance and cardiac autonomic function.

NEW FINDINGS: What is the central question of this study? Can resistance training with and without blood flow restriction improve redox balance and positively impact the autonomic cardiac modulation in chronic kidney disease patients? What is the main finding and its importance? Resistance training with and without blood flow restriction improved antioxidant defence (paraoxonase 1), decreased the pro-oxidative myeloperoxidase, improved cardiac autonomic function and slowed the decrease in renal function. We draw attention to the important clinical implications for the management of redox balance and autonomic cardiac function in chronic kidney disease patients. ABSTRACT: Patients with chronic kidney disease (CKD) are prone to cardiovascular diseases secondary to abnormalities in both autonomic cardiac function and redox balance [myeloperoxidase (MPO) to paraoxonase 1 (PON1) ratio]. Although aerobic training improves both autonomic balance and redox balance in patients with CKD, the cardioprotective effects of resistance training (RT), with and without blood flow restriction (BFR), remain unknown. We aimed to compare the effects of RT and RT+BFR on antioxidant defence (PON1), pro-oxidative status (MPO), cardiac autonomic function (quantified by heart rate variability analysis) and renal function. Conservative CKD (stages 1 to 5 who do not need hemodialysis) patients (n = 105, 33 female) of both sexes were randomized into three groups: control (CTL; 57.6 ± 5.2 years; body mass index, 33.23 ± 1.62 kg/m2 ), RT (58.09 ± 6.26 years; body mass index 33.63 ± 2.05 kg/m2 ) and RT+BFR (58.06 ± 6.47 years; body mass index, 33.32 ± 1.87 kg/m2 ). Patients completed 6 months of RT or RT+BFR on three non-consecutive days per week under the supervision of strength and conditioning professionals. Training loads were adjusted every 2 months. Heart rate variability was recorded with a Polar-RS800 and data were analysed for time and frequency domains using Kubios software. The redox balance markers were PON1 and MPO, which were analysed in plasma samples. Renal function was estimated as estimated glomerular filtration rate. The RT and RT+BFR decreased pro-oxidative MPO (RT, ∼34 ng/ml and RT+BFR, ∼27 ng/ml), improved both antioxidant defence (PON1: RT, ∼23 U/L and RT+BFR, ∼31 U/L) and cardiac autonomic function (R-R interval: RT, ∼120.4 ms and RT+BFR, ∼117.7 ms), and slowed the deterioration of renal function (P < 0.0001). Redox balance markers were inversely correlated with heart rate variability time-domain indices. Our data indicated that both training models were effective as non-pharmacological tools to increase the antioxidant defences, decrease oxidative stress and improve the cardiac autonomic function of CKD patients.

Biomarkers and Redox Balance in Aging Rats after Dynamic and Isometric Resistance Training.

Aging muscle is prone to sarcopenia and its associated telomere shortening and increased oxidative stress. Telomeres are protected by a shelterin protein complex, proteins expressed in response to DNA damage. Aerobic exercise training has shown to positively modulate these proteins while aging, but the effects of resistance training are less clear. This investigation was to examine the role of dynamic and isometric RT on markers of senescence and muscle apoptosis: checkpoint kinase 2, 53 kDa protein, shelterin telomere repeat binding 1 and 2, DNA repair, telomere length and redox state in the quadriceps muscle. Fifteen 49-week-old male rats were divided into three groups: control, dynamic resistance training, and isometric resistance training. Dynamic and isometric groups completed five sessions per week during 16 weeks at low to moderate intensity (20-70% maximal load). Only dynamic group decreased expression of 53 kDa protein, proteins from shelterin complex, oxidative stress, and improved antioxidant defense. There was no difference among groups regarding telomere length. In conclusion, dynamic resistance training was more effective than isometric in reducing markers of aging and muscle apoptosis in elderly rats. This modality should be considered as valuable tool do counteract the deleterious effects of aging.

Age-related Decline in Renal Function is Attenuated in Master Athletes.

This study analyzed the kidney function and biomarkers of health in lifelong-trained sprinters and endurance runners, and compared them to untrained aged-matched and young controls. Sixty-two men (21-66 yr.) were recruited and allocated as master athletes from sprints (n=25), master athletes from endurance events (n=8), untrained middle-aged (n=14) and young controls (n=15). Participants underwent anamnesis, anthropometric measures and blood sampling for biochemical analyses of klotho, FGF23 and estimated glomerular filtration rate. Master sprinters presented better kidney function in relation to endurance athletes and their untrained peers (P<0.0001). A number of biochemical variables were observed that negatively (i. e., GDF-15, TGF-Beta, IL-18) or positively (i. e., klotho/FGF23 ratio and sestrin-2) correlated with eGFR. Sestrin-2 presented the strongest association with eGFR (r=0.5, P=0.03). Results also revealed that lifelong-trained individuals presented the highest probability of having better values for cystatin C and thus an estimated glomerular filtration rate that was 37-49% higher than untrained peers. Master sprinters presented better kidney function in relation to endurance athletes and middle-aged untrained peers. Sestrin-2 may play a role in exercise-induced kidney function protection.

Sprint and endurance training in relation to redox balance, inflammatory status and biomarkers of aging in master athletes.

PURPOSE: Studies have shown a positive influence of intense athletic training on several biomarkers of aging, but it remains unclear whether this influence is dependent of exercise-training-mode. This study compared redox balance, cytokine levels and biomarkers of aging between master sprinters and endurance athletes, as well as in young and middle-aged individuals as controls. METHODS: Participants were male master sprinters (SA, 50 ± 8.9yrs; n = 13) and endurance runners (EA, 53 ± 8.2yrs; n = 18) with remarkable athletic experience (~25yrs of practice), besides untrained young (YC, 22.7 ± 3.9yrs; n = 17) and age-matched controls (MC, 45.5 ± 9.8yrs; n = 12). Anamnesis, anthropometrics, biomarkers of aging, inflammation status and oxidative stress parameters were analyzed in all participants. RESULTS: An increased pro-oxidant activity (elevated protein carbonyl; isoprostanes and 8-OHdG) was observed for MC in comparison to remaining groups (p < 0.05). However, SA presented a better antioxidant capacity than both MC and EA, while nitrite/nitrate (NOx) availability was higher for EA and lower for the MC (p < 0.05). Both groups of athletes presented a better anti-inflammatory status than MC (increased IL-10 and lowered IL-6, sIL-6R, sTNF-RI), but worse than YC (increased TNF-α, sTNF-RI, and sIL-6R) (p < 0.05). Telomere length was shorter in MC, which also had lower levels of irisin and klotho, and elevated FGF-23 (p < 0.05). ADMA levels were higher in MC and SA, while irisin was lower in EA when compared to SA and YC (p < 0.05). CONCLUSION: Master athletes presented better redox balance and inflammatory status, with decreased biomarkers of aging compared to control. Regarding exercise mode, a better NO- profile, as a marker of endothelial function, was observed for EA, whereas SA had a better redox balance, cytokines profile and attenuated biomarkers of aging.

Faster and Healthier: Relationship between Telomere and Performance in Master Athletes.

Aging is associated with increased oxidative stress, chronic inflammation, and decreased telomere length (TL). However, the lifestyle of master athletes can lead to a reduced risk of these conditions, and thus attenuates aging and performance deterioration. We aimed to analyze the relationships between TL and relative performance (RP), and their relation to adiposity, oxidative stress, and inflammation in endurance (END) and sprint/power (SPW) master athletes (MAs). Twenty-two world-class MAs visited the laboratory for anamnesis, anthropometrics, and blood sampling. Inflammatory and oxidative stress parameters were assessed using commercial kits. Relative TL was determined in leukocytes through qPCR analyses. A positive association was observed between RP and TL in both groups (SPW: r=0.641; END: r=0.685) and the whole sample (r=0.594). The IL6/IL10 ratio presented an inverse correlation with RP in the whole sample (r=-0.580). Body mass index also demonstrated a negative correlation with TL for the END group (r=-0.690) and the whole sample analysis (r=-0.455). Moreover, the IL6/IL10 ratio was negatively associated with strength/power training hours (r=-0.464), whereas the CAT/TBARS ratio was negatively associated with aerobic training hours (r=-0.482). In conclusion, TL of MAs was associated with RP regardless of the training model (endurance or sprint/power), and inflammation and adiposity were associated with shorter telomeres.

Training Performed Above Lactate Threshold Decreases p53 and Shelterin Expression in Mice.

Telomere shortening is associated to sarcopenia leading to functional impairment during aging. There are mechanisms associated with telomere attrition, as well to its protection and repair. Physical training is a factor that attenuates telomere shortening, but little is known about the effects of different exercise intensities on telomere biology. Thus, we evaluated the effects of exercise intensity (moderate vs. high-intensity domain) on gene expression of senescence markers Checkpoint kinase 2 and tumor suppressor (Chk2 and p53, respectively), shelterin telomere repeat binding 1 and 2 (Trf1/Trf2), DNA repair (Xrcc5), telomerase reverse transcriptase (mTERT) and telomere length in middle aged mice. Three groups were studied: a control group (CTL) and two groups submitted to swimming at intensities below the lactate threshold (LI group) and above the lactate threshold (HI group) for 40 and 20 min respectively, for 12 weeks. After training, the HI group showed reduction in p53 expression in the muscle, and decreased shelterin complex expression when compared to LI group. No differences were observed between groups for mTERT expression and telomere length. Thus, exercise training in high-intensity domain was more effective on reducing markers of senescence and apoptosis. The higher intensity exercise training also diminished shelterin expression, with no differences in telomere length and mTERT expression. Such results possibly indicate a more effective DNA protection for the higher-intensity exercise training.

Longer Telomere Length in Elite Master Sprinters: Relationship to Performance and Body Composition.

Emergent evidence suggests that the long-term healthy lifestyle of master athletes may attenuate aging. We compared telomere length (TL) of high-level master sprinters and non-athlete age-matched controls, and analyzed the relationships of TL with performance and body fat. Elite master sprinters (n=11; aged 50.1±9.2yrs) and healthy untrained controls (n=10; aged 45.4±10.9yrs) had blood samples collected for biochemical and biomolecular analyses. Master sprinters had longer TL, lower body fat and BMI, and a better lipid profile than age-matched controls (p<0.05). A large effect size was verified comparing TL between athletes vs. controls (Cohen's d=1.039), with a significant negative correlation between TL and performance decline per decade (r=-0.624, p<0.01) and a positive correlation of TL and actual performance level (r=0.641, p<0.01). In conclusion, TL of elite master sprinters was longer than their untrained peers, and seems to be not only a marker of health status, but also an indicator of sports longevity since both actual performance level and its decrease over years were related to TL. Further research might assess the TL of elite master endurance athletes for comparison with sprinters, and also investigate the underlying mechanisms by which the attenuation of telomere shortening occurs in master athletes.

Concerns about the application of resistance exercise with blood-flow restriction and thrombosis risk in hemodialysis patients.

BACKGROUND: Hemodialysis (HD) per se is a risk factor for thrombosis. Considering the growing body of evidence on blood-flow restriction (BFR) exercise in HD patients, identification of possible risk factors related to the prothrombotic agent D-dimer is required for the safety and feasibility of this training model. The aim of the present study was to identify risk factors associated with higher D-dimer levels and to determine the acute effect of resistance exercise (RE) with BFR on this molecule. METHODS: Two hundred and six HD patients volunteered for this study (all with a glomerular filtration rate of <15 mL/min/1.73 m2). The RE + BFR session consisted of 50% arterial occlusion pressure during 50 min sessions of HD (intradialytic exercise). RE repetitions included concentric and eccentric lifting phases (each lasting 2 s) and were supervised by a strength and conditioning specialist. RESULTS: Several variables were associated with elevated levels of D-dimer, including higher blood glucose, citrate use, recent cardiovascular events, recent intercurrents, higher inflammatory status, catheter as vascular access, older patients (>70 years old), and HD vintage. Furthermore, RE + BFR significantly increases D-dimer after 4 h. Patients with borderline baseline D-dimer levels (400-490 ng/mL) displayed increased risk of elevating D-dimer over the normal range (≥500 ng/mL). CONCLUSION: These results identified factors associated with a heightened prothrombotic state and may assist in the screening process for HD patients who wish to undergo RE + BFR. D-dimer and/or other fibrinolysis factors should be assessed at baseline and throughout the protocol as a precautionary measure to maximize safety during RE + BFR.

Exploring the impact of short daily haemodialysis on muscle strength and bone health in end-stage kidney disease patients.

BACKGROUND: Short-daily haemodialysis (SDH) has been strongly recommended over conventional haemodialysis (CHD) for end-stage kidney disease patients, though few studies have directly compared the effects of these two haemodialysis (HD) modalities on clinical variables related to patient's health. METHODS: We conducted a cross-sectional study in individuals undergoing HD, comparing epidemiological, clinical, metabolic, inflammatory, anthropometric, bone health/metabolism, and skeletal muscle function according to dialysis modality. One-hundred seventy-eight patients (20.8% females, 62 ± 2.5 years old), were analysed in this study, 86 (48%) of whom were undergoing CHD versus 92 (51%) who were undergoing SDH. RESULTS: SDH patients had significantly higher serum albumin levels (3.93 vs. 3.66 g/dL, P < 0.0001) and higher Kt/v (2.6 vs. 2.38, P < 0.0001). SDH group presented a significantly lower number of erythropoietin-stimulating agents compared with CHD group (percentage: 53.3 vs. 83.7%, P < 0.0001) and had lower levels of serum phosphate (4.9 vs. 5.3 mg/dL, P = 0.004) and parathyroid hormone (PTH) (398.4 vs. 480.4 pg/mL, P < 0.001) compared with CHD patients. In terms of bone health and metabolism, SDH patients had significantly higher total BMD, femur BMD, lumbar BMD, and femoral neck BMD compared with CHD patients (all P < 0.05). SDH patients also had lower anti-osteogenic and inflammatory biomarkers, including FGF23, sclerostin, TNF, IL-18, IL-17a, and C-reactive peptide (all P < 0.05). CHD modality was demonstrated to be a risk factor for low BMD (odds ratio: 4.02; 95% CI: 1.59-10.2, P = 0.003). In terms of skeletal muscle function, SDH patients had significantly higher 6-minute walking test (444.6 vs. 424.9 m, P = 0.04) and higher fat-free mass (52.3 vs. 51.68 kg, P = 0.02) compared with CHD patients. Higher fat-free mass and handgrip strength were associated with a 34% and 23% lower risk of low BMD, respectively. SDH patients had lower levels of the uremic toxin asymmetric dimethyl-l-arginine (ADMA) (1.8 vs. 2.07 µM, P = 0.002) and fasting blood glucose (132.6 vs. 141.7 mg/dL, P < 0.02) than CHD group. SDH patients also displayed higher levels of haemoglobin when compared with CHD group (11.9 vs. 10.2 g/dL, P < 0.0001). CONCLUSIONS: The present study improves our understanding of the relationship between dialysis modality and clinical variables that may influence HD patient's health. Grip strength and lean mass were positively correlated with bone mineral density in HD patients regardless of dialysis modality. SDH was associated with better bone mineral density, inflammatory profile, and skeletal muscle function when compared with CHD patients. These findings provide more evidence of the clinical benefits of SDH that should be explored in greater detail.

Intensity of Depression Symptoms Is Negatively Associated with Catalase Activity in Master Athletes.

BACKGROUND: This study examined associations between scores of depression (DEPs), thiobarbituric acid-reactive substances (TBARS), superoxide dismutase (SOD), and catalase activity (CAT) in master athletes and untrained controls. METHODS: Participants were master sprinters (MS, n = 24; 50.31 ± 6.34 year), endurance runners (ER, n = 11; 51.35 ± 9.12 year), untrained middle-aged (CO, n = 13; 47.21 ± 8.61 year), and young untrained (YU, n = 15; 23.70 ± 4.02 year). CAT, SOD, and TBARS were measured in plasma using commercial kits. DEPs were measured by the Beck Depression Inventory-II. An ANOVA, Kruskal-Wallis, Pearson's, and Spearman's correlations were applied, with a significance level of p ≤ 0.05. RESULTS: The CATs of MS and YU [760.4 U·µL 1 ± 170.1 U·µL 1 and 729.9 U·µL 1 ± 186.9 U·µL 1] were higher than CO and ER. The SOD levels in the YU and ER [84.20 U·mL-1 ± 8.52 U·mL-1 and 78.24 U·mL-1 ± 6.59 U·mL-1 (p < 0.0001)] were higher than CO and MS. The TBARS in CO [11.97 nmol·L-1 ± 2.35 nmol·L-1 (p < 0.0001)] was higher than in YU, MS and ER. MS had lower DEPs compared to the YU [3.60 ± 3.66 vs. 12.27 ± 9.27 (p = 0.0002)]. A negative correlation was found between CAT and DEPs for master athletes [r = -0.3921 (p = 0.0240)] and a weak correlation [r = -0.3694 (p = 0.0344)] was found between DEPs and the CAT/TBARS ratio. CONCLUSIONS: In conclusion, the training model of master sprinters may be an effective strategy for increasing CAT and reducing DEPs.

Could sarcopenia-related mortality in end-stage renal disease be underpinned by the number of hospitalizations and cardiovascular diseases?

PURPOSE: To investigate the association between sarcopenia with the number of all-cause mortality, hospitalizations, and cardiovascular diseases in patients with end-stage renal disease (ESRD). METHODS: 247 patients with ESRD (women, n = 97) (66.6 ± 3.53 years) participated in this study. At baseline, all participants were measured with dual-energy X-ray absorptiometry and handgrip dynamometer and were prospectively followed up for 5 years. The European Working Group on Sarcopenia in Older People guidelines were utilized for Sarcopenia determination. Cox proportional hazard analysis adjusted for established risk factors was used to quantify the risk between Sarcopenia and all-cause mortality. RESULTS: Sixty-five participants (26%) were determined to have Sarcopenia at baseline and 38 (15%) have died during the follow-up. At baseline, Participants with Sarcopenia had lower body mass index and fat-free mass index. Moreover, through the 5-year follow-up, sarcopenic patients had higher number of cardiovascular disease (56.9% vs. 12.6%) and hospitalizations (93.8% vs. 49.5%) (all P < 0.0001). Sarcopenia was associated with significantly higher risk of mortality, [Hazard ratio = 3.3, (95% CI: 1.6-6.9), P = 0.001]. CONCLUSION: Sarcopenia may be a risk factor for hospitalizations, cardiovascular diseases, and all-cause mortality in patients with ESRD. These results provide support of the relevance in assessing sarcopenia in the clinical practice of chronic kidney disease and how muscle mass and strength may negatively impact the daily life of ESRD patients undergoing hemodialysis. Greater efforts at preventing muscle wasting and malfunctioning are needed through the worldwide healthcare system.

Higher sirt1 is associated with a better body composition in master sprinters and untrained peers.

Sirt1 is an enzyme involved in several anti-aging pathways. Associations between Sirt1, age, and body fat (BF) were assessed in master sprinters (MS; n = 35; 50.25 ±5.93 yr.), untrained young non-athletes (UY; n = 32; 23.78 ±3.98 yr.), and untrained middle-aged (UMA; n = 24; 47.29 ±8.04 yr.). BF was assessed using a skinfold protocol, and Sirt1 was measured in plasma by using commercial kits. Sirt1 of MS (17.18 ±4.77 ng/mL) was higher than UMA (6.36 ±2.29 ng/mL; p<0.0001) and did not differ from UY (20.26 ±6.20 ng/mL). Relative BF of MS was lower than UMA (12.71 ±4.07% vs. 22.13 ±4.18%; p<0.0001). Sirt1 was negatively correlated with chronological age (r = -0.735; p<0.0001) when combining UY and UMA in the analysis. However, when Sirt1 of MS and UY was analyzed together, no significant relationship between Sirt1 and chronological age was observed (r = -0.243; p = 0.083). Sirt1 correlated inversely with BF (r = -0.743; p<0.0001) for UY and UMA. Stepwise multiple regression revealed that being either a young or master athlete and body adiposity are possible predictors of Sirt1 levels. MS and UY were associated with higher levels of Sirt1, while UMA and increased BF were associated with lower levels of this enzyme. The relationships among Sirt1, BF, and chronological age of young and middle-aged non-athletes were not statistically significant when the middle-aged participants were MS. These findings suggest possible links between Sirt1 and body composition, which may play roles in the rate of biological aging.HighlightsLower levels of Sirt1 are associated with higher body fat.Master athlete lifestyle seems to promote higher Sirt1 Levels.

Impact of cluster set resistance training on strength, functional capacity, metabolic and inflammatory state in older hemodialysis subjects: A randomized controlled clinical trial.

BACKGROUND AND AIMS: Hemodialysis-associated neuromuscular dysfunction appears to be counteracted by resistance training (RT) in older patients with chronic kidney disease (CKD). Thus, the aim of the present study was to evaluate the impact of cluster-set RT protocol on anthropometric parameters, functional capacities, and biochemical variables in older patients with CKD. METHODS AND RESULTS: Seventy-eight older patients (age: 57.55 ± 4.06 years) with CKD undergoing maintenance hemodialysis participated, and were randomly divided into control group (CG, N = 26), traditional RT (RT, N = 26) and cluster-set RT (RT-CS, N = 26) groups. Participants completed 24 weeks of RT three times per week, 1 h and 30 min before the hemodialysis session. Patients from the RT-CS group displayed increased adherence as compared to the RT group (66.35 % versus 61.73 %, p < 0.0001). There was an improvement of all anthropometric variables, handgrip strength, timed up and-go (TUG) and six-minute walking test (6MWT) following both training protocols when compared to control group and pre-intervention values. Fasting blood glucose decreased for both RT and RT-CS groups as compared with pre-intervention, without differences between training protocols and CG. Glycated hemoglobin, inflammatory cytokines, and triglycerides decreased in RT and RT-CS groups as compared with pre-intervention and CG, without differences between them. Furthermore, the RT-CS protocol resulted in a greater number of people who were responsive to training when compared to traditional training. CONCLUSIONS: RT-CS is a clinically valuable tool to improve anthropometric parameters, handgrip strength, TUG, 6MWT, fasting blood glucose, and cytokines in CKD older patients.

A systematic review and meta-analysis demonstrating Klotho as an emerging exerkine.

Klotho is an anti-aging protein with several therapeutic roles in the pathophysiology of different organs, such as the skeletal muscle and kidneys. Available evidence suggests that exercise increases Klotho levels, regardless of the condition or intervention, shedding some light on this anti-aging protein as an emergent and promising exerkine. Development of a systematic review and meta-analysis in order to verify the role of different exercise training protocols on the levels of circulating soluble Klotho (S-Klotho) protein. A systematic search of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE through PubMed, EMBASE, CINAHL, CT.gov, and PEDro. Randomized and quasi-randomized controlled trials that investigated effects of exercise training on S-Klotho levels. We included 12 reports in the analysis, comprising 621 participants with age ranging from 30 to 65 years old. Klotho concentration increased significantly after chronic exercise training (minimum of 12 weeks) (Hedge' g [95%CI] 1.3 [0.69-1.90]; P < 0.0001). Moreover, exercise training increases S-Klotho values regardless of the health condition of the individual or the exercise intervention, with the exception of combined aerobic + resistance training. Furthermore, protocol duration and volume seem to influence S-Klotho concentration, since the effect of the meta-analysis changes when subgrouping these variables. Altogether, circulating S-Klotho protein is altered after chronic exercise training and it might be considered an exerkine. However, this effect may be influenced by different training configurations, including protocol duration, volume, and intensity.

Could cardiac autonomic modulation be an objective method to identify hypobaric hypoxia symptoms at 25.000ft among Brazilian military airmen?

Hypobaric hypoxia during a flight can cause accidents, resulting in deaths. Heart rate variability may be more sensitive than self-reported hypoxia symptoms to the effects of HH. The level of physical fitness can contribute to efficient cardiac autonomic modulation. However, no studies have examined the association between fitness, heart rate variability, and the time of onset of hypobaric hypoxia symptoms. To analyze the influence of hypobaric hypoxia on cardiac autonomic function at the time of onset of the first symptoms and its association with physical fitness. Male airmen trained and belonging to the staff of the Brazilian Air Force (n = 23; 30 ± 6.7 years) participated in a flight simulation in a 25.000 ft hypobaric chamber. Heart rate variability was recorded with a Polar® cardiac monitor. Data were analyzed in the time-domain method using Kubios software. We evaluated pulse oximetry with the Mindray PM-60 oximeter. Physical fitness assessment test results were collected from the archive. At moments rest vs. hypoxia revealed a decrease in heart rate variability indices iRR and RMSSD (p < 0.001). The individual analysis of hypoxia-rest variation showed that 100% of the airmen had a negative delta for both iRR and RMSSD indices. The time of onset of hypoxia symptoms was not associated with body composition, physical fitness, oxygen saturation, and HRV indices. Also, we suggest that cardiac autonomic modulation seems to be more sensitive to the effects of hypobaric hypoxia at 25.000 ft than the self-reported subjective perception of symptoms. Further devices that alert to a hypoxic condition during a flight should consider heart rate variability allowing more time and security to reestablish control of the flight.

MicroRNA levels in hemodialysis patients following resistance training: Associations with functional performance, inflammatory profile, sestrins-2, and nitric oxide.

OBJECTIVE: Investigate the effects of long-term resistance training (RT) on expression of the four selected microRNAs (miRNA or mir) and further association with biomarkers related to functional performance in older end-stage renal disease (ESRD) patients undergoing hemodialysis. METHODS: Twenty-five older hemodialysis patients (glomerular filtration rate <15 mL/min/1.73 m2 aged 68.28 ± 1.06) were recruited for the study. Patients were allocated to two groups (control, n = 12 and RT, n = 13). The RT group completed 24 weeks of training, with sessions held three times per week on alternate days. Blood samples were collected pre- and post- intervention for miRNA and biochemical assays. Results were considered significant at P < 0.05. RESULTS: RT promoted benefits in inflammatory profile, nitric oxide, sestrins-2, anthropometric data, and functional performance. Trained subjects presented a 51% decrease in miRNA-31 after intervention. In addition, miRNA-1 increased 128% after RT protocol. miRNA-1 significantly correlated with functional performance, inflammatory profile, sestrins-2, and nitric oxide (all P < 0.05). CONCLUSIONS: These results suggest that the upregulation of miRNA-1 could be associated with physiological benefits promoted by RT in hemodialysis patients, providing novel understanding for potential regulatory miRNA effects on physiological RT response. These findings might point out to strategic direction for future studies.

Metabolic and hormonal responses to chronic blood-flow restricted resistance training in chronic kidney disease: a randomized trial.

Maintenance of glycemic and lipemic homeostasis can limit the progression of diabetic kidney disease. Resistance training (RT) is effective in controlling glycemia and lipemia in kidney disease; however, the effect of RT with blood flow restriction (RT+BFR) on these metabolic factors has not been investigated. We aimed to verify if chronic (6 months) RT and RT+BFR performed by patients with stage-2 chronic kidney disease (CKD) improves their glycemic homeostasis and immunometabolic profiles. Patients with CKD under conservative treatment (n = 105 (33 females)) from both sexes were randomized into control (n = 35 (11 females); age 57.6 ± 5.2 years), RT (n = 35 (12 females); age 58.0 ± 6.2 years), and RT+BFR (n = 35 (10 females); 58.0 ± 6.4 years) groups. Chronic RT or RT+BFR (6 months) was performed 3 times per week on non-consecutive days with training loading adjusted every 2 months, RT 50%-60%-70% of 1RM, and RT+BFR 30%-40%+50% of 1RM and fixed repetition number. Renal function was estimated with the glomerular filtration rate and serum albumin level. Metabolic, hormonal, and inflammatory assessments were analyzed from blood samples. Six months of RT and RT+BFR were similarly effective in improving glucose homeostasis and hormone mediators of glucose uptake (e.g., irisin, adiponectin, and sirtuin-1), decreasing pro-inflammatory and fibrotic proteins, and attenuating the progression of estimated glomerular filtration rate. Thus, RT+BFR can be considered an additional exercise modality to be included in the treatment of patients with stage 2 chronic kidney disease. Trial registration number: U1111-1237-8231. URL: http://www.ensaiosclinicos.gov.br/rg/RBR-3gpg5w/, no. RBR-3gpg5w. Novelty: Glycemic regulation induced by resistance training prevents the progression of CKD. Chronic RT and RT+BFR promote similar changes in glycemic regulation. RT and RT+BFR can be considered as non-pharmacological tools for the treatment of CKD.