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.

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.

Effects of dynamic and isometric resistance training protocols on metabolic profile in hemodialysis patients: a randomized controlled trial.

The aim of this study was to compare the effect of dynamic (DRT) and isometric (IRT) resistance training on glycemic homeostasis, lipid profile, and nitric oxide (NO) in hemodialysis (HD) patients. Patients were randomly distributed into 3 groups: control (n = 65), DRT (n = 65), and IRT (n = 67). Patients assessed before and after the intervention period were tested for fasting blood glucose, glycated hemoglobin, oral glucose tolerance test, insulin resistance, lipid profile, leptin, insulin, adiponectin, C-reactive protein, and NO . Patients underwent to strength and body composition assessments. Subjects allocated in both DRT and IRT groups took part in a 24-week resistance training program, 3 times per week. Each training session was approximately 1 hour before dialysis and consisted of 3 sets of 8-12 repetitions at low intensity. Total workload was higher in the DRT as compared with the IRT. This heightened workload related to better glycemic homeostasis in HD patients as measured by regulation of insulin, adiponectin, and leptin, while improveing triglycerides, free-fat mass, and muscle strength. Additionally, NO levels were increased in the DRT group. NO was significantly correlated with glucose intolerance (r = -0.42, p = 0.0155) and workload (r = 0.46, p = 0.0022). The IRT group only improved strength (p < 0.05). Twenty-four weeks of DRT improved glycemic homeostasis, lipid profile, and NO in HD patients. Although IRT seems to play an important role in increasing strength, DRT might be a better choice to promote metabolic adjustments in HD patients. Clinical trial: http://www.ensaiosclinicos.gov.br/rg/RBR-3gpg5w. Novelty: DRT might be a better choice for metabolic improvements in patients with chronic kidney disease (CKD). Exercise-training might treat metabolic imbalance in CKD patients.

Effects of pre-dialysis resistance training on sarcopenia, inflammatory profile, and anemia biomarkers in older community-dwelling patients with chronic kidney disease: a randomized controlled trial.

BACKGROUND: Sarcopenia and chronic kidney disease (CKD) have been associated with negative outcomes in older people, including inflammatory profile and anemia biomarkers. AIMS: To investigate the effects of pre-dialysis resistance training (RT) on sarcopenia, inflammatory profile, and anemia biomarkers in older patients with CKD. METHODS: A total of 107 patients with CKD (65.4 ± 3.7 years) were randomly allocated into four groups: sarcopenic RT (n = 37), non-sarcopenic RT (n = 20), sarcopenic control (n = 28), and non-sarcopenic control (n = 22). DXA and handgrip strength were used to classify sarcopenia according to EWGSOP-2. Treatment groups underwent a 24-week intervention with RT before each dialysis session, three times per week. Blood sample analysis for ferritin, hepcidin, iron availability, and inflammatory profile (TNFα, IL-6, and IL-10) was conducted. All-cause mortality was recorded over 5 years. RESULTS: Sarcopenic RT group increased iron availability after the intervention, while their counterparts decreased. Ferritin and hepcidin significantly decreased in sarcopenic RT group. RT elicited a reduction in both TNFα and IL-6, while increasing IL-10 in both intervention groups. The rate of sarcopenic subjects substantially decreased after the intervention period (from 37 to 17 in the RT group; p = 0.01). The proportion of deaths was higher (P = 0.033) for sarcopenic subjects (Controls 35.7% vs RT 29.7%) when compared to non-sarcopenic subjects (Controls 18% vs RT 10%). The proportion of deaths decreased according to the randomization group (X2 = 8.704; P < 0.1). CONCLUSIONS: The 24-week RT intervention elicited a better sarcopenia status, better inflammatory profile, and improved anemia biomarkers. Sarcopenia was associated with higher mortality rate in older patients with CKD.

Low-load resistance training with blood flow restriction prevent renal function decline: The role of the redox balance, angiotensin 1-7 and vasopressin✰,✰✰.

AIMS: We sought to investigate the effect of resistance training (RT) and low-load RT with moderate blood flow restriction (RT+BFR) on blood pressure, exercise pressor response, redox balance and vasoactive peptides, body composition and muscle strength in patients with stage two of chronic kidney disease (CKD). METHODS: We conducted a 6-month randomized controlled exercise intervention in 90 male and female hypertensive CKD patients (58±9 years with estimated glomerular filtration rate (eGFR; of 66.1 ± 1.2 mL/kg/1.73m2). Participants were randomized to one of three groups (n = 30/group); control group (CTL), RT, and RT+BFR. RT and RT+BFR performed three weekly training sessions using similar periodization for six months (two-month mesocycles), but of different intensities. RESULTS: There was similarly effects between RT and RT+BFR in reducing systolic and diastolic blood pressure during daytime and 24hour period (RT: 10.4%; RT+BFR: 10.3% of decrease), fat mass, F2-isoprostanes, asymmetric dimethylarginine (ADMA) and vasopressin (p<0.05 pre-vs post). Also promoted the increase of angiotensin 1-7, nitric oxide (NO), catalase, Trolox equivalent and muscle strength (p<0.05). Both training models attenuated the decline of estimated glomerular filtration rate (p<0.0001 vs CTL). However, only RT+BFR was associated with lower discomfort during exercise (p<0.0001 pre-vs post). Statistical significance was considered with p < 0.05. CONCLUSION: These findings suggest low-load RT+BFR as a promising non-pharmacological strategy to control blood pressure, oxidative stress, vasoactive peptides, and consequently, attenuate the decrease of the eGFR.

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.

Blood Flow Restriction Training Blunts Chronic Kidney Disease Progression in Humans.

PURPOSE: This study aimed to verify the effect of 6 months of periodized resistance training (RT) with and without blood flow restriction (BFR) in patients with stage 2 chronic kidney disease (CKD) on glomerular filtration rate (GFR), uremic parameters, cytokines, and klotho-fibroblast growth factor 23 (FGF23) axis. METHODS: A total of 105 subjects were randomized in three groups of 35 each: control (CTL), RT, and RT + BFR. A first visit was required for an anamnesis to evaluate the number of medications and anthropometric measurements (body weight, height, and body mass index). Muscle strength (one-repetition maximum) was assessed. Venous blood samples were collected at baseline and after 6 months of training in all patients for the analysis of markers of renal function and integrity, as well as for the determination of the inflammatory profile. Statistical significances were adopted with P < 0.05. RESULTS: Both training therapies attenuated the decline of GFR (P < 0.05). The majority of CTL patients declined to stage 3 CKD (88.5%), whereas fewer incidents were noted with RT (25.7%) and RT + BFR (17.1%). Improved uremic parameters as well as inflammation (IL-6, IL-10, IL-15, IL-17a, IL-18, and TNF-α) and klotho-FGF23 axis in RT and RT + BFR (P < 0.05) were observed. Monocyte chemoattractant protein 1 was not changed (P > 0.05) but presented a large effect size (Cohen's d), demonstrating a propensity for improvement. CONCLUSION: Six months of periodized RT with and without BFR in patients with stage 2 CKD attenuated the progression of the disease by maintaining GFR, improving uremic parameters, cytokine profile regulation, and klotho-FGF23 axis.

Resistance training improves sleep quality, redox balance and inflammatory profile in maintenance hemodialysis patients: a randomized controlled trial.

Patients in maintenance hemodialisys (HD) present sleep disorders, increased inflammation, unbalanced redox profiles, and elevated biomarkers representing endothelial dysfunction. Resistance training (RT) has shown to mitigate the loss of muscle mass, strength, improve inflammatory profiles, and endothelial function while decreasing oxidative stress for those in HD. However, the relation between those factors and sleep quality are inadequately described. The aim of this study was to verify the effects of 3 months of RT on sleep quality, redox balance, nitric oxide (NO) bioavailability, inflammation profile, and asymmetric dimethylarginine (ADMA) in patients undergoing HD. Our primary goal was to describe the role of RT on sleep quality. Our secondary goal was to evaluate the effect of RT on NO, metabolism markers, and inflammatory and redox profiles as potential mechanisms to explain RT-induced sleep quality changes. Fifty-five men undergoing maintenance hemodialysis were randomized into either a control (CTL, n = 25) and RT group (RTG; n = 30). Participants in the RT group demonstrated an improvement in sleep pattern, redox, inflammatory profiles, and biomarkers of endothelial function (NO2- and ADMA). This group also increased muscle strength (total workload in RT exercises of upper and lower limbs). These findings support that RT may improve the clinical status of HD patients by improving their sleep quality, oxidative and inflammatory parameters.

Effects of resistance training on hepcidin levels and iron bioavailability in older individuals with end-stage renal disease: A randomized controlled trial.

Anemia is an inherent complication of older individuals with end-stage renal disease (ESRD) that is associated with inflammation which in turn is an important factor in the activation of hepcidin that contributes to the decrease in serum iron. Athough resistance training (RT) seems to reduce inflammation in ESRD, its influence on hepcidin and iron availability in hemodialysis patients is unclear. Therefore, the aim of this study was to exemine the effects of RT in on inflammatory profile, hepcidin, and iron status in older individuals with ESRD. End-stage renal disease patients (N: 157, age: 66.8 ± 3.6; body mass: 73 ± 15 body mass index:27 ± 3), were assigned to control (CTL n: 76) and exercise groups (RT n: 81). RT consisted of 24 weeks/3 days per week of a moderate intensity. There was an increase in the bioavailability of iron (ΔRT: 22.2; ΔCTL: -1 µg/dL, p < 0.0001), a decrease in hepcidin levels (ΔRT: -7.9; ΔCTL: 0.2 ng/mL, p < 0.0001),and an improvement of the inflammatory profile. These novel findings show that RT is a potential coadjuvant to reduce iron deficiency by decreasing the levels of hepcidin and pro-inflammatory markers in older patients undergoing hemodialysis.

Critical velocity estimates running velocity in a 10-km running race in recreational runners / A velocidade crítica estima a velocidade de corrida em uma prova de 10-km em corredores recreacionais

Abstract The aim of this study was to compare the estimated running velocity in a critical velocity (CV) test with the real running velocity in a 10-km race. This is a cross-sectional study with a convenience sample of 34 runners, 20 males and 14 females (42,4 ± 11,0). The participants attended two days of testing and one day to participate in an official 10-km race. During the visits, the following tests were performed: i) 400-meter running track test and ii) 2000 meter running track test. They were randomly selected and held in official athletics track with at least 48 hours rest between them. The athletes were instructed to participate in the study properly recovered, fed and hydrated. The CV was calculated as the linear relation between distance and race time, corresponding to the slope of the linear regression line. Both tests occurred in similar climatic situations. We found good agreement between the velocities estimated through the CV test and the real running velocity of a 10-km race. Although there was a difference in velocities estimated by the CV test and the real 10-km race, the variation delta was low. Thus, these data indicate that the CV test seems to be a good tool for estimating the velocity of a 10-km race. The CV determined in the field with two fixed distances 400 and 2000 meter was valid to estimate the running velocity of a 10-km race.

Resumo Objetivou-se comparar a velocidade de corrida estimada em um teste de velocidade crítica com a velocidade real de corrida em uma corrida de 10 km. Estudo transversal com amostra de conveniência de 34 corredores, sendo 20 do sexo masculino e 14 do feminino (42,4 ± 11,0). Os participantes participaram de dois dias de testes e um dia para participar de uma corrida oficial de 10 km. Durante as visitas, foram realizados os seguintes testes: i) pista de atletismo de 400 metros e ii) pista de corrida de 2000 metros. Eles foram selecionados aleatoriamente e mantidos em pista de atletismo oficial com pelo menos 48 horas de descanso entre eles. Os atletas foram instruídos a participar do estudo devidamente recuperados, alimentados e hidratados. A velocidade crítica (CV) foi calculada como a relação linear entre distância e tempo de corrida, correspondendo à inclinação da linha de regressão linear. Ambos os testes ocorreram em situações climáticas semelhantes. Boa concordância entre as velocidades estimadas através do teste CV e o tempo real de teste de 10 km. Embora tenha havido uma diferença nas velocidades estimadas pelo teste CV e o tempo real de teste de 10 km, o delta de variação foi baixo. Assim, esses dados indicam que o teste CV parece ser uma boa ferramenta para estimar a velocidade de uma corrida de 10 km. O CV determinado no campo com duas distâncias fixas de 400 e 2000 metros foi válido para estimar a velocidade de corrida de 10 km.

Frailty syndrome in older adults from the community and long-term care institutions: an exploratory analysis / Síndrome da fragilidade em idosos da comunidade e de instituições de longa permanência: uma análise exploratória

OBJECTIVES: To investigate the association between Frailty syndrome, lipid profile, anthropometric variables, and the functional capacity of older adults; and to analyze an explanatory model of variables with higher predictive capacity for Frailty syndrome. METHODS: This cross-sectional study included 36 and 86 older adults residing in long-term care facilities and in their households, respectively. Anamnesis was followed by evaluation of anthropometric data, risk of falls, functional tests, and biochemical tests. Frailty syndrome was determined according to the criteria suggested by Fried et al. RESULTS: Geriatric patients classified as frail were older; had higher medication consumption; and presented lower performance in handgrip strength, sit-to-stand, and gait speed tests as compared to pre- and non-frail older adults. CONCLUSION: Gait speed and sit-to-stand tests were significant predictors of Frailty syndrome. Specifically, a good performance in these tests represents a protection factor against Frailty syndrome. Furthermore, gait speed performance was explained by age, handgrip strength performance, and frailty status, while sit-to-stand performance was explained by risk of falls and muscular strength.

OBJETIVOS: Investigar a associação entre síndrome da fragilidade, perfil lipídico, variáveis antropométricas e capacidade funcional de idosos; e analisar um modelo explicativo de variáveis com maior capacidade preditiva para síndrome da fragilidade. MÉTODOS: Este estudo transversal incluiu 36 e 86 idosos residentes em instituições de longa permanência e em suas residências, respectivamente. A anamnese foi seguida pela avaliação dos dados antropométricos, risco de quedas, testes funcionais e testes bioquímicos. A síndrome da fragilidade foi determinada de acordo com os critérios sugeridos por Fried et al. RESULTADOS: Os idosos classificados como frágeis eram mais idosos; tiveram maior consumo de medicação; e apresentaram menor desempenho nos testes de força de preensão palmar, levantar e sentar e velocidade da marcha quando comparados aos idosos pré e não frágeis. CONCLUSÕES: Os testes velocidade da marcha e levantar e sentar foram preditores significativos de síndrome da fragilidade. Especificamente, um bom desempenho nesses testes representa um fator de proteção contra a síndrome da fragilidade. Além disso, o desempenho da velocidade da marcha foi explicado pela idade, desempenho da força de preensão palmar e estado de fragilidade, enquanto o desempenho do levantar e sentar foi explicado pelo risco de quedas e força muscular.