A Comparative Analysis of Acute Physiological and Perceptual Responses in Whole-Body and Ergometer-Based High-Intensity Interval Training Protocols.

The primary aim of the present investigation was to compare the acute physiological and perceptual responses between two modes of interval training using a randomized crossover design. More specifically, eleven young adult participants (23 ± 4 years, 77 ± 13 kg, 178 ± 7 cm) performed two protocols: one composed of whole-body calisthenics exercises and another on a cycle ergometer. Both protocols encompassed eight 20 s bouts at intensities equivalent to all-out (HIIT-WB) and 170% of the maximal power output (HIIT-C), respectively, interspersed with 10 s of passive rest. The peak and average heart rate, the rating of perceived effort, and blood lactate, creatine kinase, and lactate dehydrogenase concentrations were measured. Aside from blood lactate (HIIT-WB = 9.4 ± 1.8 mmo/L; HIIT-C = 12.5 ± 2.5 mmol/L, p < 0.05) and the rating of perceived exertion (HIIT-WB = 8.8 ± 0.9; HIIT-C = 9.6 ± 0.5, p < 0.05), physiological responses did not significantly differ between protocols (all p > 0.05), with high average heart rate values (HIIT-WB = 86 ± 6% HRmax; HIIT-C = 87 ± 4% HRmax) and a low magnitude of muscle damage, as inferred by CK and LDH concentrations (HIIT-WB = 205.9 ± 56.3 and 203.5 ± 72.4 U/L; HIIT-C = 234.5 ± 77.1 and 155.1 ± 65.3 U/L), respectively. It can be concluded that both protocols elicit vigorous heart rate responses and a low magnitude of muscle damage and, therefore, appear as viable alternatives to improve aerobic fitness. The inclusion of a whole-body HIIT protocol may be an interesting alternative for training prescription in relation to more common interval training protocols.

COVID-19 is more lethal in hemodialysis chronic kidney disease patients with low physical capacity.

INTRODUCTION: The mortality rate in patients on maintenance hemodialysis (HD) is high and is associated with low functional capacity (FC). We analyzed the association of FC and COVID-19 lethality among HD patients. METHODS: A cohort study that included evaluations of FC in patients on HD was underway, and the association between FC and lethality was included as an ad-hoc outcome. RESULTS: One hundred and twelve patients were submitted to a physical, 31 patients contracted symptomatic COVID-19, 20 recovered and 11 died (lethality rate of 35.5%). There was a difference between survivors and non-survivors on six-minutes-walking-test (6MWT) 386.1 ± 112.8 versus 296.9 ± 103.3 meters (p = 0.04), 30 s sit-to-stand test (30CST) score 11.7 ± 3.1 versus 7.7 ± 4.1 (p = 0.006), and timed up and go test (TUG) 9.4 versus 13.6 s (p = 0.009). There was also an association between percentages of predicted 6MWT, 30CST, and TUG with COVID-19 lethality. CONCLUSION: Patients on maintenance HD with poorer physical performance presented the worst prognosis from COVID-19 pandemic.

Effects of intradialytic exercise on functional capacity in patients with end-stage chronic kidney disease: a systematic review and meta-analysis.

The study aimed to investigate the effect of intradialytic exercise training programmes on the submaximal functional capacity of patients with kidney failure. We searched for randomized clinical trials that assessed submaximal functional capacity using the 6-min walk test (6 MWT) in adult patients on maintenance haemodialysis submitted to intradialytic physical training. The search was performed on 15 October 2021, in different databases. Random-effect, multivariate meta-regression adjusted for multiplicity were performed to examine the relationship between exercise effect and covariates. Intradialytic physical exercise induced greater changes in 6MWT distance (k = 18; n = 1,458; WMD: 37.0; 95% CI 29.3; 50.6 metres) than control groups, with substantial heterogeneity (I2 = 78.3%). Aerobic, strength, and combined exercise promoted an average increase of 48.7 (95%CI 30.9; 66.4 metres), 16.9 (95%CI 7.6; 26.3 metres), and 75.8 (95%CI 55.1; 96.6 metres) metres, respectively. Strength training resulted in inferior gains in 6MWT distance compared to aerobic training (WMD: -25.0; 95%CI: -49.1; -0.9). Intervention length shorter than 11 weeks (WMD: 37.0; 95%CI: -5.4; 79.3 metres) did not induce greater changes in 6MWT compared to control groups. There was a positive response in submaximal functional capacity to intradialytic training in kidney failure patients on maintenance haemodialysis.

Acute effects of graduated compression stockings on oxidative stress and muscle damage markers in garbage collectors: a randomized, crossover-controlled trial / Efeito agudo do uso de meias de compressão graduada sobre marcadores de estresse oxidative e de dano muscular em coletores de lixo: um ensaio clínico randomizado cruzado

Abstract Intense physical activity can increase oxidative stress and muscle damage in, causing fatigue and injury. Graduated compression stockings (GCS) can decrease these deleterious effects. The aim was to determine the acute effects of GCS on muscle damage and oxidative stress (OS) in garbage collectors. Thirteen garbage collectors, 25.4±5.2 years, participated using GCS or placebo stockings. Blood samples were collected at pre and post a working day and after 16 hours of rest. Markers of OS and muscle damage were evaluated. Two-way ANOVA (two conditions and two moments) was used for the analysis of the outcomes No significant differences were found for creatine kinase, catalase and glutathione peroxidase between the time and groups. There was a significant difference for the total thiol content and superoxide dismutase only in the control group (pre and post, p = 0.004). The use of GCS exerted acute protection against the increase of markers of OS, but did not contribute to attenuate muscle damage.

Resumo Atividade física intensa pode aumentar o estresse oxidativo e danos musculares, causando fadiga e lesões. As meias de compressão graduada (MCG) podem diminuir esses efeitos deletérios. O objetivo foi determinar os efeitos agudos da MCG no dano muscular e estresse oxidativo (EO) em coletores de lixo. Treze coletores de lixo, 25,4 ± 5,2 anos, participaram usando MCG ou placebo. As amostras de sangue foram coletadas antes e após um dia útil e após 16 horas de descanso. Marcadores de EO e dano muscular foram avaliados. ANOVA de duas vias (duas condições e dois momentos) foi usada para á análise dos resultados. Não foram encontradas diferenças significativas para creatina quinase, catalase e glutationa peroxidase entre o tempo e os grupos. Houve uma diferença significativa para o conteúdo total tiólico e superóxido dismutase apenas no grupo controle (pré e pós, p = 0,004). O uso de MCG exerceu proteção aguda contra o aumento de marcadores de EO, mas não contribuiu para atenuar danos musculares

Does Intradialytic Exercise Improve Removal of Solutes by Hemodialysis? A Systematic Review and Meta-analysis.

OBJECTIVE: To describe a systematic review and meta-analysis to identify if intradialytic exercise improves the removal of solutes and the hemodialysis adequacy. DATA SOURCES: A systematic review and meta-analysis of randomized controlled trials (RCTs) were performed. The sources were MEDLINE (via PubMed), Web of Science, LILACS, and SciELO, from inception until July 2018. STUDY SELECTION: Clinical trials including patients on chronic hemodialysis submitted to the intervention of aerobic intradialytic exercise. DATA EXTRACTION: Evaluating as outcomes the removal of solutes (creatinine, phosphate, potassium) and/or adequacy parameters (Kt/V-urea). DATA SYNTHESIS: The systematic review included 23 studies (7 evaluating the effect of 1 exercise session and 16 evaluating the effect of training, lasting from 6 to 25 weeks). Eleven RCT were included in the meta-analyses. It was observed that the aerobic intradialytic exercise increased the Kt/V-urea (0.15; 95% confidence interval [95% CI], 0.08-0.21) and decreased creatinine (-1.82 mg/dL; 95% CI, -2.50 to -1.13), despite the high heterogeneity of the analysis. No differences were found in phosphorus and potassium removal. CONCLUSION: The aerobic intradialytic exercise may be suggested to improve the Kt/V-urea and the creatinine removal during the dialysis.

Combined resistance and aerobic exercise is better than resistance training alone to improve functional performance of haemodialysis patients--results of a randomized controlled trial.

BACKGROUND AND PURPOSE: This study aims to compare the effects of combined resistance and aerobic exercise with a resistance programme alone on functional performance among haemodialysis patients. DESIGN: The design was a randomized controlled trial. SETTING: The setting was the dialysis unit of a Brazilian university hospital. PATIENTS: Haemodialysis patients were assigned to one kind of intervention or another. INTERVENTION: The patients were assigned to receive the resistance exercise combined with an aerobic training or to maintain an ongoing resistance programme alone for a period of 10 weeks. MAIN OUTCOME MEASURE: The functional performance of patients was assessed before and after the intervention through the 6-minute walk test (6MWT). The difference over time of the 6MWT was compared between the groups through two-way repeated-measures ANOVA. RESULTS: Thirteen patients were allocated for each group of intervention. The difference in distance walked before and after intervention in the combined training group was of +39.7 ± 61.4 m, and the difference in the resistance training group was of -19.2 ± 53.9 m, p = 0.02. CONCLUSIONS: Although the best protocol of exercise for patients on dialysis is not yet clear, in our sample of haemodialysis patients the combination of aerobic and resistance training was more effective than resistance training alone to improve functional performance.

Insulin receptor tyrosine kinase activity and substrate 1 (IRS-1) expression in human myometrium and leiomyoma.

BACKGROUND: Uterine leiomyomas are the commonest tumors of the genital tract. Growth factors seem to be implicated in the development of leiomyoma. OBJECTIVE: To determine the insulin receptor (IR) tyrosine kinase activity--phosphorylation of exogenous substrate poly(Glu 4: Tyr 1)--and insulin receptor substrate 1 expression in normal myometrium and leiomyoma. STUDY DESIGN: The study group consisted of 12 women with leiomyoma undergoing routine hysterectomy. Samples of leiomyoma and adjacent normal myometrium were obtained at the time of operation. Plasma membrane fractions were prepared and samples were incubated with and without insulin and incubated with exogenous substrate poly(Glu 4: Tyr 1). IRS-1 expression was studied in the whole lysate via Western blotting using specific antibodies. Data were analyzed using Student's t-test. RESULTS: The phosphorylation of the exogenous substrate poly(Glu 4: Tyr 1) in myometrium (1.566+/-0.177) and in leiomyoma (1.98+/-0.612) were similar (P=0.774). The IRS-1 levels in myometrium (0.190+/-0.022) and in leiomyoma (0.226+/-0.022) were not different (P=0.184). CONCLUSIONS: There was no difference in IR tyrosine kinase activity (phosphorylation of exogenous substrate) and IRS-1 expression between normal myometrium and leiomyomata. Other steps in the insulin signaling cascade require further study to investigate the role of insulin receptor in leiomyomata.