Intramuscular adipose tissue, muscle area, and power as predictors of performance in breast cancer survivors.

PURPOSE: The decline in physical performance, assessed by physical tests such as the timed up and go (TUG) test, is a consequence of reduced physiological reserves at higher levels of a hierarchical process. This occurs due to changes in muscle architecture, including atrophy and fat infiltration into the muscles, which in turn lead to changes in muscle function, resulting in reduced muscle strength and power and, consequently, affecting physical performance. This study investigated predictive factors for physical performance in breast cancer survivor (BCS), focusing on intramuscular adipose tissue (IMAT), quadríceps muscle area (QMA), and muscular power. METHODS: This observational, analytical, and cross-sectional study included 23 women without a history of cancer (age, 58.5 ± 8.3 years; BMI, 27.2 ± 5.1 kg/m2) and 56 BCS (age, 58.5 ± 8.3 years; BMI, 27.2 ± 5.1 kg/m2). QMA and IMAT were assessed using computed tomography images. Muscular power and physical performance were measured using the 5-repetition sit-to-stand and TUG tests, respectively. RESULTS: IMAT (r = 0.4, P < 0.01) and muscular power (r = - 0.4, P < 0.01) were associated with TUG performance in BCS, whereas QMA (r = - 0.22, P = 0.10) showed no significant association. QMA (r = 0.55, P < 0.01) was associated with muscular power, while no significant association was found between IMAT and muscular power (r = - 0.05, P = 0.73). Age explained 19% (P < 0.01) of TUG performance variability. Adding muscular power increased explanatory power by 12% (P < 0.01), and including IMAT further increased it by 7% (P = 0.02) for TUG performance. Collectively, age, muscular power, and IMAT accounted for 38% of the performance variance in the TUG test (age, B = 0.06, P = 0.043; muscular power, B = - 0.01, P = 0.002; IMAT, B = - 0.05, P = 0.020). CONCLUSIONS: Our findings suggest that IMAT and muscular power predict the physical performance of BCS, while QMA does not have the same predictive capability.

Clinical characteristics and outcomes of COVID-19 patients with preexisting dementia: a large multicenter propensity-matched Brazilian cohort study.

BACKGROUND: Although dementia has emerged as an important risk factor for severe SARS-CoV-2 infection, results on COVID-19-related complications and mortality are not consistent. We examined the clinical presentations and outcomes of COVID-19 in a multicentre cohort of in-hospital patients, comparing those with and without dementia. METHODS: This retrospective observational study comprises COVID-19 laboratory-confirmed patients aged ≥ 60 years admitted to 38 hospitals from 19 cities in Brazil. Data were obtained from electronic hospital records. A propensity score analysis was used to match patients with and without dementia (up to 3:1) according to age, sex, comorbidities, year, and hospital of admission. Our primary outcome was in-hospital mortality. We also assessed admission to the intensive care unit (ICU), invasive mechanical ventilation (IMV), kidney replacement therapy (KRT), sepsis, nosocomial infection, and thromboembolic events. RESULTS: Among 1,556 patients included in the study, 405 (4.5%) had a diagnosis of dementia and 1,151 were matched controls. When compared to matched controls, patients with dementia had a lower frequency of dyspnoea, cough, myalgia, headache, ageusia, and anosmia; and higher frequency of fever and delirium. They also had a lower frequency of ICU admission (32.7% vs. 47.1%, p < 0.001) and shorter ICU length of stay (7 vs. 9 days, p < 0.026), and a lower frequency of sepsis (17% vs. 24%, p = 0.005), KRT (6.4% vs. 13%, p < 0.001), and IVM (4.6% vs. 9.8%, p = 0.002). There were no differences in hospital mortality between groups. CONCLUSION: Clinical manifestations of COVID-19 differ between older inpatients with and without dementia. We observed that dementia alone could not explain the higher short-term mortality following severe COVID-19. Therefore, clinicians should consider other risk factors such as acute morbidity severity and baseline frailty when evaluating the prognosis of older adults with dementia hospitalised with COVID-19.

Patients hospitalized with active tuberculosis and Covid-19 coinfection: A matched case-control from the Brazilian Covid-19 Registry.

Although control of Covid-19 has improved, the virus continues to cause infections, such as tuberculosis, that is still endemic in many countries, representing a scenario of coinfection. To compare Covid-19 clinical manifestations and outcomes between patients with active tuberculosis infection and matched controls. This is a matched case-control study based on data from the Brazilian Covid-19 Registry, in hospitalized patients aged 18 or over with laboratory confirmed Covid-19 from March 1, 2020, to March 31, 2022. Cases were patients with tuberculosis and controls were Covid-19 patients without tuberculosis. From 13,636 Covid-19, 36 also had active tuberculosis (0.0026%). Pulmonary fibrosis (5.6% vs 0.0%), illicit drug abuse (30.6% vs 3.0%), alcoholism (33.3% vs 11.9%) and smoking (50.0% vs 9.7%) were more common among patients with tuberculosis. They also had a higher frequency of nausea and vomiting (25.0% vs 10.4%). There were no significant differences in in-hospital mortality, mechanical ventilation, need for dialysis and ICU stay. Patients with TB infection presented a higher frequency of pulmonary fibrosis, abuse of illicit drugs, alcoholism, current smoking, symptoms of nausea and vomiting. The outcomes were similar between them.

Mechanical ventilation and death in pregnant patients admitted for COVID-19: a prognostic analysis from the Brazilian COVID-19 registry score.

BACKGROUND: The assessment of clinical prognosis of pregnant COVID-19 patients at hospital presentation is challenging, due to physiological adaptations during pregnancy. Our aim was to assess the performance of the ABC2-SPH score to predict in-hospital mortality and mechanical ventilation support in pregnant patients with COVID-19, to assess the frequency of adverse pregnancy outcomes, and characteristics of pregnant women who died. METHODS: This multicenter cohort included consecutive pregnant patients with COVID-19 admitted to the participating hospitals, from April/2020 to March/2022. Primary outcomes were in-hospital mortality and the composite outcome of mechanical ventilation support and in-hospital mortality. Secondary endpoints were pregnancy outcomes. The overall discrimination of the model was presented as the area under the receiver operating characteristic curve (AUROC). Overall performance was assessed using the Brier score. RESULTS: From 350 pregnant patients (median age 30 [interquartile range (25.2, 35.0)] years-old]), 11.1% had hypertensive disorders, 19.7% required mechanical ventilation support and 6.0% died. The AUROC for in-hospital mortality and for the composite outcome were 0.809 (95% IC: 0.641-0.944) and 0.704 (95% IC: 0.617-0.792), respectively, with good overall performance (Brier = 0.0384 and 0.1610, respectively). Calibration was good for the prediction of in-hospital mortality, but poor for the composite outcome. Women who died had a median age 4 years-old higher, higher frequency of hypertensive disorders (38.1% vs. 9.4%, p < 0.001) and obesity (28.6% vs. 10.6%, p = 0.025) than those who were discharged alive, and their newborns had lower birth weight (2000 vs. 2813, p = 0.001) and five-minute Apgar score (3.0 vs. 8.0, p < 0.001). CONCLUSIONS: The ABC2-SPH score had good overall performance for in-hospital mortality and the composite outcome mechanical ventilation and in-hospital mortality. Calibration was good for the prediction of in-hospital mortality, but it was poor for the composite outcome. Therefore, the score may be useful to predict in-hospital mortality in pregnant patients with COVID-19, in addition to clinical judgment. Newborns from women who died had lower birth weight and Apgar score than those who were discharged alive.

Temporal validation of the MMCD score to predict kidney replacement therapy and in-hospital mortality in COVID-19 patients.

BACKGROUND: Acute kidney injury has been described as a common complication in patients hospitalized with COVID-19, which may lead to the need for kidney replacement therapy (KRT) in its most severe forms. Our group developed and validated the MMCD score in Brazilian COVID-19 patients to predict KRT, which showed excellent performance using data from 2020. This study aimed to validate the MMCD score in a large cohort of patients hospitalized with COVID-19 in a different pandemic phase and assess its performance to predict in-hospital mortality. METHODS: This study is part of the "Brazilian COVID-19 Registry", a retrospective observational cohort of consecutive patients hospitalized for laboratory-confirmed COVID-19 in 25 Brazilian hospitals between March 2021 and August 2022. The primary outcome was KRT during hospitalization and the secondary was in-hospital mortality. We also searched literature for other prediction models for KRT, to assess the results in our database. Performance was assessed using area under the receiving operator characteristic curve (AUROC) and the Brier score. RESULTS: A total of 9422 patients were included, 53.8% were men, with a median age of 59 (IQR 48-70) years old. The incidence of KRT was 8.8% and in-hospital mortality was 18.1%. The MMCD score had excellent discrimination and overall performance to predict KRT (AUROC: 0.916 [95% CI 0.909-0.924]; Brier score = 0.057). Despite the excellent discrimination and overall performance (AUROC: 0.922 [95% CI 0.914-0.929]; Brier score = 0.100), the calibration was not satisfactory concerning in-hospital mortality. A random forest model was applied in the database, with inferior performance to predict KRT requirement (AUROC: 0.71 [95% CI 0.69-0.73]). CONCLUSION: The MMCD score is not appropriate for in-hospital mortality but demonstrates an excellent predictive ability to predict KRT in COVID-19 patients. The instrument is low cost, objective, fast and accurate, and can contribute to supporting clinical decisions in the efficient allocation of assistance resources in patients with COVID-19.

Greater Gastrocnemius Muscle Hypertrophy After Partial Range of Motion Training Performed at Long Muscle Lengths.

ABSTRACT: Kassiano, W, Costa, B, Kunevaliki, G, Soares, D, Zacarias, G, Manske, I, Takaki, Y, Ruggiero, MF, Stavinski, N, Francsuel, J, Tricoli, I, Carneiro, MAS, and Cyrino, ES. Greater gastrocnemius muscle hypertrophy after partial range of motion training performed at long muscle lengths. J Strength Cond Res 37(9): 1746-1753, 2023-Whether there is an optimal range of motion (ROM) to induce muscle hypertrophy remains elusive, especially for gastrocnemius. This study aimed to compare the changes in gastrocnemius muscle thickness between calf raise exercise performed with full ROM (FULL ROM ), partial ROM performed in the initial (INITIAL ROM ), and final (FINAL ROM ) portions of the ROM. Forty-two young women performed a calf training program for 8 weeks, 3 days·week -1 , with differences in the calf raise ROM configuration. The calf raise exercise was performed in a pin-loaded, horizontal, leg-press machine, in 3 sets of 15-20 repetition maximum. The subjects were randomly assigned to 1 of the 3 groups: FULL ROM (ankle: -25° to +25°), INITIAL ROM (ankle: -25° to 0°), and FINAL ROM (ankle: 0° to +25°), where 0° was defined as an angle of 90° of the foot with the tibia. The muscle thickness measurements of medial and lateral gastrocnemius were taken by means of B-mode ultrasound. INITIAL ROM elicited greater medial gastrocnemius increases than FULL ROM and FINAL ROM (INITIAL ROM = +15.2% vs. FULL ROM = +6.7% and FINAL ROM = +3.4%; p ≤ 0.009). Furthermore, INITIAL ROM elicited greater lateral gastrocnemius increases than FINAL ROM (INITIAL ROM = +14.9% vs. FINAL ROM = +6.2%; p < 0.024) but did not significantly differ from FULL ROM (FULL ROM = +7.3%; p = 0.060). The current results suggest that calf training performed at longer muscle lengths may optimize gastrocnemius muscle hypertrophy in young women. Therefore, when prescribing hypertrophy-oriented training, the inclusion of the calf raise exercise performed with partial ROM in the initial portion of the excursion should be considered.

Muscle Swelling of the Triceps Surae in Response to Straight-Leg and Bent-Leg Calf Raise Exercises in Young Women.

ABSTRACT: Kassiano, W, Costa, B, Kunevaliki, G, Soares, D, Stavinski, N, Francsuel, J, Carneiro, MAS, Tricoli, I, Nunes, JP, Ribeiro, AS, and Cyrino, ES. Muscle swelling of the triceps surae in response to straight-leg and bent-leg calf raise exercises in young women. J Strength Cond Res 37(7): e438-e443, 2023-Triceps surae muscle swelling in response to different resistance exercises remains to be determined. This study compared the effects of straight-leg (STRA-leg) calf raise vs. bent-leg (BENT-leg) calf raise exercises on triceps surae muscle swelling. Seventeen young women (23.7 ± 4.0 years; 67.4 ± 16.0 kg; and 163.5 ± 7.2 cm) performed 2 resistance training sessions; in one, they performed the STRA-leg calf raise, and in another, they performed the BENT-leg calf raise. A randomized, cross-over, and counterbalanced design was adopted for this investigation. The subjects performed 4 sets of 20 repetitions maximum until concentric muscular failure. The muscle thickness of the gastrocnemius medial (GM), gastrocnemius lateral (GL), and soleus (SOL) was taken through B-mode ultrasound before and immediately after the calf raise exercises. STRA-leg calf raise elicited greater increases in muscle thickness of GM (+8.8% vs. -0.9%, p < 0.001) and GL (+14.5% vs. +7.0%, p < 0.001) than BENT-leg calf raise. Conversely, BENT-leg calf raise elicited greater increases in SOL muscle thickness than STRA-leg calf raise (+15.4% vs. +7.7%, p < 0.001). From a practical perspective, the STRA-leg calf raise should be preferred if the aim is stimulating the 3 muscles that comprise the triceps surae, whereas the BENT-leg calf raise should be prioritized if the target muscle is the SOL.

Development and validation of the MMCD score to predict kidney replacement therapy in COVID-19 patients.

BACKGROUND: Acute kidney injury (AKI) is frequently associated with COVID-19, and the need for kidney replacement therapy (KRT) is considered an indicator of disease severity. This study aimed to develop a prognostic score for predicting the need for KRT in hospitalised COVID-19 patients, and to assess the incidence of AKI and KRT requirement. METHODS: This study is part of a multicentre cohort, the Brazilian COVID-19 Registry. A total of 5212 adult COVID-19 patients were included between March/2020 and September/2020. Variable selection was performed using generalised additive models (GAM), and least absolute shrinkage and selection operator (LASSO) regression was used for score derivation. Accuracy was assessed using the area under the receiver operating characteristic curve (AUC-ROC). RESULTS: The median age of the model-derivation cohort was 59 (IQR 47-70) years, 54.5% were men, 34.3% required ICU admission, 20.9% evolved with AKI, 9.3% required KRT, and 15.1% died during hospitalisation. The temporal validation cohort had similar age, sex, ICU admission, AKI, required KRT distribution and in-hospital mortality. The geographic validation cohort had similar age and sex; however, this cohort had higher rates of ICU admission, AKI, need for KRT and in-hospital mortality. Four predictors of the need for KRT were identified using GAM: need for mechanical ventilation, male sex, higher creatinine at hospital presentation and diabetes. The MMCD score had excellent discrimination in derivation (AUROC 0.929, 95% CI 0.918-0.939) and validation (temporal AUROC 0.927, 95% CI 0.911-0.941; geographic AUROC 0.819, 95% CI 0.792-0.845) cohorts and good overall performance (Brier score: 0.057, 0.056 and 0.122, respectively). The score is implemented in a freely available online risk calculator ( https://www.mmcdscore.com/ ). CONCLUSIONS: The use of the MMCD score to predict the need for KRT may assist healthcare workers in identifying hospitalised COVID-19 patients who may require more intensive monitoring, and can be useful for resource allocation.

Functional high-intensity interval training is not equivalent when compared to combined training for blood pressure improvements in postmenopausal women: a randomized controlled trial.

INTRODUCTION: Low-volume functional high-intensity interval training (F-HIIT) improves cardiorespiratory fitness, body composition, and physical function similarly to combined training (CT, gold standard protocol), however no previous studies have compared the F-HIIT equivalence with CT in reducing blood pressure in older people, particularly in postmenopausal women (PW). Therefore, the aim of this study (trial registration: NCT03200639) was designed to test whether F-HIIT of low volume is an equivalent strategy to CT for improving blood pressure (BP) in PW. MATERIAL AND METHOD: Forty-nine PW were divided into two groups: F-HIIT and CT. The F-HIIT protocol was composed of 10 sets of 60 seconds of high-intensity exercises interspersed with 60 seconds of low-intensity exercises for recovery. The CT protocol was composed of 30 minutes of moderate-intensity walking, followed by five total body resistance exercises. Both protocols were performed 3-times-a-week for 12 weeks. The BP from rest condition (before exercise) was measured before and after 12 weeks of intervention in both groups, using an automatic blood pressure monitor. The boundaries values for equivalence for systolic and diastolic BP was set at 5.14 and 2.92 mmHg, respectively. RESULTS: There was only a significant reduction (P < .05) in systolic BP in CT group from baseline (-3.2 (95% CI, -6.2 to -0.2) mmHg). The difference of systolic BP between F-HIIT and CT was 5.8 (95% CI, 1.3-10.4) mmHg, showing non-equivalence (inferiority) for F-HIIT. CONCLUSION: Thus, these results suggest that low-volume F-HIIT protocol is not an equivalent strategy when compared to CT for BP improvements in PW.

Weaker older women gain more lower body strength than their stronger counterparts, but not muscle mass, following 12 weeks of resistance training.

We compared the magnitude of strength and muscle mass changes in response to resistance training (RT) between stronger older women and their weaker counterparts. Older women (n = 207) were grouped into tertiles according to their baseline muscular strength index. The upper and lower tertiles participants were categorized as stronger (STR, n = 69) and weaker (WKR, n = 69), respectively. Both groups engaged in a 12-week whole-body RT program. Outcomes included one-repetition maximum (1RM) tests in the three lifts and assessment of segmental lean soft tissue (LST) and skeletal muscle mass (SMM). The 1RM increase was similar between groups for the chest press [between-groups effect size of the differences (ESdiff) and 95% confidence interval (95%CI) = 0.10 (95%CI: -0.52, 0.31), P = 0.617] and preacher curl [ESdiff = 0.08 (95%CI: -0.48, 0.32), P = 0.681]. Changes were greater in WKR than STR for 1RM leg extension [ESdiff = -0.45 (95%CI: -0.86, -0.04), P = 0.030]. The increases of segmental LST and SMM were similar between-groups (ESdiff contains zero, P ≥ 0.434). We conclude that stronger and weaker older women benefit similarly for muscle mass and upper-limb strength gains. Notably, weaker older women may experience greater lower-limbs strength gains.

Effects of Resistance Training at Different Loads on Inflammatory Biomarkers, Muscle Mass, Muscular Strength, and Physical Performance in Postmenopausal Women.

ABSTRACT: Carneiro, MAS, de Oliveira Júnior, GN, de Sousa, JFR, Murta, EFC, Orsatti, CL, Michelin, MA, Cyrino, ES, and Orsatti, FL. Effects of resistance training at different loads on inflammatory biomarkers, muscle mass, muscular strength, and physical performance in postmenopausal women. J Strength Cond Res 36(6): 1582-1590, 2022-It has been suggested that the effect of resistance training (RT) on circulating proinflammatory biomarkers may be dependent on muscle mass gain. A few recent studies have suggested that lower-load RT (LLRT; loads <50% of 1 repetition maximum [1RM] and repetition performed until, or close to, voluntary concentric failure) may be superior to higher-load RT (HLRT; loads >70% of 1RM) in increasing muscle mass. Hence, this study aimed to test whether LLRT is superior to HLRT for increasing muscle mass (total fat-free mass [TFFM] and leg fat-free mass [LFFM]) and improving circulating inflammatory biomarkers (interleukin [IL]-6, IL1-ra, tumor necrosis factor [TNF]-α, and extracellular heat shock protein [eHSP]70) in postmenopausal women (PW) (primary outcome). The secondary outcome was to compare the changes in muscular strength and physical performance (4-meter walking test [4-M], timed-up-and-go [TUG] test, and sit-to-stand [STS] test) between the LLRT and HLRT. The PW were randomized into 2 groups: LLRT (n = 14; loads necessary to perform 30-35 repetitions) and HLRT (n = 15; loads necessary to perform 8-12 repetitions). The greater magnitude of increase in LFFM (p = 0.033) was observed in LLRT when compared with HLRT. Moreover, there was a trend for a greater increase in TFFM in LLRT over HLRT (p = 0.070). However, there were similar improvements in TNF-α and muscular strength (p < 0.001). Furthermore, there was no significant difference between the RT schemes on IL-6, IL-1ra, and eHSP70 levels. Thus, although performing LLRT until, or close to, voluntary concentric failure seems to provide a greater stimulus for an increase in muscle mass than HLRT, it does not seem to affect the responses in circulating inflammatory biomarkers, muscular strength, and physical performance in PW.

Resistance Training Volume Enhances Muscle Hypertrophy, but Not Strength in Postmenopausal Women: A Randomized Controlled Trial.

ABSTRACT: Nascimento de Oliveira Júnior, G, de Freitas Rodrigues de Sousa, J, Augusto da Silva Carneiro, M, Martins, FM, Santagnello, SB, Campos Souza, MV, and Orsatti, FL. Resistance training volume enhances muscle hypertrophy, but not strength in postmenopausal women: a randomized controlled trial. J Strength Cond Res 36(5): 1216-1221, 2022-Among several possible resistance training (RT) variables to be manipulated, the training volume has been considered as a critical variable to maximize RT-induced hypertrophy. Many of the studies that compared one set of RT with 3 sets have failed to show a difference in muscle hypertrophy in older adults. However, it is not clear whether further increases in RT volume (i.e., 6 sets) would result in even greater RT-related hypertrophy than 3 sets in older adults. This study aimed to investigate whether higher-volume RT (HV-RT) maximizes gains in lean body mass and muscle strength (MS) when compared with lower-volume RT (LV-RT) in postmenopausal women (PW). Fifty-eight PW were randomized into 1 of the 3 groups: control group (CT, no exercise), HV-RT (6 sets per exercise), and LV-RT (3 sets per exercise). Volunteers took part in a supervised training program (leg press 45°, leg extension, leg curl and standing calf raises) and were assessed for leg lean mass (LLM; dual X-ray absorptiometry) and lower limb MS (leg press and leg extension; 1 repetition maximum [1RM]) before and after 12 weeks of RT. Both HV-RT and LV-RT groups increased (p < 0.05) LLM and MS when compared with the CT group. Higher increases in LLM gains were observed for the HV-RT group when compared with the LV-RT group (6.1 and 2.3%, p < 0.001). Both HV-RT and LV-RT groups similarly increased 1RM in the leg press and leg extension. Thus, there seems to be a dose-response relationship between RT volume and muscle hypertrophy, but not for MS gains in PW.

[Social distancing as protection factor against COVID-19 in a non-metropolitan area in the State of Rio Grande do Sul, BrazilLas medidas de distanciamiento social como factor de protección contra la COVID-19 en el interior de Rio Grande do Sul, Brasil]. / Medidas de distanciamento social como fator de proteção contra a COVID-19 no interior do Rio Grande do Sul, Brasil.

OBJECTIVE: To estimate the SARS-CoV-2 seroprevalence in a non-metropolitan area (Vale do Rio Pardo) in the state of Rio Grande do Sul, Brazil, and determine the association between seroprevalence and adherence to social distancing measures. METHOD: For the present population-based, cross-sectional study, data were collected in four stages from August to October 2020. SARS-CoV-2 seroprevalence was assessed using an IgG/IgM rapid test. Demographic, socioeconomic, clinical, and behavioral data were also collected, with administration of a three-question survey to determine adherence to social distancing measures with a focus on the level of social distancing practiced by participants, their routine activities, and circulation of people in the home. The association between sociodemographic data and social distancing was assessed using the chi-square test for linear trends in proportions, and the association between social distancing and seroprevalence was assessed using Poisson regression (95% confidence interval [95%CI]; P< 0.05). RESULTS: Of 4 252 tested and interviewed participants, 11.8% (95%CI: 10.8; 12.8) did not adhere to social distancing measures. The prevalence of a positive rapid test was 4.7% in participants who did not practice social distancing and 1.9% in participants who adhered to social distancing measures (P< 0.05). The variables male sex, age 20 to 59 years, having completed high school, monthly family income ranging from R$ 3 136.00 to R$ 6 270.00, and living in rural areas were associated with non-adherence to social distancing (P< 0.05). Adherence to all social distancing measures provided protection against SARS-CoV-2 infection (prevalence ratio: 0.37; 95%CI: 0.19; 0.73). CONCLUSIONS: The results indicate a reduction in seroprevalence with the adherence to social distancing measures.

OBJETIVO: Investigar la seroprevalencia del SARS-CoV-2 en la zona del Vale do Rio Pardo (Rio Grande do Sul, Brasil), y analizar la relación entre la seroprevalencia y el cumplimiento de las medidas de distanciamiento social por parte de la población. MÉTODO: Este estudio transversal basado en la población comprendió cuatro etapas de recopilación domiciliaria de datos entre agosto y octubre del 2020. La seroprevalencia se evaluó con la prueba rápida de anticuerpos IgM e IgG. Además, se recopilaron datos demográficos, socioeconómicos, clínicos y comportamentales por medio de un cuestionario de tres preguntas sobre el cumplimiento de las medidas de distanciamiento social, centrado en el grado de distanciamiento social que la persona entrevistada lograba tener, la rutina de las actividades de la persona entrevistada y la circulación de personas en el hogar. La relación entre los datos sociodemográficos y la práctica de distanciamiento social se evaluó con la prueba del ji cuadrado para determinar la tendencia lineal y la heterogeneidad de las proporciones, y la relación entre el distanciamiento social y la seroprevalencia se evaluó con el modelo de regresión de Poisson (intervalo de confianza de 95% [IC95%]; P< 0,05). RESULTADOS: De las 4 252 personas que se entrevistaron y a las que se les realizó la prueba, 11,8% (IC95%: 10,8; 12,8) no cumplían el distanciamiento social. La prevalencia de la realización de la prueba rápida con reactivo fue de 4,7% entre quienes no cumplían el distanciamiento social y de 1,9% entre quienes cumplían con esa medida (P< 0,05). Las variables relacionadas con el sexo masculino, el grupo etario de 20 a 59 años, la escolaridad de nivel medio, los ingresos familiares mensuales de R$ 3 136,00 a R$ 6 270,00 y la residencia en zonas urbanas guardaron relación con el incumplimiento del distanciamiento social (P< 0,05). El cumplimiento con todas las medidas de distanciamiento social fue un factor de protección contra la infección por SARS-CoV-2 (razón de prevalencia: 0,37; IC95%: 0,19; 0,73). CONCLUSIONES: Los resultados indican una reducción de la seroprevalencia a causa de las medidas de distanciamiento social.

Influence of High- and Low-Frequency Resistance Training on Lean Body Mass and Muscle Strength Gains in Untrained Men.

ABSTRACT: Franco, CMC, Carneiro, MAS, de Sousa, JFR, Gomes, GK, and Orsatti, FL. Influence of high- and low-frequency resistance training on lean body mass and muscle strength gains in untrained men. J Strength Cond Res 35(8): 2089-2094, 2021-The aim of this study was to investigate whether high-frequency resistance training (HFRT) performs better in lean body mass (LBM) and muscle strength gains when compared with low-frequency resistance training (LFRT). Eighteen untrained males (height: 1.76 ± 0.05 m, body mass: 78.3 ± 13.5 kg, and age: 22.1 ± 2.2 years) were randomly allocated into HFRT (n = 9) and LFRT (n = 9). Muscle strength {1 repetition maximum (RM) (bench press [BP] and unilateral leg extension [LE])} and LBM (DXA) were assessed at before and after 8 weeks of training. Both groups performed 7 whole-body resistance exercises, standardized to 10 sets per week, 8-12 maximal repetitions, and 90-120 seconds of rest in a 5-day resistance training routine. The LFRT performed a split-body routine, training each specific muscle group once a week. The HFRT performed a total-body routine, training all muscle groups every session and progressed from a training frequency of once per week to a training frequency of 5 times per week. Lean body mass increased without differences between groups (HFRT = 1.0 kg vs. LFRT = 1.5 kg; p = 0.377). Similarly, 1RM increased without differences between groups (right LE, HFRT = 21.2 kg vs. LFRT = 19.7 kg, p = 0.782; BP, HFRT = 7.1 kg vs. LFRT = 4.5 kg, p = 0.293). These findings suggest that in young untrained men, progressing from a training frequency of once per week to a training frequency of 5 times per week with equated volume produces similar gains in LBM and muscle strength as a constant training frequency of once per week, over an 8-week training period.

Lower-Load is More Effective Than Higher-Load Resistance Training in Increasing Muscle Mass in Young Women.

Franco, CMdC, Carneiro, MAdS, Alves, LTH, Júnior, GNdO, de Sousa, JdFR, and Orsatti, FL. Lower-load is more effective than higher-load resistance training in increasing muscle mass in young women. J Strength Cond Res 33(7S): S152-S158, 2019-This study was designed to investigate the impact of load (higher vs. lower) performed until or close to volitional fatigue on muscle strength (MS) and fat and bone-free lean mass (FBFM) in young women. To do this, 32 women performed resistance training (RT) in 1 of 2 conditions: lower-load RT (LL; n = 14, age = 24.3 ± 4.8 years and body mass index [BMI] = 23.3 ± 2.8 kg·m) and higher-load RT (HL; n = 18, age = 23.0 ± 3.3 years and BMI = 22.4 ± 3.3 kg·m). Leg FBFM (DXA) and MS (1 repetition maximum-unilateral leg extension [LE]) were evaluated before and after 9 weeks (the first week was used for familiarization) of RT. Both groups performed 3 unilateral exercises (LE, leg curl, and leg press), 3 sets per exercise, 60-90 seconds of rest between sets, 2 days per week. In the LL group, the loads used in the exercises were the loads necessary to perform 30-35 repetitions in the first set. For the HL group, the loads used were the loads necessary to perform 8-10 repetitions in the first set. The LL group showed higher RT volume than the HL. Both groups showed leg muscle mass gains (p < 0.05). However, the LL group was better [p = 0.032 and effect size (eta = 0.14 [large]) than the HL group in leg FBFM gains (LL = 0.3 kg [IC 95%: 0.4 kg; 0.2 kg] and HL = 0.1 kg [IC 95%: 0.2 kg; 0.0 kg]). Both groups showed MS gains, without any difference between them (LL = 3.4 kg [IC 95%: 4.4 kg; 2.5 kg] and HL = 4.2 kg [IC 95%: 5.1 kg; 3.3 kg]; p = 0.239). Thus, lower-load RT is more effective than higher-load RT in increasing FBFM, but not MS in novice young women.

Propulsive forces and muscle activation during gait: comparisons between premenopausal and postmenopausal midlife women.

OBJECTIVE: The aim of this study was to investigate whether there is a reduction in propulsive force during gait in postmenopausal women compared with premenopausal women. METHODS: Forty-four women (21 premenopausal and 23 postmenopausal women) aged 40 to 55 years were selected. The ability to reach peak propulsive forces was assessed during the step execution test. The test was performed at the usual speed on 2 nonconsecutive days, with two attempts per day, using a force platform. Four temporal parameters were defined and calculated: initiation phase, preparation phase, swing phase, and total time. Peak force (anteroposterior and vertical) and time to reach peak force were obtained in both preparation and swing phases. The rate of force development was defined as peak force divided by time to reach peak force. RESULTS: The postmenopausal women group presented a longer time in the preparation phase (540.6 ± 77 ms vs 482.5 ± 93 ms, P = 0.024) and consequently a longer total time in the step execution test (1,191 ± 106.4 ms vs 1,129 ± 114.3 ms, P = 0.045). There were differences between the groups for the rate of force development in the anteroposterior (postmenopausal women, 142.5 ± 38.1 N/s vs premenopausal women, 174.7 ± 70.5 N/s; P = 0.022) and vertical directions in the preparation phase (postmenopausal women, 102.7 ± 62.3 N/s vs premenopausal women, 145.3 ± 71 N/s; P = 0.012). No significant differences ( P > 0.05) were found in force, time to peak force, and rate of force development during the swing phase. In addition, there were no observed differences in surface electromyography of the medial and lateral gastrocnemius muscles during the preparation phase and swing phase of the step execution test between the two groups. CONCLUSIONS: Postmenopausal women exhibited lower ability to generate propulsive force rapidly (rates of force development) in both the anteroposterior and vertical directions during the preparation phase of gait compared with premenopausal women. This indicates that postmenopausal women experience a reduction in propulsive force during gait.

Full-body resistance training promotes greater fat mass loss than a split-body routine in well-trained males: A randomized trial.

While significant progress has been made in understanding the resistance training (RT) strategy for muscle hypertrophy increase, there remains limited knowledge about its impact on fat mass loss. This study aimed to investigate whether full-body is superior to split-body routine in promoting fat mass loss among well-trained males. Twenty-three participants were randomly assigned to 1 of 2 groups: full-body (n = 11, training muscle groups 5 days per week) and split-body (n = 12, training muscle groups 1 day per week). Both groups performed a weekly set volume-matched condition (75 sets/week, 8-12 repetition maximum at 70%-80 % of 1RM) for 8 weeks, 5 days per week with differences only in the routine. Whole-body and regional fat were assessed using DXA at the beginning and at the end of the study. Full-body RT elicited greater losses compared to split-body in whole-body fat mass (-0.775 ± 1.120 kg vs. +0.317 ± 1.260 kg; p = 0.040), upper-limb fat mass (-0.085 ± 0.118 kg vs. +0.066 ± 0.162 kg; p = 0.019), gynoid fat mass (-0.142 ± 0.230 kg vs. +0.123 ± 0.230 kg; p = 0.012), lower-limb fat mass (-0.197 ± 0.204 kg vs. +0.055 ± 0.328 kg; p = 0.040), and a trend in interaction in android fat mass (-0.116 ± 0.153 kg vs. +0.026 ± 0.174 kg; p = 0.051), with large effects sizes (η2 p ≥ 0.17). This study provides evidence that full-body is more effective in reducing whole-body and regional fat mass compared to split-body routine in well-trained males.