Resistance training with blood flow restriction and cognition in elderly women (project "forte-mente-ativa"): study protocol

Abstract Aim: In the process of aging, there is a decrease on muscle strength and cognitive function. Resistance training combined with blood flow restriction (BFRRT) has been shown capable of maintaining or improve aspects of physical health. However, the effects of BFRRT the cognitive function of the elderly are not clear. This study aimed to describe the design of a randomized controlled clinical trial, that will investigate the effects of BFRRT on cognitive function, physical performance and physiological and morphological aspects in elderly women. Methods: Forty participants will be randomized into one of the following groups: low load resistance training, blood flow restriction resistance training, moderate load resistance training or Control. All intervention groups will complete 16 weeks of resistance training, three times week (45 minutes each), with training consisting of four exercises for the upper and lower body, including three sets of ten repetitions each. No exercise will be performed by the Control group. Cognitive function will be the primary outcome of the study. Secondary outcomes will include body composition, muscle strength, functional capacity, double-task, level of physical activity, static and dynamic balance, brain activity, BDNF neurotrophic factor, anxiety, depression and sleep state). Conclusion: This project will contribute to the existing knowledge and will have a social impact regarding the use of physical exercise as a non-pharmacological tool for the mental and physical health older individuals. Trial Registration: Brazilian Registry of Clinical Trials number RBR-7BC8ZP.

Acute and Chronic Responses of Aerobic Exercise With Blood Flow Restriction: A Systematic Review.

This study systematically reviewed the available scientific evidence pertaining to the acute and chronic changes promoted by aerobic exercise (AE) combined with blood flow restriction (BFR) on neuromuscular, metabolic and hemodynamic variables. PubMed, Web of ScienceTM and Scopus databases were searched for the period from January 2000 to June 2019 and the analysis involved a critical content review. A total of 313 articles were identified, of which 271 were excluded and 35 satisfied the inclusion criteria. Twelve studies evaluated the acute effects and eight studies evaluated the chronic metabolic effects of AE + BFR. For the neuromuscular variables, three studies analyzed the acute effects of AE + BFR and nine studies analyzed the chronic effects. Only 15 studies were identified that evaluated the hemodynamic acute effects of AE + BFR. The analysis provided evidence that AE combined with BFR promotes positive acute and chronic changes in neuromuscular and metabolic variables, a greater elevation in hemodynamic variables than exercise alone, and a higher energy demand during and after exercise. Since these alterations were all well-tolerated, this method can be considered to be safe and feasible for populations of athletes, healthy young, obese, and elderly individuals.

Walking with blood flow restriction improves the dynamic strength of women with osteoporosis / Caminhada com restrição de fluxo sanguíneo melhora a força dinâmica de mulheres com osteoporose / Caminata con restricción de flujo sanguíneo mejora la fuerza dinámica de mujeres con osteoporosis

ABSTRACT Introduction: Improving strength levels is important to women with osteoporosis. Resistance and aerobic exercise are effective means of reaching this goal; however, the use of low-load exercises with blood flow restriction is an alternative to traditional methods of exercise to achieve the same strength gains in this population. Objective: To analyze the chronic effects of aerobic and resistance training combined with blood flow restriction on the maximal dynamic strength (MDS) of women with osteoporosis. Methods: Twenty women (61.40±4.63 years of age, 61.82±12.54 kg, 1.51±0.05 m, 27.16±5.55 kg/m²) were randomly assigned to four groups: 1 - high-intensity resistance training (HI); 2 - low-intensity resistance training with blood flow restriction (LI-BFR); 3 - aerobic training with blood flow restriction (ABFR); and 4 - control group (CG). Unilateral knee extension MDS was assessed using the one-repetition maximum (1RM) strength test before and after the 6th and 12th weeks of intervention. The data were analyzed using repeated measures analysis of variance (ANOVA) with a Bonferroni post-hoc test performed using SPSS (version 21.0), considering a significance level of P<0.05 for all tests. Results: Baseline comparisons showed that HI and CG had lower strength levels than LI-BFR and ABFR groups (P<0.05). The ABFR group exhibited a significant increase in MDS between the 1st and the 6th week (9%, P=0.001) and between the 1st and the 12th week (21.6%, P=0.008). The LI-BFR group exhibited increased MDS between the 1st and the 6th week (10.1%, P=0.001), between the 1st and the 12th week (24.2%, P=0.003) and between the 6th and 12th week (12.8%, P=0.030). The HI group exhibited a significant difference between the 1st and the 6th week (38.7%, P<0.001), between the 1st and the 12th week (62%, P<0.001) and between the 6th and 12th weeks (17.4%, P=0.020), whereas the CG had no significant differences between the timepoints (P>0.05). Conclusions: ABFR and LI-BFR effectively increased the MDS of women with osteoporosis.

RESUMO Introdução: Melhorar os níveis de força é importante para as mulheres com osteoporose. Os exercícios de força e aeróbicos são eficazes para atingir esse objetivo; no entanto, o uso de exercícios de baixa carga com restrição do fluxo sanguíneo é uma alternativa aos métodos tradicionais de exercício para atingir os mesmos ganhos de força nessa população. Objetivo: Analisar o efeito crônico do treinamento aeróbico e de força combinado com a restrição de fluxo sanguíneo sobre a força dinâmica máxima (FDM) de mulheres com osteoporose. Métodos: Vinte mulheres (61,40 ± 4,63 anos; 61,82 ± 12,54 kg; 1,51 ± 0,05 m; 27,16 ± 5,55 kg/m²) foram randomizadas em quatro grupos: 1 - treinamento de força de alta intensidade (AI); 2 - treinamento de força de baixa intensidade com restrição de fluxo sanguíneo (BIRFS); 3 - treinamento aeróbico com restrição de fluxo sanguíneo (ARFS) e 4 - controle (GC). A avaliação da força dinâmica máxima (FDM) da extensão unilateral do joelho foi realizada pelo teste de 1RM antes e depois da 6ª e 12ª semanas de intervenção. Para a análise dos dados realizou-se o teste ANOVA de medidas repetidas com teste de Bonferroni post-hoc no software SPSS (versão 21.0), considerando um nível de significância de P < 0,05 em todas as análises. Resultados: As comparações antes da intervenção mostraram que os grupos AI e GC tinham menores níveis de força que os grupos ARFS e BIRFS (P < 0,05). O grupo ARFS apresentou aumento significativo na FDM entre a 1ª e a 6ª (9%; P = 0,001) e entre a 1ª e a 12ª semana (21,6%; P = 0,008). O grupo BIRFS teve aumento da FDM entre a 1ª e a 6ª (10,1%; P = 0,001), entre a 1ª e a 12ª semana (24,2%; P = 0,003) e entre a 6ª e 12ª semana (12,8%; P = 0,030). O grupo AI teve diferença significativa entre a 1ª e a 6ª semana (38,7%; P < 0,001), entre a 1ª e a 12ª semana (62%; P < 0,001) e entre a 6ª e a 12ª semana (17,4%; P = 0,020), enquanto o GC não apresentou diferença entre os pontos do tempo (P > 0,05). Conclusões: ARFS e BIRFS aumentaram efetivamente a FDM em mulheres com osteoporose.

RESUMEN Introducción: Mejorar los niveles de fuerza es importante para las mujeres con osteoporosis. Los ejercicios de fuerza y aeróbicos son eficaces para alcanzar ese objetivo; sin embargo, el uso de ejercicios de baja carga con restricción del flujo sanguíneo es una alternativa a los métodos tradicionales de ejercicio para alcanzar los mismos aumentos de fuerza en esa población. Objetivo: Analizar el efecto crónico del entrenamiento aeróbico y de fuerza combinado con la restricción de flujo sanguíneo sobre la fuerza dinámica máxima (FDM) de mujeres con osteoporosis. Métodos: Veinte mujeres (61,40 ± 4,63 años; 61,82 ± 12,54 kg, 1,51 ± 0,05 m; 27,16 ± 5,55 kg / m²) fueron aleatorizadas en cuatro grupos: 1 - entrenamiento de fuerza de alta intensidad (AI); 2 - entrenamiento de fuerza de baja intensidad con restricción del flujo sanguíneo (BIRFS); 3 - entrenamiento aeróbico con restricción del flujo sanguíneo (ARFS) y 4 - Control (GC). La evaluación de la fuerza dinámica máxima (FDM) de extensión unilateral de la rodilla se realizó mediante la prueba de 1RM antes y después de la 6ª y 12ª semana de intervención. Para el análisis de los datos se realizó la prueba ANOVA de medidas repetidas con prueba de Bonferroni post hoc en el software SPSS (versión 21.0), considerando un nivel de significación de P < 0,05 en todos los análisis. Resultados: Las comparaciones antes de la intervención mostraron que los grupos AI y GC tenían menores valores de fuerza que ARFS y BIRFS (P < 0,05). El grupo ARFS presentó un aumento significativo de la FDM entre las semanas 1 y 6 (9%; P = 0,001) y entre las semanas 1 y 12 (21,6%; p = 0,008). El BIRFS tuvo un aumento de la FDM entre las semanas 1 y 6 (10,1%; p = 0,001), entre las semanas 1 y 12 (24,2%; p = 0,003) y las semanas 6 y 12 (12,8%; P = 0,030). El grupo AI tuvo una diferencia significativa entre las semanas 1 y 6 (38,7%; P < 0,001), entre las semanas 1 y 12 (62%, P < 0,001) y entre las semanas 6 y 12 (17,4%; p = 0,020), mientras que el GC no presentó diferencia entre los puntos del tiempo (P > 0,05). Conclusiones: ARFS y BIRFS aumentaron efectivamente la FDM en mujeres con osteoporosis.