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Low birth weight in response to salt restriction during pregnancy is not due to alterations in uterine-placental blood flow or the placental and peripheral renin-angiotensin system

LEANDRO, Sandra Marcia; FURUKAWA, Luzia Naoko Shinohara; SHIMIZU, Maria Heloisa Massola; CASARINI, Dulce Elena; SEGURO, Antonio Carlos; PATRIARCA, Giuliana; COELHO, Michella Soares; DOLNIKOFF, Miriam Sterman; HEIMANN, Joel Claudio
Fonte: PERGAMON-ELSEVIER SCIENCE LTD Publicador: PERGAMON-ELSEVIER SCIENCE LTD
Tipo: Artigo de Revista Científica
Português
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56.15%
A number of studies conducted in humans and in animals have observed that events occurring early in life are associated with the development of diseases in adulthood. Salt overload and restriction during pregnancy and lactation are responsible for functional (hemodynamic and hormonal) and structural alterations in adult offspring. Our group observed that lower birth weight and insulin resistance in adulthood is associated with salt restriction during pregnancy On the other hand, perinatal salt overload is associated with higher blood pressure and higher renal angiotensin II content in adult offspring. Therefore, we hypothesised that renin-angiotensin system (RAS) function is altered by changes in sodium intake during pregnancy. Such changes may influence fetoplacental blood flow and thereby fetal nutrient supply, with effects on growth in utero and, consequently, on birth weight. Female Wistar rats were fed low-salt (LS), normal-salt (NS), or high-salt (HS) diet, starting before conception and continuing until day 19 of pregnancy, Blood pressure, heart rate, fetuses and dams` body weight, placentae weight and litter size were measured on day 19 of pregnancy. Cardiac output, uterine and placental blood flow were also determined on day 19. Expressions of renin-angiotensin system components and of the TNF-alpha gene were evaluated in the placentae. Plasma renin activity (PRA) and plasma and tissue angiotensin-converting enzyme (ACE) activity...

Strength Training with Blood Flow Restriction Diminishes Myostatin Gene Expression

Laurentino, Gilberto Candido; Ugrinowitsch, Carlos; Silva, Hamilton Augusto Roschel da; Aoki, Marcelo Saldanha; Soares, Antonio Garcia; Neves, Manoel, Jr.; Aihara, Andre Yui; Correa Fernandes, Artur Da Rocha; Tricoli, Valmor
Fonte: Lippincott Williams & Wilkins; Philadelphia Publicador: Lippincott Williams & Wilkins; Philadelphia
Tipo: Artigo de Revista Científica
Português
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66.08%
LAURENTINO, G. C., C. UGRINOWITSCH, H. ROSCHEL, M. S. AOKI, A. G. SOARES, M. NEVES JR, A. Y. AIHARA, A. DA ROCHA CORREA FERNANDES, and V. TRICOLI. Strength Training with Blood Flow Restriction Diminishes Myostatin Gene Expression. Med. Sci. Sports Exerc., Vol. 44, No. 3, pp. 406-412, 2012. Purpose: The aim of the study was to determine whether the similar muscle strength and hypertrophy responses observed after either low-intensity resistance exercise associated with moderate blood flow restriction or high-intensity resistance exercise are associated with similar changes in messenger RNA (mRNA) expression of selected genes involved in myostatin (MSTN) signaling. Methods: Twenty-nine physically active male subjects were divided into three groups: low-intensity (20% one-repetition maximum (1RM)) resistance training (LI) (n = 10), low-intensity resistance exercise associated with moderate blood flow restriction (LIR) (n = 10), and high-intensity (80% 1RM) resistance exercise (HI) (n = 9). All of the groups underwent an 8-wk training program. Maximal dynamic knee extension strength (1RM), quadriceps cross-sectional area (CSA), MSTN, follistatin-like related genes (follistatin (FLST), follistatin-like 3 (FLST-3)), activin IIb, growth and differentiation factor-associated serum protein 1 (GASP-1)...

Safety and possible effects of low-intensity resistance training associated with partial blood flow restriction in polymyositis and dermatomyositis

Mattar, Melina A; Gualano, Bruno; Perandini, Luiz A; Shinjo, Samuel K; Lima, Fernanda R; Sá-Pinto, Ana L; Roschel, Hamilton
Fonte: Biblioteca Digital da Produção Intelectual da USP Publicador: Biblioteca Digital da Produção Intelectual da USP
Tipo: Artigo de Revista Científica
Português
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Abstract Introduction Our aim was to evaluate the safety and efficacy of a low-intensity resistance training program combined with partial blow flow restriction (BFR training) in a cohort of patients with polymyositis (PM) and dermatomyositis (DM). Methods In total, 13 patients with PM and DM completed a 12-week twice a week low-intensity (that is, 30% one-repetition-maximum (1RM)) resistance exercise training program combined with partial blood flow restriction (BFR). Assessments of muscle strength, physical function, quadriceps cross sectional (CSA) area, health-related quality of life, and clinical and laboratory parameters were assessed at baseline and after the intervention. Results The BFR training program was effective in increasing the maximal dynamic strength in both the leg-press (19.6%, P <0.001) and knee-extension exercises (25.2% P <0.001), as well as in the timed-stands (15.1%, P <0.001) and timed-up-and-go test (−4.5%, P =0.002). Quadriceps CSA was also significantly increased after the intervention (4.57%, P =0.01). Similarly, all of the components of the Short Form-36 Health Survey...

Safety and possible effects of low-intensity resistance training associated with partial blood flow restriction in polymyositis and dermatomyositis

Mattar, Melina A; Gualano, Bruno; Perandini, Luiz A; Shinjo, Samuel K; Lima, Fernanda R; Sá-Pinto, Ana L; Roschel, Hamilton
Fonte: Biblioteca Digital da Produção Intelectual da USP Publicador: Biblioteca Digital da Produção Intelectual da USP
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
66.06%
Abstract Introduction Our aim was to evaluate the safety and efficacy of a low-intensity resistance training program combined with partial blow flow restriction (BFR training) in a cohort of patients with polymyositis (PM) and dermatomyositis (DM). Methods In total, 13 patients with PM and DM completed a 12-week twice a week low-intensity (that is, 30% one-repetition-maximum (1RM)) resistance exercise training program combined with partial blood flow restriction (BFR). Assessments of muscle strength, physical function, quadriceps cross sectional (CSA) area, health-related quality of life, and clinical and laboratory parameters were assessed at baseline and after the intervention. Results The BFR training program was effective in increasing the maximal dynamic strength in both the leg-press (19.6%, P <0.001) and knee-extension exercises (25.2% P <0.001), as well as in the timed-stands (15.1%, P <0.001) and timed-up-and-go test (−4.5%, P =0.002). Quadriceps CSA was also significantly increased after the intervention (4.57%, P =0.01). Similarly, all of the components of the Short Form-36 Health Survey...

Efeitos do treinamento de força de baixa intensidade associado à restrição parcial do fluxo sanguíneo na força, hipertrofia e modulação das células satélites musculares em idosos; Effects of low load resistance training with partial blood flow restriction in the strength and hypertrophy gains as well as in the muscle satellite cells content in elderly

Vechin, Felipe Cassaro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 15/12/2014 Português
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O treinamento de força de baixa intensidade com restrição parcial do fluxo sanguíneo (TFR) emergiu como uma alternativa ao treinamento de força tradicional, com intensidades variando entre moderada a alta, principalmente para idosos que possam apresentar alguma limitação ou dificuldade na realização do treinamento mais intenso. Assim, o presente estudo objetivou analisar a efetividade do TFR na modulação dos níveis de força, área de secção transversa muscular (ASTM) e dos diferentes tipos de fibra (ASTF) bem como da quantidade de células satélites (CS) e mionúcleos (MIO) presentes nas células musculares de indivíduos idosos e comparar os ganhos proporcionados por esse treinamento com os ganhos do treinamento de força tradicional. Trinta sujeitos foram alocados de maneira aleatória e balanceada, pela área de secção transversa muscular do quadríceps, nos seguintes grupos: grupo controle (GC), treinamento de força de baixa intensidade com restrição parcial do fluxo sanguíneo (TFR) e treinamento de força de alta intensidade (TFAI). Após 12 semanas de treinamento, realizados duas vezes na semana, com o exercício Leg Press ambos os grupos, TFR e TFAI apresentaram aumentos nos níveis de força muscular (17% P = 0...

Respostas agudas da variabilidade da frequência cardíaca após sesão de exercício de força com restrição de fluxo sanguíneo = : Acute responses of heart rate variabiblity afer blood flow restriction resistance exercise; Acute responses of heart rate variabiblity afer blood flow restriction resistance exercise

Luciana Cristina de Souza
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 13/06/2013 Português
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A redução da Variabilidade da Frequência Cardíaca (VFC) está associada com o alto risco de eventos cardiovasculares, e também ao processo de envelhecimento e ao grau de sedentarismo. A prática regular de exercícios físicos, destacadamente os aeróbios, reflete em um aumento da VFC, decorrente da reduzida atividade simpática quase sempre acompanhada do aumento da atividade parassimpática sobre o coração, tanto em condições de repouso, como após sessão de treinamento. A prescrição do treinamento de força no envelhecimento tem sido prescrito por gerar ganhos de força e hipertrofia diminuindo o risco de lesões e quedas. Nesse sentido, o exercício resistido (RE) associado com uma restrição do fluxo sanguíneo (RE-BFR) tem sido utilizado por proporcionar ganhos de força ou hipertrofia muscular similar ao treinamento tradicional, fazendo uso de intensidades reduzidas de treinamento. Entretanto, pouco se sabe sobre as respostas autonômicas cardiovasculares agudas associadas a este tipo de treinamento. Objetivo: Desta forma, o presente estudo se propôs a comparar as respostas agudas da VFC após sessões de RE tradicional e RE-BFR, utilizando um ou dois exercícios em membros inferiores. Métodos: Quinze homens (47...

Four weeks of blood flow restricted training increases time to exhaustion at severe intensity cycling exercise

Corvino,Rogério Bulhões; Oliveira,Mariana Fernandes Mendes de; Santos,Rafael Penteado dos; Denadai,Benedito Sérgio; Caputo,Fabrizio
Fonte: Universidade Federal de Santa Catarina Publicador: Universidade Federal de Santa Catarina
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2014 Português
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The present study aimed to verify the effects of 4 weeks of low-intensity blood flow restricted (BFR) training on time to exhaustion (Tlim) at severe-intensity exercise. Thirteen physically active subjects (23 ± 3.4 years; 70.6 ± 7.8 kg; 170.9 ± 10 cm) were assigned to one of two groups: low-intensity interval training with (BFR, n=9) or without (CON, n=4) blood flow restricted. The interval training sessions consisted of 2 sets of 5-8 × 2-min intervals at 30% of peak power output (Ppeak) obtained during incremental exercise for LOW and BFR, separated by 1min of rest. For BFR a cuff was inflated (140-200mmHg) during the exercise bouts and deflated during rest intervals. The pressure was increased 20mmHg after three completed sessions, thus, in the last week the pressure applied was 200mmHg. Before and after 4 weeks intervention period, all subjects completed an incremental exercise until exhaustion and one-step transition to a severe-intensity work rate (110%Ppeak). The results revealed that BFR (Pre: 227 ± 44s vs. Post: 338 ± 76s), but not CON (Pre: 236 ± 24s vs. Post: 212 ± 26s), increase significantly Tlim at 110%Ppeak. It can be concluded that 4 weeks of BFR training, but not CON, increased the exercise tolerance at severe intensity domain. Therefore...

Blood flow restriction exercise stimulates mTORC1 signaling and muscle protein synthesis in older men

Fry, Christopher S.; Glynn, Erin L.; Drummond, Micah J.; Timmerman, Kyle L.; Fujita, Satoshi; Abe, Takashi; Dhanani, Shaheen; Volpi, Elena; Rasmussen, Blake B.
Fonte: American Physiological Society Publicador: American Physiological Society
Tipo: Artigo de Revista Científica
Português
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65.88%
The loss of skeletal muscle mass during aging, sarcopenia, increases the risk for falls and dependence. Resistance exercise (RE) is an effective rehabilitation technique that can improve muscle mass and strength; however, older individuals are resistant to the stimulation of muscle protein synthesis (MPS) with traditional high-intensity RE. Recently, a novel rehabilitation exercise method, low-intensity RE, combined with blood flow restriction (BFR), has been shown to stimulate mammalian target of rapamycin complex 1 (mTORC1) signaling and MPS in young men. We hypothesized that low-intensity RE with BFR would be able to activate mTORC1 signaling and stimulate MPS in older men. We measured MPS and mTORC1-associated signaling proteins in seven older men (age 70 ± 2 yr) before and after exercise. Subjects were studied identically on two occasions: during BFR exercise [bilateral leg extension exercise at 20% of 1-repetition maximum (1-RM) with pressure cuff placed proximally on both thighs and inflated at 200 mmHg] and during exercise without the pressure cuff (Ctrl). MPS and phosphorylation of signaling proteins were determined on successive muscle biopsies by stable isotopic techniques and immunoblotting, respectively. MPS increased 56% from baseline after BFR exercise (P < 0.05)...

Reactive hyperemia is not responsible for stimulating muscle protein synthesis following blood flow restriction exercise

Gundermann, David M.; Fry, Christopher S.; Dickinson, Jared M.; Walker, Dillon K.; Timmerman, Kyle L.; Drummond, Micah J.; Volpi, Elena; Rasmussen, Blake B.
Fonte: American Physiological Society Publicador: American Physiological Society
Tipo: Artigo de Revista Científica
Português
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65.88%
Blood flow restriction (BFR) to contracting skeletal muscle during low-intensity resistance exercise training increases muscle strength and size in humans. However, the mechanism(s) underlying these effects are largely unknown. We have previously shown that mammalian target of rapamycin complex 1 (mTORC1) signaling and muscle protein synthesis (MPS) are stimulated following an acute bout of BFR exercise. The purpose of this study was to test the hypothesis that reactive hyperemia is the mechanism responsible for stimulating mTORC1 signaling and MPS following BFR exercise. Six young men (24 ± 2 yr) were used in a randomized crossover study consisting of two exercise trials: low-intensity resistance exercise with BFR (BFR trial) and low-intensity resistance exercise with sodium nitroprusside (SNP), a pharmacological vasodilator infusion into the femoral artery immediately after exercise to simulate the reactive hyperemia response after BFR exercise (SNP trial). Postexercise mixed-muscle fractional synthetic rate from the vastus lateralis increased by 49% in the BFR trial (P < 0.05) with no change in the SNP trial (P > 0.05). BFR exercise increased the phosphorylation of mTOR, S6 kinase 1, ribosomal protein S6, ERK1/2, and Mnk1-interacting kinase 1 (P < 0.05) with no changes in mTORC1 signaling in the SNP trial (P > 0.05). We conclude that reactive hyperemia is not a primary mechanism for BFR exercise-induced mTORC1 signaling and MPS. Further research is necessary to elucidate the cellular mechanism(s) responsible for the increase in mTOR signaling...

Proliferation of myogenic stem cells in human skeletal muscle in response to low-load resistance training with blood flow restriction

Nielsen, Jakob Lindberg; Aagaard, Per; Bech, Rune Dueholm; Nygaard, Tobias; Hvid, Lars Grøndahl; Wernbom, Mathias; Suetta, Charlotte; Frandsen, Ulrik
Fonte: Blackwell Science Inc Publicador: Blackwell Science Inc
Tipo: Artigo de Revista Científica
Português
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66.08%
Low-load resistance training with blood flow restriction has been shown to elicit substantial increases in muscle mass and muscle strength; however, the effect on myogenic stem cells (MSCs) and myonuclei number remains unexplored. Ten male subjects (22.8 ± 2.3 years) performed four sets of knee extensor exercise (20% 1RM) to concentric failure during blood flow restriction (BFR) of the proximal thigh (100 mmHg), while eight work-matched controls (21.9 ± 3.0 years) trained without BFR (control, CON). Twenty-three training sessions were performed within 19 days. Maximal isometric knee extensor strength (MVC) was examined pre- and post-training, while muscle biopsies were obtained at baseline (Pre), after 8 days intervention (Mid8) and 3 (Post3) and 10 days (Post10) post training to examine changes in myofibre area (MFA), MSC and myonuclei number. MVC increased by 7.1% (Post5) and 10.6% (Post12) (P < 0.001) with BFR training, while type I and II MFA increased by 38% (Mid8), 35–37% (Post3) and 31–32% (Post10) (P < 0.001). MSCs per myofibre increased with BFR training from 0.10 ± 0.01 (Pre) to 0.38 ± 0.02 (Mid8), 0.36 ± 0.04 (Post3) and 0.25 ± 0.02 (Post10) (P < 0.001). Likewise, myonuclei per myofibre increased from 2.49 ± 0.07 (Pre) to 3.30 ± 0.22 (Mid8)...

Effect of multiple set on intramuscular metabolic stress during low-intensity resistance exercise with blood flow restriction

Suga, Tadashi; Okita, Koichi; Takada, Shingo; Omokawa, Masashi; Kadoguchi, Tomoyasu; Yokota, Takashi; Hirabayashi, Kagami; Takahashi, Masashige; Morita, Noriteru; Horiuchi, Masahiro; Kinugawa, Shintaro; Tsutsui, Hiroyuki
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: Artigo de Revista Científica
Português
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65.88%
Our previous study reported that intramuscular metabolic stress during low-intensity resistance exercise was significantly enhanced by combining blood flow restriction (BFR); however, they did not reach the levels achieved during high-intensity resistance exercise. That study was performed using a single set of exercise; however, usual resistance exercise consists of multiple sets with rest intervals. Therefore, we investigated the intramuscular metabolic stress during multiple-set BFR exercises, and compared the results with those during multiple-set high-intensity resistance exercise. Twelve healthy young subjects performed 3 sets of 1-min unilateral plantar flexion (30 repetitions) with 1-min intervals under 4 different conditions: low intensity (L, 20 % 1 RM) and high intensity (H, 65 % 1 RM) without BFR, and L with intermittent BFR (IBFR, only during exercise) and with continuous BFR (CBFR, during rest intervals as well as exercise). Intramuscular metabolic stress, defined as intramuscular metabolites and pH, and muscle fiber recruitment were evaluated by 31P-magnetic resonance spectroscopy. The changes of intramuscular metabolites and pH during IBFR were significantly greater than those in L but significantly lower than those in H. By contrast...

Legs and Trunk Muscle Hypertrophy Following Walk Training with Restricted Leg Muscle Blood Flow

Sakamaki, Mikako; G. Bemben, Michael; Abe, Takashi
Fonte: Asist Group Publicador: Asist Group
Tipo: Artigo de Revista Científica
Publicado em 01/06/2011 Português
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We examined the effect of walk training combined with blood flow restriction (BFR) on the size of blood flow-restricted distal muscles, as well as, on the size of non-restricted muscles in the proximal limb and trunk. Nine men performed walk training with BFR and 8 men performed walk training alone. Training was conducted two times a day, 6 days/wk, for 3 wk using five sets of 2-min bouts (treadmill speed at 50 m/min), with a 1-min rest between bouts. After walk training with BFR, MRI-measured upper (3.8%, P < 0.05) and lower leg (3.2%, P < 0. 05) muscle volume increased significantly, whereas the muscle volume of the gluteus maximus (-0.6%) and iliopsoas (1.8%) and the muscle CSA of the lumber L4-L5 (-1.0) did not change. There was no significant change in muscle volume in the walk training alone. Our results suggest that the combination of leg muscle blood flow restriction with slow walk training elicits hypertrophy only in the distal blood flow restricted leg muscles. Exercise intensity may be too low during BFR walk training to increase muscle mass in the non- blood flow restricted muscles (gluteus maximus and other trunk muscles).

Effects of low-intensity concentric and eccentric exercise combined with blood flow restriction on indices of exercise-induced muscle damage

Thiebaud, Robert S.; Yasuda, Tomohiro; Loenneke, Jeremy P.; Abe, Takashi
Fonte: Akadémiai Kiadó Publicador: Akadémiai Kiadó
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
65.88%
Low-intensity blood-flow restriction (BFR) resistance training significantly increases strength and muscle size, but some studies report it produces exercise-induced muscle damage (EIMD) in the lower body after exercise to failure.

Effects of High-Intensity Blood Flow Restriction Exercise on Muscle Fatigue

Neto, Gabriel R.; Santos, Heleodório H.; Sousa, Juliana B. C.; Júnior, Adenilson T. A.; Araújo, Joamira P.; Aniceto, Rodrigo R.; Sousa, Maria S. C.
Fonte: Akademia Wychowania Fizycznego w Katowicach Publicador: Akademia Wychowania Fizycznego w Katowicach
Tipo: Artigo de Revista Científica
Publicado em 08/07/2014 Português
Relevância na Pesquisa
66.13%
Strength training combined with blood flow restriction (BFR) have been used to improve the levels of muscle adaptation. The aim of this paper was to investigate the acute effect of high intensity squats with and without blood flow restriction on muscular fatigue levels. Twelve athletes (aged 25.95 ± 0.84 years) were randomized into two groups: without Blood Flow Restriction (NFR, n = 6) and With Blood Flow Restriction (WFR, n = 6) that performed a series of free weight squats with 80% 1-RM until concentric failure. The strength of the quadriceps extensors was assessed in a maximum voluntary isometric contraction integrated to signals from the surface electromyogram. The average frequency showed significant reductions in the WFR group for the vastus lateralis and vastus medialis muscles, and intergroup only for the vastus medialis. In conclusion, a set of squats at high intensity with BFR could compromise muscle strength immediately after exercise, however, differences were not significant between groups.

Effects of cuff width on arterial occlusion: implications for blood flow restricted exercise

Loenneke, Jeremy P.; Fahs, Christopher A.; Rossow, Lindy M.; Sherk, Vanessa D.; Thiebaud, Robert S.; Abe, Takashi; Bemben, Debra A.; Bemben, Michael G.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
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56.11%
The purpose of this study was to determine the difference in cuff pressure which occludes arterial blood flow for two different types of cuffs which are commonly used in blood flow restriction (BFR) research. Another purpose of the study was to determine what factors (i.e., leg size, blood pressure, and limb composition) should be accounted for when prescribing the restriction cuff pressure for this technique. One hundred and sixteen (53 males, 63 females) subjects visited the laboratory for one session of testing. Mid-thigh muscle (mCSA) and fat (fCSA) cross-sectional area of the right thigh were assessed using peripheral quantitative computed tomography. Following the mid-thigh scan, measurements of leg circumference, ankle brachial index, and brachial blood pressure were obtained. Finally, in a randomized order, arterial occlusion pressure was determined using both narrow and wide restriction cuffs applied to the most proximal portion of each leg. Significant differences were observed between cuff type and arterial occlusion (narrow: 235 (42) mmHg vs. wide: 144 (17) mmHg; p = 0.001, Cohen’s D = 2.52). Thigh circumference or mCSA/fCSA with ankle blood pressure, and diastolic blood pressure, explained the most variance in the cuff pressure required to occlude arterial flow. Wide BFR cuffs restrict arterial blood flow at a lower pressure than narrow BFR cuffs...

The Acute Effect of Resistance Exercise with Blood Flow Restriction with Hemodynamic Variables on Hypertensive Subjects

Araújo, Joamira P.; Silva, Eliney D.; Silva, Julio C. G.; Souza, Thiago S. P.; Lima, Eloíse O.; Guerra, Ialuska; Sousa, Maria S. C.
Fonte: Akademia Wychowania Fizycznego w Katowicach Publicador: Akademia Wychowania Fizycznego w Katowicach
Tipo: Artigo de Revista Científica
Publicado em 12/11/2014 Português
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66.05%
The purpose of this study was to analyze systolic blood pressure (SBP), diastolic blood pressure (DBP) and the heart rate (HR) before, during and after training at moderate intensity (MI, 50%-1RM) and at low intensity with blood flow restriction (LIBFR). In a randomized controlled trial study, 14 subjects (average age 45±9,9 years) performed one of the exercise protocols during two separate visits to the laboratory. SBP, DBP and HR measurements were collected prior to the start of the set and 15, 30, 45 and 60 minutes after knee extension exercises. Repeated measures of analysis of variance (ANOVA) were used to identify significant variables (2 × 5; group × time). The results demonstrated a significant reduction in SBP in the LIBFR group. These results provide evidence that strength training performed acutely alters hemodynamic variables. However, training with blood flow restriction is more efficient in reducing blood pressure in hypertensive individuals than training with moderate intensity.

Low Intensity Resistance Exercise Training with Blood Flow Restriction: Insight into Cardiovascular Function, and Skeletal Muscle Hypertrophy in Humans

Park, Song-Young; Kwak, Yi Sub; Harveson, Andrew; Weavil, Joshua C; Seo, Kook E.
Fonte: The Korean Physiological Society and The Korean Society of Pharmacology Publicador: The Korean Physiological Society and The Korean Society of Pharmacology
Tipo: Artigo de Revista Científica
Português
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65.88%
Attenuated functional exercise capacity in elderly and diseased populations is a common problem, and stems primarily from physical inactivity. Decreased function and exercise capacity can be restored by maintaining muscular strength and mass, which are key factors in an independent and healthy life. Resistance exercise has been used to prevent muscle loss and improve muscular strength and mass. However, the intensities necessary for traditional resistance training to increase muscular strength and mass may be contraindicated for some at risk populations, such as diseased populations and the elderly. Therefore, an alternative exercise modality is required. Recently, blood flow restriction (BFR) with low intensity resistance exercise (LIRE) has been used for such special populations to improve their function and exercise capacity. Although BFR+LIRE has been intensively studied for a decade, a comprehensive review detailing the effects of BFR+LIRE on both skeletal muscle and vascular function is not available. Therefore, the purpose of this review is to discuss previous studies documenting the effects of BFR+LIRE on hormonal and transcriptional factors in muscle hypertrophy and vascular function, including changes in hemodynamics, and endothelial function.

Blood flow restriction prevents muscle damage but not protein synthesis signaling following eccentric contractions

Sudo, Mizuki; Ando, Soichi; Poole, David C; Kano, Yutaka
Fonte: John Wiley & Sons, Ltd Publicador: John Wiley & Sons, Ltd
Tipo: Artigo de Revista Científica
Publicado em 06/07/2015 Português
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65.88%
There is a growing body of evidence to suggest that resistance training exercise combined with blood flow restriction (BFR) increases muscle size and strength in humans. Eccentric contraction (ECC) frequently induces severe muscle damage. However, it is not known whether and to what extent muscle damage occurs following ECC + BFR due to the difficulty of conducting definitive invasive studies. The purpose of this study was to examine muscle fiber damage following ECC + BFR at the cellular level. High-intensity ECC was purposefully selected to maximize the opportunity for muscle damage and hypertrophic signaling in our novel in vivo animal model. Male Wistar rats were assigned randomly to the following groups: ECC and ECC + BFR at varying levels of occlusion pressure (140, 160, and 200 Torr). In all conditions, electrical stimulation was applied to the dorsiflexor muscles simultaneously with electromotor-induced plantar flexion. We observed severe histochemical muscle fiber damage (area of damaged fibers/total fiber area analyzed) following ECC (26.4 ± 4.0%). Surprisingly, however, muscle damage was negligible following ECC + BFR140 (2.6 ± 1.2%), ECC+BFR160 (3.0 ± 0.5%), and ECC + BFR200 (0.2 ± 0.1%). Ribosomal S6 kinase 1 (S6K1) phosphorylation...

The effects of bodyweight-based exercise with blood flow restriction on isokinetic knee muscular function and thigh circumference in college students

Kang, Dong Yeon; Kim, Hyoung Su; Lee, Kyung Soon; Kim, Young Mi
Fonte: The Society of Physical Therapy Science Publicador: The Society of Physical Therapy Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
66.17%
[Purpose] The purpose of this study was to investigate the effects of bodyweight-based exercise with blood flow restriction on isokinetic muscular function and thigh circumference in college students. [Subjects and Methods] The subjects were 17 college students who were recruited and randomly assigned to bodyweight-based exercise with blood flow restriction and bodyweight-based exercise groups. Participants performed front lunges and squats at ratings of perceived exertion of 11–13 three times a week during a 6-week training period. The peak torque/ body weight (%) of the knee flexor and extensor was measured using a HUMAC NORM System (Cybex 770-NORM®, Cybex International, Medway, MA, USA), and the circumference of the thigh was measured. PASW Statistics was used for data analysis. [Results] There were significant differences in the peak torque/ body weight (%) of the flexors in both thighs (at 180°/sec) after bodyweight-based exercise with blood flow restriction. In addition, the circumference changes in both thighs were significant after bodyweight-based exercise with blood flow restriction and between the two groups. [Conclusion] This study suggests that bodyweight-based exercise with blood flow restriction may be an effective method to improve the muscle power and hypertrophy of the lower extremity in a clinical setting.

Four weeks of blood flow restricted training increases time to exhaustion at severe intensity cycling exercise; Quatro semanas de treinamento com restrição de fluxo sanguíneo aumenta o tempo de exaustão em exercício severo no ciclismo

Corvino, Rogério Bulhões; State University of Santa Catarina; Oliveira, Mariana Fernandes Mendes de; State University of Santa Catarina. Federal University of Santa Catarina.; Santos, Rafael Penteado dos; State University of Santa Catarina; Denadai, Ben
Fonte: Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil Publicador: Universidade Federal de Santa Catarina. Florianópolis, SC. Brasil
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; "Avaliado por Pares",; Original paper; Avaliado por Pares; Artigos Originais Formato: application/pdf
Publicado em 01/08/2014 Português
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http://dx.doi.org/10.5007/1980-0037.2014v16n5p570 The present study aimed to verify the effects of 4 weeks of low-intensity blood flow restricted (BFR) training on time to exhaustion (Tlim) at severe-intensity exercise. Thirteen physically active subjects (23 ± 3.4 years; 70.6 ± 7.8 kg; 170.9 ± 10 cm) were assigned to one of two groups: low-intensity interval training with (BFR, n=9) or without (CON, n=4) blood flow restricted. The interval training sessions consisted of 2 sets of 5-8 × 2-min intervals at 30% of peak power output (Ppeak) obtained during incremental exercise for LOW and BFR, separated by 1min of rest. For BFR a cuff was inflated (140-200mmHg) during the exercise bouts and deflated during rest intervals. The pressure was increased 20mmHg after three completed sessions, thus, in the last week the pressure applied was 200mmHg. Before and after 4 weeks intervention period, all subjects completed an incremental exercise until exhaustion and one-step transition to a severe-intensity work rate (110%Ppeak). The results revealed that BFR (Pre: 227 ± 44s vs. Post: 338 ± 76s), but not CON (Pre: 236 ± 24s vs. Post: 212 ± 26s), increase significantly Tlim at 110%Ppeak. It can be concluded that 4 weeks of BFR training, but not CON...