The effects of blood flow restriction on the quadriceps femoris and knee stability after anterior cruciate ligament reconstruction / 中华物理医学与康复杂志

Objective:To explore the effect of blood flow restriction training on the quadriceps femoris and on knee stability after anterior cruciate ligament reconstruction.Methods:Forty patients recovering from anterior cruciate ligament reconstruction were randomly divided into an experimental group and a control group, each of 20. In addition to routine rehabilitation training, the control group was given routine knee flexion and extension strength training, while the experimental group trained for an additional 20 minutes doing knee flexion and extension resistance training with the blood pressure in their groins at 70% of their individual arterial occlusive pressure. (The mean pressure was (123±11.23)mmHg). The training lasted 8 weeks, three times a week. Knee function and hamstring and quadriceps peak torque were assessed before and after the intervention using a Lysholm scale and Humac Norm isokinetic muscle strength tests.Results:There were no significant differences between the two groups in any of the measurements before the training. After the intervention, all of the measurements had improved significantly in both groups, with the average Lysholm score, H/Q% and peak torque of the experimental group significantly better than the control group′s averages.Conclusions:Blood flow restriction training can improve the effectiveness of quadriceps femoris strength, knee stability and knee function training after anterior cruciate ligament reconstruction.

Blood flow restriction can improve knee proprioception and motor coordination after anterior cruciate ligament reconstruction / 中华物理医学与康复杂志

Objective:To explore any effect of blood flow restriction during exercise on knee proprioception and motor coordination after anterior cruciate ligament (ACL) reconstruction.Methods:Thirty patients recovering from ACL reconstruction were randomly divided into an experimental group and a control group, each of 15. Both groups were given routine rehabilitation training, while the experimental group was additionally provided with 45 minutes of training with blood flow restriction, 3 times a week for 8 weeks. The blood flow restriction training involved constant pressure in the groin while the patient performed knee flexion and extension resistance training, squats, alternate knee flexion and extension and ergometer cycling. Before and after the intervention, both groups′ knee function, proprioception and lower limb motor coordination were evaluated using the Lysholm knee scale, the Humac isokinetic measurement system and surface electromyography.Results:Before the experiment there were no significant differences between the two groups in any of the measurements. After the intervention, both groups′ average Lysholm score had improved significantly, and errors in reproducing a knee angle had decreased significantly. Significantly better improvement was observed in the observation group than in the control group. That group′s average coordinated contraction rate on the affected side in extension and flexion was also significantly better than the control group′s ave-rage. Indeed, there were no significant differences in the contraction rates between the healthy and affected sides.Conclusions:Training with restricted blood flow can significantly improve knee function, proprioception and motor coordination after anterior cruciate ligament reconstruction.

Blood flow restriction therapy applied to sports training / Terapia de restrição do fluxo sanguíneo aplicada ao treinamento esportivo / Terapia de restricción del flujo sanguíneo aplicada al entrenamiento deportivo

ABSTRACT Introduction: Blood flow restriction therapy, also known as KAATSU pressurization training or ischemic exercise training is a controlled method of vascular occlusion combined with resistance training, with the great growth of its research in recent years. Regular strength training, prevention of lean mass loss, and post-operative rehabilitation are some areas in which the therapy has been prominent. It is believed that it can also be beneficial in sports performance. Objective: Study the effects of an intervention with blood flow restriction therapy on athletes during training. Methods: 32 college athletes with more than two years of experience in sports training, free of injuries, and 20±3 years old were volunteers. They were randomly divided into groups A (no pressure), B (training pressure), C (intermittent pressure), D (full compression). Results: The athletes in the no pressurization group, intermittent pressurization group, training pressurization group, and full-time pressurization group showed significant differences (P<0.05). It can be considered that there is a significant difference in the muscular endurance indexes of the athletes in the non-compression group before and after training, while the athletes in the non-compression group achieved a significant increase in muscular endurance after 6 weeks of training Conclusion: Blood flow restriction therapy can effectively enhance the training effect with various strength qualities, and play a role as a promoter of hypertrophy and vascularization. Level of evidence II; Therapeutic studies - investigation of treatment outcomes.

RESUMO Introdução: A terapia de restrição do fluxo sanguíneo, também conhecida como treinamento de pressurização da KAATSU ou treinamento de exercício isquêmico é um método controlado de oclusão vascular combinado ao treino de resistência, com grande crescimento de suas pesquisas nos últimos anos. Treinos regulares de força, prevenção de perda de massa magra e reabilitação pós-operatória são algumas áreas em que a terapia tem se destacado. Acredita-se que possa ser benéfica também no desempenho esportivo. Objetivo: Estudar os efeitos de uma intervenção com terapia de restrição do fluxo sanguíneo nos atletas durante o treinamento. Métodos: Foram voluntários 32 atletas universitários com mais de dois anos de experiência em treinamento esportivo, livres de lesões e com 20±3 anos de idade. Foram divididos aleatoriamente em grupos A (sem pressão), B (pressão de treinamento), C (pressão intermitente), D (compressão integral). Resultados: Os atletas do grupo sem pressurização, do grupo de pressurização intermitente, do grupo de pressurização de treinamento e do grupo de pressurização em tempo integral, mostraram diferenças significativas (P<0,05). Pode-se considerar que existe uma diferença significativa nos índices de resistência muscular dos atletas do grupo sem compressão antes e depois do treinamento, enquanto os atletas do grupo sem compressão conseguiram um aumento significativo na resistência muscular após 6 semanas de treinamento Conclusão: A terapia de restrição do fluxo sanguíneo pode efetivamente melhorar o efeito de treinamento com várias qualidades de força, além de desempenhar um papel como promotor de hipertrofia e vascularização. Nível de evidência II; Estudos terapêuticos - investigação dos resultados do tratamento.

RESUMEN Introducción: La terapia de restricción del flujo sanguíneo, también conocida como entrenamiento de presurización KAATSU o entrenamiento de ejercicio isquémico es un método controlado de oclusión vascular combinado con entrenamiento de resistencia, con gran crecimiento de su investigación en los últimos años. El entrenamiento regular de la fuerza, la prevención de la pérdida de masa magra y la rehabilitación postoperatoria son algunas de las áreas en las que la terapia se ha destacado. Se cree que también puede ser beneficioso para el rendimiento deportivo. Objetivo: Estudiar los efectos de una intervención con terapia de restricción del flujo sanguíneo en atletas durante el entrenamiento. Métodos: 32 atletas universitarios con más de dos años de experiencia en el entrenamiento deportivo, libres de lesiones y con 20±3 años de edad fueron voluntarios. Se dividieron aleatoriamente en los grupos A (sin presión), B (presión de entrenamiento), C (presión intermitente), D (compresión total). Resultados: Los atletas del grupo sin presurización, del grupo con presurización intermitente, del grupo con presurización de entrenamiento y del grupo con presurización a tiempo completo mostraron diferencias significativas (P<0,05). Se puede considerar que existe una diferencia significativa en los índices de resistencia muscular de los atletas del grupo sin compresión antes y después del entrenamiento, mientras que los atletas del grupo sin compresión lograron un aumento significativo de la resistencia muscular después de 6 semanas de entrenamiento Conclusión: La terapia de restricción del flujo sanguíneo puede mejorar eficazmente el efecto del entrenamiento con diversas cualidades de fuerza, y desempeñar un papel como promotor de la hipertrofia y la vascularización. Nivel de evidencia II; Estudios terapéuticos - investigación de los resultados del tratamiento.

Effect of exercise under blood flow restriction on risk of fragility fractures in postmenopausal patients with chronic obstructive pulmonary disease / 中国康复理论与实践

ObjectiveTo explore the effect of blood flow restriction (BFR)-based aerobic exercise and low-intensity resistance program on bone strength, hormone secretion, lung function and exercise capacity in postmenopausal patients with chronic obstructive pulmonary disease (COPD), to relieve the risk of fragility fractures and mortality. MethodsFrom June, 2020 to January, 2021, 67 postmenopausal patients with COPD were selected from seven community hospitals such as Chongqing Yuxi Hospital, etc. The patients were randomly divided into control group (n = 33) and experimental group (n = 34). Both groups received conventional treatment and implemented a pulmonary rehabilitation program consisting of aerobic exercise and low-intensity resistance, while the experimental group finished the low-intensity resistance under BFR, for 24 weeks. Before and after intervention, the femoral neck bone mineral density (BMD) was measured with dual-energy X-ray; the interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), 25-hydroxyvitamin D3 [25(OH)D3], estradiol (E2), bone-specific alkaline phosphatase (BALP), tartrate-resistant acid phosphatase (TRACP), osteocalcin (BGP), β-I collagen cross-linked C-terminal peptide (β-CTX), growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels were measured with ELISA; the forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) were measured with lung function test; the maximum oxygen uptake (VO2max) and anaerobic threshold (AT) were measured with cardiopulmonary exercise test; the body mass index (BMI) and muscle mass were measured with bioelectrical impedance; the peak torque of knee flexion and extension, and fatigue index were measured with isokinetic muscle strength test; and they were also assessed with distance of 6-minute walk test (6MWT), modified Falls Efficacy Scale (MFES), Timed Up and Go Test (TUGT), and Tinetti Performance Oriented Mobility Assessment (Tinetti). ResultsFour cases dropped down in the control group, and five in the experimental group. All the indexes improved in the experimental group after intervention (|t| > 2.208, P < 0.05), and most of the indexes improved in the control group (|t| > 2.052, P < 0.05); while the E2, GH, IGF-1, IL-6, TNF-α, TRACP, β-CTX, BALP, FEV1, AT, distance of 6MWT, muscle mass, peak torque of knee flexion and extension, fatigue index, time of TUGT, and scores of Tinetti and MFES were better in the experimental group than in the control group (|t| > 2.141, P < 0.05). ConclusionExercise under BFR may improve the bone strength, lung function, estrogen secretion and exercise ability of postmenopausal patients with COPD, which may help to relieve the risk of fragility fractures.

Effects of blood flow restriction in large and small muscle groups / Efeitos da restrição do fluxo sanguíneo em grupamentos musculares grandes e pequenos / Efectos de la restricción del flujo sanguíneo en grupos musculares grandes y pequeños

ABSTRACT Introduction It is known that strength training brings improvements in health and sports performance by causing muscle hypertrophy and increased strength, as well as modifying some hemodynamic and physiological factors. Several strength training methodologies have been developed, one of which is vascular occlusion. There are few studies with large muscle groups due to poor adherence to the training style and the fact that vascular occlusion of large muscle groups is more difficult. Objective To verify and compare the hemodynamic effects of exercise with and without vascular occlusion in different muscle groups. Methods Quantitative crossover study, with cross-sectional and field procedures. The sample consisted of 10 physically active healthy male and female subjects between 18 and 30 years of age. With the cross-over design, all the volunteers participated in 3 groups: intervention with vascular occlusion, intervention without vascular occlusion and the control group. Results Overall, lactate and cholesterol remained elevated after 15 minutes of recovery and blood glucose and blood pressure did not vary among the groups. Conclusion Vascular occlusion training is an effective method for manipulating hemodynamic variables. Evidence level II; Clinical study.

RESUMO Introdução Sabe-se que o treino de força traz melhorias para a saúde e o desempenho esportivo, por ocasionar hipertrofia muscular e aumento de força, além de modificar alguns fatores hemodinâmicos e fisiológicos. Foram desenvolvidos vários métodos de treinamento de força, entre eles, a oclusão vascular. Porém, existem poucos estudos com grandes grupamentos musculares, devido à pouca adesão ao estilo de treino e ao fato de a oclusão vascular de grandes grupos musculares ser mais difícil. Objetivo Verificar e comparar os efeitos hemodinâmicos do exercício com e sem oclusão vascular em diferentes grupamentos musculares. Métodos Estudo quantitativo, cruzado, com procedimentos transversais e de campo. A amostra foi composta por 10 indivíduos saudáveis e fisicamente ativos do sexo masculino e feminino, na faixa etária de 18 a 30 anos. Com o desenho cruzado, todos os voluntários participaram de 3 grupos: intervenção com oclusão vascular, intervenção sem oclusão vascular e grupo controle. Resultados De forma geral, entre grupos, o lactato e o colesterol se mantiveram elevados depois de 15 minutos de recuperação, a glicemia e as pressões arteriais não variaram. Conclusão O treinamento com oclusão vascular é um método eficaz para manipular as variáveis hemodinâmicas. Nível de evidência II; Estudo clínico.

RESUMEN Introducción Se sabe que el entrenamiento de fuerza trae mejoras para la salud y el desempeño deportivo, por causar hipertrofia muscular y aumento de fuerza, además de modificar algunos factores hemodinámicos y fisiológicos. Fueron desarrollados varios métodos de entrenamiento de fuerza, entre ellos, la oclusión vascular. Sin embargo, existen pocos estudios con grandes grupos musculares, debido a la poca adhesión al estilo de entrenamiento y al hecho de que la oclusión vascular de grandes grupos musculares grandes es más difícil. Objetivo Verificar y comparar los efectos hemodinámicos del ejercicio con y sin oclusión vascular en diferentes grupos musculares. Métodos Estudio cuantitativo, cruzado, con procedimientos transversales y de campo. La muestra fue compuesta por 10 individuos saludables y físicamente activos del sexo masculino y femenino, en el grupo de edad de 18 a 30 años. Con el diseño cruzado, todos los voluntarios participaron en 3 grupos: intervención con oclusión vascular, intervención sin oclusión vascular y grupo control. Resultados De forma general, entre los grupos, el lactato y el colesterol se mantuvieron elevados después de 15 minutos de recuperación, la glucemia y las presiones arteriales no variaron. Conclusión El entrenamiento de oclusión vascular es un método eficaz para manipular las variables hemodinámicas. Nivel de evidencia II; Estudio clínico.

Physiological Effects of Strength Training Incorporating Blood Flow Restriction Underwater / 日本温泉気候物理医学会雑誌

  Strength training performed while restricting blood flow is believed to cause the secretion of growth hormones under low load intensities and allow for muscle hypertrophy and increased muscle strength. This has potential clinical applications for elderly individuals and people with existing conditions. However, previous research has been performed on land, with hemodynamics and growth hormone secretion trends for training performed underwater unclear. Against this background, we investigated the effects of blood flow restriction training underwater on hemodynamics and plasma growth hormone (GH) levels. Twelve healthy university students were divided into two groups: a localized immersion group where only the upper limb of the dominant hand was submerged, and a whole-body immersion group where participants were submerged to the xiphoid process. Immersed according to respective group protocols, both groups performed flexion and extension of the shoulder joint for 10 minutes with a pressurized cuff at the base of the upper arm under both 0 mmHg and 50 mmHg cuff pressures. Measured hemodynamics were heart rate, systolic blood pressure, and diastolic blood pressure. Plasma GH levels were measured from blood samples. This study revealed that underwater blood flow restriction strength training induced plasma GH level secretion under 50 mmHg conditions. In addition, high levels of GH secretion were shown in the localized immersion group for strength training even when the cuff was not pressurized. Conversely, no significant differences were evident in any measured hemodynamic categories. Results suggest that, in addition to cuff pressure, blood flow restriction training is affected by the body part immersed in water.

Blood flow restriction training can enhance the lower limb joint functioning of persons with rheumatoid arthritis / 中华物理医学与康复杂志

Objective:To investigate the effect of blood flow restriction training (BFRT) on the rehabilitation of lower limb joint function in persons with rheumatoid arthritis (RA).Methods:Sixty RA patients were randomly divided into an observation group and a control group, each of 30. Both groups were given conventional slow-acting anti-rheumatic medication with low-dose glucocorticoids. Everyone received basic exercise training including joint training and plyometric training, but the observation group additionally received BFRT training during which constant pressure in an inguinal cuff restricted blood flow to the lower limbs. The observation group′s training program also included double leg push-ups and double knee extensions. Before, and 12 weeks after the intervention, the joint symptoms were assessed using swollen joint counts out of 28 joints (SJC28), tender joint counts out of 28 joints (TJC28) and pain reported using a visual analogue scale (VAS). Lower limb motor functioning was assessed using a timed-stands test (TST) and the timed-up-and-go (TUG) test. Life quality was evaluated using a health assessment questionnaire (HAQ) and arthritis self-efficacy scale-8 (ASES-8). Disease activity was quantified using a clinical disease activity index (CDAI), a simplified disease activity index (SDAI) and disease activity scoring with a 28-joint count (DAS28).Results:There were no significant differences between the two groups before the intervention. After the intervention all of the indicators except the DAS28 had improved significantly in the observation group. At that point they were also all better than the control group′s averages, where no significant improvement was observed. No serious adverse events occurred in either group during the experiment.Conclusions:BFRT can safely relieve joint symptoms and improve the lower limb motor functioning and life quality of RA sufferers. It is worthy of further clinical research and promotion.

Effects of Short-term Lower Extremity Blood Flow Restriction Based on Limb Linkage Training on Endurance of Cardiopulmonary Endurance, Lower Extremity Muscle Endurance and Balance Function of Healthy Young People / 中国康复理论与实践

Objective To observe the effects of short-term blood flow restriction (BFR) based on limb linkage training on cardiopulmonary endurance, lower limb muscle endurance and balance function of healthy people. Methods From December, 2019 to March, 2020, 20 healthy young people were randomly divided into control group (n = 10) and experimental group (n = 10). They accepted limb linkage training with the loading of anaerobic threshold (AT) according to the results of cardiopulmonary exercise test (CPET), 20 minutes a time, three times a week, for two weeks; while the experimental group wore 250 mmHg blood pressure training belt at the root of both thighs; the control group wore blood pressure training belt with no pressure. They were assessed with CPET, 6-minute walking test, wall squatting, seat test and functional reach test before and after training. Results After training, all the indexes improved in both groups (|t| > 2.321, P < 0.05), except functional reach test, the results of wall squatting and seat test were better in the experimental group than in the control group (t > 2.660, P < 0.05). Conclusion Limb linkage training combined with lower extremity BFR could further improve lower limb muscle endurance.

Effects of Short-term Lower Extremity Blood Flow Restriction Based on Limb Linkage Training on Endurance of Cardiopulmonary Endurance, Lower Extremity Muscle Endurance and Balance Function of Healthy Young People / 中国康复理论与实践

Objective To observe the effects of short-term blood flow restriction (BFR) based on limb linkage training on cardiopulmonary endurance, lower limb muscle endurance and balance function of healthy people. Methods From December, 2019 to March, 2020, 20 healthy young people were randomly divided into control group (n = 10) and experimental group (n = 10). They accepted limb linkage training with the loading of anaerobic threshold (AT) according to the results of cardiopulmonary exercise test (CPET), 20 minutes a time, three times a week, for two weeks; while the experimental group wore 250 mmHg blood pressure training belt at the root of both thighs; the control group wore blood pressure training belt with no pressure. They were assessed with CPET, 6-minute walking test, wall squatting, seat test and functional reach test before and after training. Results After training, all the indexes improved in both groups (|t| > 2.321, P < 0.05), except functional reach test, the results of wall squatting and seat test were better in the experimental group than in the control group (t > 2.660, P < 0.05). Conclusion Limb linkage training combined with lower extremity BFR could further improve lower limb muscle endurance.

Efeito do treino com restrição de fluxo sanguíneo versus treino resistido de alta intensidade sobre a força de indivíduos sedentários: um ensaio clínico controlado e randomizado / Blood flow restriction training versus high-intensity resistance training in sedentary individuals: a randomized controlled trial

Objetivos: comparar os efeitos do treino com restrição de flux o sanguíneo com o treino resistido de alta intensidade no ganho de força e hipertrofia. Material e métodos: n este ensaio clínico randomizado e controlado, 24 homens sedentários foram randomizados em do is grupo s: treino com restrição de fluxo sanguíneo ou treino resistido de alta intensidade. Ambos os grupos realizaram 10 sessões de exercício de preensão manual até com 3 séries de exercícios até a falha, sendo que o grupo com treino de restrição de fluxo sanguíneo realizou com 30% da carga máxima obtida no teste de 1 repetição máxima, enquanto que o grupo de alta intensidade realizou com 80% da carga. T odo s o s voluntários foram avaliados e reavaliados a dinamometriade preensão manual e a perimetria de antebraço. Os dados foram tabulados e analisados no statistical package for the social sciences, utilizando o teste t-student, e o não paramétrico u de mann whitney, adotando a significância de 5% (α = 0,05). Resultados: para o desfecho força, identificou-se que tanto o grupo que treino com restrição do fluxo, quanto o grupo que treinou com alta intensidade tiveram aumentos significativos (p= 0,005 e 0,026, respectivamente). Já em relação ao aumento da circunferência, notou-se que somente o treino de restrição do flux o se mostrou estatisticamente quando comparado o aumento entre os grupos (p= 0,00 1). Conclusão: foi possível concluir que o treinamento com restrição do fluxo sanguíneo mostrou eficaz tanto para o ganho de força, quanto para o aumento de circunferência, apresentando vantagens quando comparado ao grupo de treinamento resistido com alta intensidade...(AU)

Objectives: to compare the effects of blood flow restriction trainin g wit h h igh in tensity resistance training on strength gain and hypertrophy. Material and methods: in this randomized controlled trial, 24 sedentary men were randomized into two groups: restricted blood flow training or high inten sity resistance training. Both groups performed 10 handgrip exercise sessions up to 3 sets of exercises un t il failure, and the group with blood flow restriction training performed with 3 0 % o f t he m ax imum lo ad obtained in the 1-repetition maximum test, while the high intensity group performed with 80% of the load. All volunteers were assessed and reassessed by handgrip dynamometry and forearm perimetry. Data were tabulated and analyzed in the statistical package for the social sciences, using the t-studen t test an d t he non-parametric mann whitney u test, adopting the significance of 5% (α = 0.05). Results: for the stren gth outcome, it was found that both the flow restriction training group and the high intensity train in g gro up had significant increases (p = 0.005 and 0.026, respectively). Regarding the increase in circumference, it was noted that only the flow restriction training was statistically when compared to the increase bet ween the groups (p = 0.001). Conclusion: it was concluded that training with blood flow restriction was effective for both strength gain and circumference increase, presenting advantages when compared to the high intensity resistance training group...(AU)

Kaastu training for muscle fitness in the middle-aged and elderly adults: Effects and strengths / 中国组织工程研究

BACKGROUND: KAASTU training combined with low-load exercise can achieve the same effect as traditional high intensity resistance exercise. Therefore, it has been widely used in competitive sports, sports fitness, medical rehabilitation and other fields in recent years. However, there are few comments on the effects of KAASTU training on muscle fitness of the middle-aged and elderly adults. OBJECTIVE: To further explain and verify the safety, practicability and convenience of KAASTU training in the middle-aged and elderly adults exercise through a comprehensive review of the muscle fitness of middle-aged and elderly adults, and to provide scientific suggestions for the middle-aged and elderly adults to choose a safe and effective exercise. METHODS: Up to October 2019, Elsevier, PubMed, Springer, VIP, CNKI and Taiwan Academic Literature Database were searched for Chinese and English literature about KAASTU training, blood flow restriction, and muscle. Corresponding selection criteria was established according to the needs of the study, followed by literature screening. RESULTS AND CONCLUSION: KAASTU training combined with low-load exercise can effectively increase the muscle mass of the middle-aged and elderly adults, and has a positive effect on the prevention of muscle atrophy in the middle-aged and elderly adults. KAASTU training combined with low-load exercise can effectively improve the muscle strength of the lower extremities, which is beneficial to reduce exercise injury and improve the quality of life. KAASTU training has positive effects on bone health of the middle-aged and elderly adults, improves osteoporosis and increases bone mineral density of the older adults. Compared with traditional resistance training, KAASTU training is characterized by lower load and better effect. Therefore, KAASTU training is easier to be accepted by the middle-aged and elderly adults.

Physiological Effects of Strength Training Incorporating Blood Flow Restriction Underwater / 日本温泉気候物理医学会雑誌

  Strength training performed while restricting blood flow is believed to cause the secretion of growth hormones under low load intensities and allow for muscle hypertrophy and increased muscle strength. This has potential clinical applications for elderly individuals and people with existing conditions. However, previous research has been performed on land, with hemodynamics and growth hormone secretion trends for training performed underwater unclear. Against this background, we investigated the effects of blood flow restriction training underwater on hemodynamics and plasma growth hormone (GH) levels. Twelve healthy university students were divided into two groups: a localized immersion group where only the upper limb of the dominant hand was submerged, and a whole-body immersion group where participants were submerged to the xiphoid process. Immersed according to respective group protocols, both groups performed flexion and extension of the shoulder joint for 10 minutes with a pressurized cuff at the base of the upper arm under both 0 mmHg and 50 mmHg cuff pressures. Measured hemodynamics were heart rate, systolic blood pressure, and diastolic blood pressure. Plasma GH levels were measured from blood samples. This study revealed that underwater blood flow restriction strength training induced plasma GH level secretion under 50 mmHg conditions. In addition, high levels of GH secretion were shown in the localized immersion group for strength training even when the cuff was not pressurized. Conversely, no significant differences were evident in any measured hemodynamic categories. Results suggest that, in addition to cuff pressure, blood flow restriction training is affected by the body part immersed in water.

The Efficacy And Validity Of Blood Flow Restriction Training In Clinical And Post-Surgical Populations

Background: We currently know BFR training is a viable modality for strength gains in the healthy population. However, it is unknown the effect of BFR training on post-surgical and clinical populations. Furthermore, the optimal use of the BFR modality regarding resistance vs. no-resistance (bodyweight) is also unknown. This literature review adds new information to the field of BFR training specifically in the post-surgical and clinical populations. The objective of the study is to explore the validity and efficacy of blood-restriction training (BFR) in conjunction with low-load resistance training (LL-BFR) versus low-load training without BFR and high-load resistance training without BFR to determine which is superior for strength gains. Methods: The authors used SPORTDiscus, EBSCO, PubMed, and Science Direct to search for peer-reviewed articles. The articles chosen had the keywords/phrases “BFR,” “vascular occlusion,” “strength training,” “resistance training.” The studied emphasized patients with either clinical conditions (osteoarthritis) or musculoskeletal injuries (ACL reconstruction, total knee arthroplasty, knee arthroscopy). One hundred seventy-one articles were screened, and 17 articles reviewed. Results: BFR, in conjunction with low-load resistance training yields superior strength gains when compared to lowload training alone (p<.05). The outcome measures show a higher 1-rep max (isotonic strength) and greater muscle size (cross-sectional area, muscle mass, muscle volume) (p<.05). However, BFR with low-load resistance training does not yield superior strength gains in comparison to high-load resistance training alone (p<.03). Conclusion: As healthcare providers treating patients with musculoskeletal conditions, we know the importance of resistance training as a tool for rehabilitation and activities of daily living. However, at times heavy resistance training is contraindicated either due to joint instability/degeneration, pain, surgical restrictions. BFR training can be implemented with a 10-30% 1-rep max for comparable strength gains. This can be a potential tool used to offset post-surgical atrophy and atrophy due to arthralgia seen in certain systemic conditions. This can translate to better functional outcomes in post-surgical patients and superior quality of life in the geriatric population.

Exercício de força combinado à restrição de fluxo sanguíneo induz aumentos agudos na pressão arterial sistólica / Strength exercise combined to blood flow restriction induces acute increases in systolic blood pressure

Recentemente cresceu o número de pesquisas sobre o exercício de força (EF) de baixa intensidade (20-50% de 1RM) combinado à restrição do fluxo sanguíneo (RFS), mostrando adaptações semelhantes ao EF de alta intensidade. Entretanto, muitas questões sobre essa metodologia necessitam ser investigadas. O objetivo desse estudo foi analisar a resposta aguda da pressão arterial em repouso e durante o EF combinado à RFS. Dezesseis jovens (22±2 anos de idade), ativos e de ambos os sexos, realizaram o EF em duas diferentes condições, separadas por um intervalo de 48h: 1) Exercício isolado (EF) e 2) Exercício combinado à RFS (EF+RFS, 100 mmHg, porção proximal da coxa, mantida durante o exercício). Ambos realizaram 3 séries no exercício leg press com o membro dominante, à 30% de 1RM, 1 minuto de descanso, duração de 90 segundos cada série e cadência de 2 segundos, totalizando 22 repetições para a fase concêntrica e 23 para a fase excêntrica do movimento. Foram avaliadas a pressão arterial sistólica (PAS), diastólica (PAD), frequência cardíaca (FC), duplo produto (DP) e lactato sanguíneo nos momentos: repouso e imediatamente após o exercício. Foi observado apenas aumento significativo da PAS e do DP em repouso e da PAS durante o EF+RFS. O lactato sanguíneo não se alterou em nenhuma condição avaliada. Concluindo que o exercício de força com restrição de fluxo sanguíneo apresentou maiores respostas de pressão arterial sistólica em repouso e durante o exercício em sujeitos jovens ativos...(AU)

Recently, the number of researches about the strength exercise (SE) of low intensity (20- 50% of 1RM) combined to the blood flow restriction (BFR) increased, showing similar adaptations to the high-intensity SE. However, many questions about this methodology need be investigated. The purpose of this study was to analyze the acute response of blood pressure at rest and during SE combined with BFR. Sixteen young subjects (22 ± 2 years old), actives and of both sexs, underwent SE in two different conditions, separated by an interval of 48h: 1) isolated strength exercise (SE) and 2) strength exercise combined to BFR (SE+BFR, 100 mmHg, proximal portion of the thigh, maintained throughout the exercise session). Both conditions performed 3 sets on the leg press exercise with the dominant leg, with 30% of 1RM, 1 minute of rest, each series with 90 seconds of the duration and movement cadence of the 2 seconds, totaling 22 repetitions in the concentric phase and 23 in the eccentric phase of movement. Systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), double product (DP) and blood lactate were evaluated on rest and immediately after exercise moments. It was observed only significant increase in SBP and DP at rest and SBP during SE+BFR condition. Blood lactate did not change in any condition evaluated. Concluding that strength exercise with blood flow restriction showed higher responses of systolic blood pressure at rest and during exercise in active young subjects...(AU)

Entrenamiento de resistencia muscular en jóvenes universitarios ¿método de oclusión vascular o tradicional? / Resistance training in college students ¿vascular occlusion training or traditional method?

El objetivo del estudio fue determinar si existen diferencias significativas en la circunferencia del brazo y en el número de repeticiones realizadas en base a dos métodos de entrenamiento: oclusión vascular y tradicional. Se reclutaron ocho sujetos a los cuales, de manera aleatoria, se les asignó el método de oclusión vascular (OVbi) para un brazo y el entrenamiento tradicional (ETmi) para el otro. Se realizó un pretest en el cual se midió la circunferencia del brazo y la cantidad de repeticiones que pudieran realizar con una carga equivalente al 9% de la masa corporal. Después de cuatro semanas de tratamiento (tres sesiones por semana) se realizó el postest. Los resultados no encontraron interacción significativa en la circunferencia del brazo (p = 0.164) ni en la cantidad de repeticiones (p = 0.390), sin embargo, si se encontraron diferencias en la cantidad de repeticiones realizadas entre el pretest y postest (p = 0.048). Estos resultados demuestran que, independientemente del tratamiento (OVbi y ETmi), los sujetos aumentaron el número de repeticiones realizadas, en pocas palabras, un entrenamiento a baja intensidad con oclusión vascular durante cuatro semanas es igual de efectivo a un entrenamiento tradicional de moderada intensidad.

The purpose of the study was to determine the effect of vascular occlusion (VO) and traditional resistance training (TRT) methods on arm circumference and number of repetitions to exhaustion. Eight participants were randomly assigned to VO in one arm and TRT on the other. Before and after four weeks of training performed three times per week, measurements were obtained on arm circumference and number of repetitions with a workload equivalent to 9% of body mass. No significant treatment by measurements interactions were found on arm circumference (p = 0.164) and number of repetitions to exhaustion (p = 0.390). Regardless of the training method, participants improved number of repetition to exhaustion following the intervention (p = 0.048). In conclusion, four weeks of VO is as effective as TRT for improving arm muscular performance to exhaustion.

Effects of Knee Extension Exercise Using Blood Flow Restriction on the Thickness and Balance Ability of Tendons

PURPOSE: This study examined the effects of knee extension exercise using blood flow restriction on the changes in the thickness and static balance ability of the tendon of the rectus femoris muscle and achilles tendon. METHODS: A total of 30 subjects was were divided into two groups of 15 subjects each. The changes in the thickness and balance of their tendons were measured by ultrasonography and balance equipment. The measurements were taken three times: before the experiment, 4 weeks after, and 8 weeks after. The results were analyzed by repeated measure ANOVA, one-way ANOVA was conducted in cases where there were time-to-group interactions in the intra-individual effects test. RESULTS: Significant differences in the thickness of the tendon of the rectus femoris muscle and Achilles tendon were found between the groups, over time, and in the time-to-group interactions (p 0.05). CONCLUSION: Knee extension exercise using blood flow restriction leads to significant differences in the increase in tendon thickness and changes in balance, indicating that the results of this study can be utilized as basic data for future studies and for rehabilitation treatment at clinics.

Effects of Blood Flow Restriction and Different Support Surfaces on the Thickness of Type-I Muscle Fibers in the Trunk

PURPOSE: This study was conducted to investigate the effects of blood flow restriction and different support surfaces for bridge exercises on the thickness of the transverse abdominis and multifidus, which are trunk-stabilizing muscles. METHODS: The study's subjects were 45 adults who were divided into three groups that performed bridge exercises over a six-week period on their respective support surfaces after blood flow restriction. Changes in the thickness of the subjects' transverse abdominis and multifidus muscles were measured using ultrasonography before the experiment, then three and six weeks after the experiment. The changes in each variable over time were analyzed using a repeated-measures analysis of variance (ANOVA). RESULTS: The transverse abdominis showed significant differences in muscle thickness with regard to time and the interaction between time and each group (p0.05). The multifidus showed significant differences in muscle thickness with regard to time, the interaction between time and each group, and changes between groups (p<0.05). CONCLUSION: Blood flow restriction and different support surfaces for bridge exercises led to significant differences in the thickness of the transverse abdominis and multifidus. This study's results may be used as the basis for future studies and for rehabilitation in clinical practice.

Effects of Different Sizes of Blood Flow Restriction Areas on Changes in Muscle Thickness

PURPOSE: This study was conducted to examine the effects of different sizes of blood flow restriction areas on the thickness of the external oblique and biceps brachii. METHODS: The study subjects were 52 adults who were divided into four groups that performed plank exercises over a six-week period after blood flow restriction. Changes in the thickness of the external oblique and biceps brachii were measured using ultrasonography before the experiment, then three and six weeks after the experiment. The changes in each variable over time were evaluated by repeated-measures analysis of variance (ANOVA). RESULTS: The external oblique and biceps brachii showed significant differences in muscle thickness with regard to time and the interaction between time and each group (p0.05). CONCLUSION: A larger blood flow restriction area resulted in a statistically significant increase in muscle thickness. The results of this study may be used as the basis for future studies and for rehabilitation in clinical practice.

Effects of disturbed blood flow during exercise on endothelial function: a time course analysis

This study aimed to examine the time course of endothelial function after a single handgrip exercise session combined with blood flow restriction in healthy young men. Nine participants (28±5.8 years) completed a single session of bilateral dynamic handgrip exercise (20 min with 60% of the maximum voluntary contraction). To induce blood flow restriction, a cuff was placed 2 cm below the antecubital fossa in the experimental arm. This cuff was inflated to 80 mmHg before initiation of exercise and maintained through the duration of the protocol. The experimental arm and control arm were randomly selected for all subjects. Brachial artery flow-mediated dilation (FMD) and blood flow velocity profiles were assessed using Doppler ultrasonography before initiation of the exercise, and at 15 and 60 min after its cessation. Blood flow velocity profiles were also assessed during exercise. There was a significant increase in FMD 15 min after exercise in the control arm compared with before exercise (64.09%±16.59%, P=0.001), but there was no change in the experimental arm (-12.48%±12.64%, P=0.252). FMD values at 15 min post-exercise were significantly higher for the control arm in comparison to the experimental arm (P=0.004). FMD returned to near baseline values at 60 min after exercise, with no significant difference between arms (P=0.424). A single handgrip exercise bout provoked an acute increase in FMD 15 min after exercise, returning to near baseline values at 60 min. This response was blunted by the addition of an inflated pneumatic cuff to the exercising arm.

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

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.