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Öğe Blood flow restriction training prescription: percentage of lower limb arterial occlusion pressure at fixed values and based on brachial systolic blood pressure(Springer Nature, 2025) de Queiros, Victor S.; Rolnick, Nicholas; Kamış, Okan; Alves, Julio M.; Neto, Gabriel R.; Amorim, Samuel; Gonzaga, Jozilma Medeiros; Aniceto, Rodrigo R.; Cabral, Breno Guilherme de Araujo TinocoBlood flow restriction (BFR) exercise is recommended with personalized pressures between 40 and 80% of arterial occlusion pressure (AOP) to ensure safety and efficacy. However, many studies use fixed pressures or personalized pressures based on brachial blood pressure, such as 130% of resting brachial systolic pressure (rbSBP), which may lead to inconsistencies. This study aimed to estimate the percentage of AOP in the thigh when using fixed pressures (e.g., 100, 200, and 300 mmHg) or 130% of SBP.MethodsFifty-one healthy participants (18-40 years) underwent anthropometric measurements, brachial blood pressure assessment, and AOP determination in the thigh in supine, seated, and standing positions using an 18 cm cuff. AOP measurements were randomized and compared to fixed pressures and 130% of SBP.ResultsAOP was higher than 100 mmHg in all positions, with 100 mmHg corresponding to 80.5%, 62%, and 56.9% of AOP in the supine, seated, and standing positions, respectively. Conversely, 200 mmHg exceeded AOP, reaching 160.9%, 124.2%, and 113.7% in the same positions. Compared to SBP, supine AOP was lower than 130% of rbSBP, standing AOP was higher, and seated AOP showed no significant difference (p = 0.595). In the seated and standing positions, 130% of rbSBP corresponded to 92.5% and 84.7% of AOP, respectively.ConclusionA fixed pressure of 100 mmHg may fall within the recommended range for BFR prescription, but findings are specific to AOP assessment with an 18 cm cuff. Personalization remains crucial for accuracy and safety.Öğe Body position and cuff size influence lower limb arterial occlusion pressure and its predictors: implications for standardizing the pressure applied in training with blood flow restriction(Frontiers Media SA, 2025) de Queiros, Victor S.; Rolnick, Nicholas; Kamış, Okan; Formiga, Magno F.; Rocha, Roberto F. C.; Alves, Júlio César Medeiros; Vieira, João Guilherme; Vianna, Jeferson MacedoArterial occlusion pressure (AOP) is a relevant measurement for individualized prescription of exercise with blood flow restriction (BFRE). Therefore, it is important to consider factors that may influence this measure. Purpose: This study aimed to compare lower limb AOP (LL-AOP) measured with 11 cm (medium) and 18 cm (large) cuffs, in different body positions, and explore the predictors for each of the LL-AOP measurements performed. This information may be useful for future studies that seek to develop approaches to improve the standardization of pressure adopted in BFRE, including proposals for equations to estimate LL-AOP. Methods: This is a cross-sectional study. Fifty-one healthy volunteers (males, n = 25, females, n = 26; Age: 18–40 years old) underwent measurement of thigh circumference (TC), brachial blood pressure, followed by assessments of LL-AOP with medium and large cuffs in positions supine, sitting and standing positions. Results: The large cuff required less external pressure (mmHg) to elicit arterial occlusion in all three-body positions when compared to the medium cuff (p < 0.001). The LL-AOP was significantly lower in the supine position, regardless of the cuff used (p < 0.001). Systolic blood pressure was the main predictor of LL-AOP in the large cuff, while TC was the main predictor of LL-AOP with the medium cuff. Body position influenced strength of the LL-AOP predictors. Conclusion: Our results indicate that LL-AOP and its predictors are substantially influenced by body position and cuff width.Öğe Effects of different pre-exercise strategies on jumping performance in female volleyball players(Edizioni Minerva Medica, 2025) Keskin, Kadir; Akçay, Neslihan; Özmen, Tarık; Contarlı, Nurcan; Yıldız, Kerem C.; Sofuoğlu, Cem; Kamiş, Okan; Rolnick, Nicholas; de Queiros, Victor S.; Montoye, AlexanderThe present study aimed to compare different pre-exercise strategies on jumping performance in female volleyball players. METHODS: Fifteen healthy female volleyball players (age=18 +/- 0.6 years; training experience = 7.3 +/- 1.4 years; height = 164.8 +/- 5.4 cm; body mass = 57.2 +/- 8.1 kg) volunteered to participate in the study. Three different pre-exercise conditions (5 repetition maximum knee extension, electromyostimulation [EMS] and ischemic preconditioning [IPC]) were applied to the subjects and compared to a control condition performing a standardized warmup. Subjects performed the squat jump and 15 sec repeated countermovement jumps following a rest period. Measures associated with jumping performance were collected and compared between conditions. Rating of perceived exertion was also collected after each performance test. RESULTS: No pre-exercise condition outperformed a standardized warm-up on inducing improvements in jumping performance and in fact, EMS and IPC conditions resulted in performance decrements compared to control (P<0.05). CONCLUSIONS: We conclude that a standardized warm-up is enough to induce improvements in jumping performance in female volleyball players. Future research should examine alternative strategies alongside standardized warm-up to determine how best to prepare for jumping and related sport-specific tasks in female volleyball players.Öğe Impact of limb occlusion pressure assessment position on performance, cardiovascular, and perceptual responses in blood flow restricted low-load resistance exercise: A randomized crossover trial(Taylor & Francis, 2025) Kamış, Okan; Rolnick, Nicholas; de Queiros, Victor S; Akçay, Neslihan; Keskin, Kadir; Yıldız, Kerem Can; Werner, Tim; Hughes, Luke; Sofuoğlu, CemThis study investigated the effect of limb occlusion pressure (LOP) position on exercise performance, cardiovascular responses, and perceptual experiences during seated bilateral leg extensions with and without blood flow restriction (BFR). Thirty resistance-trained males (age: 22?±?2?years; weight: 74.4?±?13.6?kg; height: 177.4?±?6.4?cm; BMI: 23.5?±?3.3?kg/m2) participated. Each performed exercise to failure (4 sets, 30% 1RM, 1?min rest) in three conditions: Supine LOP-BFR, Seated LOP-BFR, and no-BFR. BFR was applied at 60% LOP. Significant interaction effects were found for RPE (p?=?0.021, d?=?0.76), RPD (p?Öğe Why blood flow restriction cuff features are an important methodological consideration- a short commentary on “cerebral cortex activation and functional connectivity during low-load resistance training with blood flow restriction: an fNIRS study”(Frontiers Media SA, 2024) Rolnick, Nicholas; Clarkson, Matthew; Korakakis, Vasileios; De Queiros, Victor; Patterson, Stephen D.; Buckner, Samuel; Werner, Tim; Nascimento, Dahan Da Cunha; Stray-Gundersen, Sten; Kamış, Okan; Thoelen, MathiasWe read with great interest the recent study titled “Cerebral cortex activation and functional connectivity during low-load resistance training with blood flow restriction: An fNIRS study” published in PLOS ONE earlier this year (Jia et al., 2024). The study adds to our limited understanding of the cerebral demands of blood flow restriction (BFR) exercise and the potential role of applied pressure. The authors examined cerebral oxygenation levels following squat exercise performed at 30% of one repetition maximum, with bilateral BFR applied at 150, 250, and 350 mmHg using the B-Strong cuffs (B-Strong, USA). The authors noted enhanced cerebral oxygenation levels in many cortical regions which dropped sharply when 350 mmHg was applied.
