Short-Term Blood Flow Restriction Increases Power Output and Bar Velocity During the Bench Press

Blood Flow Restriction Training: A Tool to Enhance Rehabilitation and Build Athlete Resiliency

Blood flow restriction training (BFRT) is a tool utilized in rehabilitation and injury prevention to improve muscle strength and size, particularly in load-compromised individuals. BFRT facilitates gains in muscular strength and hypertrophy at lower loads, allowing for accelerated recovery and less disuse atrophy. BFRT must be applied appropriately and with caution, particularly in individuals with cardiovascular concerns. There are applications for BFRT across a wide spectrum of human performance training and in rehabilitation of both lower and upper extremity conditions, providing a high-quality adjunct to improve muscle strength, power, and endurance.

Level of Evidence

Level V, expert opinion.

Blood flow restriction during high load bench press does not increase bar velocity or cause physiological changes in non-occluded agonist muscles

PURPOSE

Blood blow restriction (BFR) can increase peak velocity and power during high load resistance training. However, previous research primarily utilized high occlusion pressures (i.e., greater than 80% arterial occlusion pressure (AOP)), and rarely measured the physiological response during or after the bench press stimuli. The aim of this study was to investigate the application of 50%AOP during acute high load bench press exercise on barbell power, velocity, and the physiological responses to this stimulus.

METHODS

Resistance trained males (n = 12, 26.2 ± 6.6 yrs., 84.0 ± 10.8 kg, 176.3 ± 10.4 cm) completed a maximum strength test followed by two experimental sessions which consisted of four sets of 4 reps of the barbell bench press at 75%1RM, with or without BFR applied to both arms at 50% AOP. Significance was set to p ≤ 0.05. A series of two-way repeated measures ANOVAs with Bonferroni post hoc corrections tested for potential changes in bar velocity, power, blood lactate, and muscle thickness and activation of the anterior deltoid and pectoralis major.

RESULTS

There were no main effects for the interaction terms "Condition×Set" or "Condition×Time," nor for "Condition" for any variables (all p > 0.05). There was a "Time" effect for blood lactate (p < 0.001) with lactate increasing from pre- to postexercise, and a main effects for "Set" for mean (p = 0.016) and peak velocity (p = 0.005).

CONCLUSION

There was no difference in the change in velocity, or physiological responses during high load bench press with or without BFR at 50%AOP. While promising, use of BFR for upper body power may require pressures >50%AOP.

Physiological adaptations and performance enhancement with combined blood flow restricted and interval training: A systematic review with meta-analysis

OBJECTIVES

We aimed to determine: (a) the chronic effects of interval training (IT) combined with blood flow restriction (BFR) on physiological adaptations (aerobic/anaerobic capacity and muscle responses) and performance enhancement (endurance and sprints), and (b) the influence of participant characteristics and intervention protocols on these effects.

METHODS

Searches were conducted in PubMed, Web of Science (Core Collection), Cochrane Library (Embase, ClinicalTrials.gov, and International Clinical Trials Registry Platform), and Chinese National Knowledge Infrastructure on April 2, with updates on October 17, 2024. Pooled effects for each outcome were summarized using Hedge's g (g) through meta-analysis-based random effects models, and subgroup and regression analyses were used to explore moderators.

RESULTS

A total of 24 studies with 621 participants were included. IT combined with BFR (IT+BFR) significantly improved maximal oxygen uptake (VO2max) (g = 0.63, I2 = 63%), mean power during the Wingate 30-s test (g = 0.70, I2 = 47%), muscle strength (g = 0.88, I2 = 64%), muscle endurance (g = 0.43, I2 = 0%), time to fatigue (g = 1.26, I2 = 86%), and maximal aerobic speed (g = 0.74, I2 = 0%) compared to IT alone. Subgroup analysis indicated that participant characteristics including training status, IT intensity, and IT modes significantly moderated VO2max (subgroup differences: p < 0.05). Specifically, IT+BFR showed significantly superior improvements in VO2max compared to IT alone in trained individuals (g = 0.76) at supra-maximal intensity (g = 1.29) and moderate intensity (g = 1.08) as well as in walking (g = 1.64) and running (g = 0.63) modes. Meta-regression analysis showed cuff width (β = 0.14) was significantly associated with VO2max change, identifying 8.23 cm as the minimum threshold required for significant improvement. Subgroup analyses regarding muscle strength did not reveal any significant moderators.

CONCLUSION

IT+BFR enhances physiological adaptations and optimizes aspects of endurance performance, with moderators including training status, IT protocol (intensity, mode, and type), and cuff width. This intervention addresses various IT-related challenges and provides tailored protocols and benefits for diverse populations.

Effects of Blood flow Restriction and Load on Mean Propulsive Velocity and Subjective Perceived Exertion During Squat and Bench Press Exercises

BACKGROUND

The aim of this study was to determine the influence of different percentages of blood flow restriction (BFR) and loads on mean propulsive velocity (MPV) and subjective perceived exertion during squat (SQ) and bench press (BP) exercises.

HYPOTHESIS

Higher percentages of BFR will positively affect dependent variables, increasing MPV and reducing perceived exertion.

STUDY DESIGN

Cross-sectional study.

LEVEL OF EVIDENCE

Level 3.

METHODS

Eight healthy young male athletes took part. Two sets of 6 repetitions at 70% 1-repetition maximum (1RM), 2 sets of 4 repetitions at 80% 1RM, and 2 sets of 2 repetitions at 90% 1RM were performed randomly; 5-minute recoveries were applied in all sets. The varying arterial occlusion pressure (AOP) applied randomly was 0% (Control [CON]), 80%, and 100%.

RESULTS

No statistically significant differences in MPV were found during the BP exercise at any percentage of BFR at any percentage 1RM. During the SQ exercise, MPV results showed statistically significant increases of 5.46% (P = 0.04; ηp2 = 0.31) between CON and 100% AOP at 90% 1RM. The perceived exertion results for the BP exercise showed statistically significant reductions of -8.66% (P < 0.01; ηp2 = 0.06) between CON and 100% AOP at 90% 1RM. During the SQ exercise, the perceived exertion results showed significant reductions of -10.04% (P = 0.04; ηp2 = 0.40) between CON and 100% AOP at 80% 1RM; -5.47% (P = 0.02; ηp2 = 0.48) between CON and 80% AOP at 90% 1RM; and -11.83% (P < 0.01; ηp2 = 0.66) between CON and 100% AOP at 90% 1RM.

CONCLUSION

BFR percentages ~100% AOP at 90% 1RM improved acutely MPV (only in SQ exercises) and reduced acutely perceived exertion (in both exercises). These findings are important to consider when prescribing resistance training for healthy male athletes.

Acute Responses of Low-Load Resistance Exercise with Blood Flow Restriction

Blood flow restriction (BFR) is a popular resistance exercise technique purported to increase metabolic stress and augment training adaptations over time. However, short-term use may lead to acute neuromuscular fatigue and higher exertion ratings. Objective: The purpose of the current study was to examine acute physiological responses to low-load resistance exercise utilizing BFR compared to higher-load, non-BFR resistance exercise. Methods: Recreationally trained males (n = 6) and females (n = 7) (mean ± standard deviation, age: 20 ± 1 yrs.; height: 172 ± 8 cm; weight: 73 ± 11 kg; BMI: 24.4 ± 2.2 kg·m-2; training experience: 4 ± 2 yrs.) had limb occlusion pressure determined (50%; right leg: 118 ± 11 mmHg; left leg: 121 ± 13 mmHg) using an automated, self-inflating cuff system during baseline testing. In subsequent sessions, using a randomized, cross-over design, participants completed one of two experimental conditions: (1) Low-load + BFR and (2) High load + non-BFR. In both conditions, participants completed one set of back squats at either 30% (BFR) or 60% (non-BFR) of an estimated 1RM for a max of 30 repetitions, followed by three additional sets with the same loads and a target of 15 repetitions per set. Blood lactate and countermovement jump (CMJ) height were measured pre- and post-back squat. Ratings of perceived exertion (RPE) were assessed following each set. Results: When collapsed across all sets, participants completed significantly more total repetitions in the BFR condition compared to non-BFR (75.0 ± 0.0 vs. 68.23 ± 9.27 reps; p = 0.015; ES: 1.03), but a lower training load volume (2380 ± 728 vs. 4756 ± 1538 kg; p < 0.001; ES: 1.97). There was a significant time-by-condition interaction (p < 0.001), with a greater increase in blood lactate occurring from baseline to post-back squat in the non-BFR condition (11.61 mmol/L, 95%CI: 9.93, 13.28 mmol/L) compared to BFR (5.98 mmol/L, 95%CI: 4.30, 7.65 mmol/L). There was another significant time-by-condition interaction (p = 0.043), with a greater reduction in CMJ occurring in the non-BFR condition (-6.01, 95%CI: -9.14, -2.88 cm; p < 0.001) compared to BFR (-1.50, 95%CI: -1.50, 4.51 cm; p = 0.312). Conclusions: Utilizing a low-load BFR protocol may allow for a higher training volume, yet lower metabolic stress and reduce neuromuscular fatigue compared to lifting at a higher load without the use of BFR.

The effects of blood flow restriction training on post activation potentiation and upper limb muscle activation: a meta-analysis

OBJECTIVE

This meta-analysis aims to systematically evaluate the impact of blood flow restriction training (BFRT) on muscle activation and post-activation potentiation (PAP) in the upper limbs, to provide guidance for upper limb protocols aiming to enhance explosive strength and activation.

METHODS

PubMed, CNKI, Web of Science, and EBSCO databases were queried to identify randomized controlled trials (RCTs) investigating the effects of upper limb BFRT on muscle activation and PAP. Inclusion and exclusion criteria were applied using the Cochrane bias risk tool. Literature quality assessment and statistical analysis were conducted using Revman 5.4 and Stata 17.0 software. Sensitivity analysis and funnel plots were utilized to assess result stability and publication bias.

RESULTS

A total of 31 articles involving 484 participants were included in the analysis. Meta-analysis results showed that upper limb BFRT significantly increased muscle iEMG values [SMD = 0.89, 95%CI (0.21, 1.58), p = 0.01]. BFRT had a significant effect on upper limb explosive force [SMD = 0.73, 95%CI (0.41, 1.04), p < 0.00001]. Subgroup analysis based on literature heterogeneity (I 2 = 92%, 80%) showed that exhaustive BFRT significantly decreased upper limb iEMG [SMD = -0.67, 95%CI (-1.25, -0.09), p = 0.01], with exercise modes including maximum output power of bench press [SMD = 1.87, 95%CI (0.22, 3.53), p < 0.0001], exercise intensity of 40%-70% 1RM [SMD = 1.31, 95%CI (0.61, 2.01), p < 0.0001], and pressure intensity of ≥60% AOP [SMD = 0.83, 95%CI (0.43, 1.23), p < 0.0001] reaching maximum effects and statistical significance.

CONCLUSION

Upper limb BFRT can induce muscle activation and PAP. BFRT with 40%-70% 1RM and ≥60% AOP in the upper limbs is more likely to promote PAP.

SYSTEMATIC REVIEW REGISTRATION

http://inplasy.com, identifier INPLASY202430008.

Complex training with blood flow restriction increases power output and bar velocity during half-squat jump: a pilot randomized controlled study

Purpose

This study examined the effects of 8-week complex training (CT) with blood flow restriction (BFR) on power output and bar velocity.

Methods

Twenty-six healthy male university athletes (age: 19.40 ± 0.88 years) completed three sessions of CT with BFR (CT_BFRT, n = 13) or CT-only (i.e., control) (n = 13) per week (i.e., 24 sessions in total). Before and immediately after intervention, participants completed power measurement as assessed by one-repetition maximum (1RM) squat, squat jump (SJ), countermovement jump (CMJ), and mean power (MP), peak power (PP), mean bar velocity (Bar-MV), and peak bar velocity (Bar-PV) during the half-squat jump.

Results

Two-way ANOVA models showed significant main effect of time (p < 0.001) but not group (p > 0.89) or interaction (p > 0.37) between group and time on 1RM of the squat, SJ, or CMJ; however, significant interactions were observed in MP (p = 0.03, Cohen's d = 1.39), PP (p = 0.03, Cohen's d = 1.14), Bar-MV (p = 0.049, Cohen's d = 1.26), and Bar-PV (p = 0.01, Cohen's d = 1.56). The post hoc analyses revealed that MP, PP, Bar-MV, and Bar-PV after CT with BFRT were significantly greater compared to all the other three conditions (i.e., pre-CT_BFRT, pre- and post-CT-only).

Conclusion

CT with BFR may induce significantly greater improvements in power output and bar velocity during half-squat jump and induce comparable improvements in 1RM of the squat, SJ, and CMJ of males as compared to CT only, suggesting this novel CT with BFR would be a promising strategy to enhance power performance in healthy male university athletes.

Update on Current Concepts of Blood Flow Restriction in the Perioperative Period of Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament tears or ruptures are common orthopedic injuries. Anterior cruciate ligament reconstruction (ACLR) is an orthopedic procedure allowing for earlier return to sports, improved maintenance of lifestyle demands, and restored knee stability and kinematics. A perioperative rehabilitative adjunct recently gaining interest is blood flow restriction (BFR), a method in which temporary restriction of blood flow to a chosen extremity is introduced and can be used as early as a few days postoperative. There has been increasing investigation and recent literature regarding BFR. This review synthesizes current concepts of BFR use in the ACLR perioperative period. [Orthopedics. 2023;46(6):e333-e340.].

Where Does Blood Flow Restriction Fit in the Toolbox of Athletic Development? A Narrative Review of the Proposed Mechanisms and Potential Applications

Blood flow-restricted exercise is currently used as a low-intensity time-efficient approach to reap many of the benefits of typical high-intensity training. Evidence continues to lend support to the notion that even highly trained individuals, such as athletes, still benefit from this mode of training. Both resistance and endurance exercise may be combined with blood flow restriction to provide a spectrum of adaptations in skeletal muscle, spanning from myofibrillar to mitochondrial adjustments. Such diverse adaptations would benefit both muscular strength and endurance qualities concurrently, which are demanded in athletic performance, most notably in team sports. Moreover, recent work indicates that when traditional high-load resistance training is supplemented with low-load, blood flow-restricted exercise, either in the same session or as a separate training block in a periodised programme, a synergistic and complementary effect on training adaptations may occur. Transient reductions in mechanical loading of tissues afforded by low-load, blood flow-restricted exercise may also serve a purpose during de-loading, tapering or rehabilitation of musculoskeletal injury. This narrative review aims to expand on the current scientific and practical understanding of how blood flow restriction methods may be applied by coaches and practitioners to enhance current athletic development models.

Effects of Resistance Training with Blood Flow Restriction on Explosive Power of Lower Limbs: A Systematic Review and Meta-Analysis

The purpose of this systematic review and meta-analysis was to compare changes in explosive power between blood flow restriction training and traditional resistance training protocols. Searches of PubMed, Scopus, Web of Science, and OVID Medline were conducted for studies. Inclusion criteria were: (a) healthy people; (b) randomized controlled or controlled trials; (c) outcome measures of explosive performance (peak power, rate of force development, jump performance, sprint performance, etc.); (d) involving a comparison between blood flow restriction training and traditional resistance training. Quality assessment was conducted using the Physiotherapy Evidence Database (PEDro) scale. A total of 12 studies (262 subjects) were finally included for analysis. The PEDro scale score had a median of 5 of 10 points (range: 3-6 points). Significant small to moderate improvements were observed in blood flow restriction training [jump: standard mean difference (SMD) of 0.36 (95% CI: 0.02; 0.69); sprint: SMD of 0.54 (95% CI: 0.00; 1.07); power: SMD of 0.72 (95% CI: 0.17; 1.27)] when compared to traditional resistance training. The findings indicate that blood flow restriction training is more effective in improving explosive power of lower limbs compared to traditional resistance training in healthy people. In addition, blood flow restriction with a wide cuff (≥ 10 cm) during training improved explosive power better than with a narrow cuff or during the rest interval. Blood flow restriction training is very suitable for athletes in short competitive seasons and those who are not able to tolerate high loads (i.e., rehabilitators and the elderly).

Research hotspots and new trends in the impact of resistance training on aging, bibliometric and visual analysis based on CiteSpace and VOSviewer

Purpose

Resistance training (RT) can intervene in aging, which can effectively improve trainees' life. However, unhealthy living habits such as irregular life, obesity and hyperlipidemia, and chronic diseases lead to a significant decline in the energy level of the population, seriously affecting the health of the population. Our research identifies the research hotspots of RT to intervene in aging from the perspective of bibliometrics, predicts research frontiers and development trends, and provides more perspectives for research on aging populations.

Methods

In this study, we used CiteSpace and VOSviewer visualization software to draw the scientific knowledge map of countries/regions, institutions, authors, co-occurrence keywords, and co-cited references of published articles, and explore the Web of Science core collection database all about the RT intervention aging research status, hotspots, frontiers, and development trends of articles on aging.

Results

Among the 760 articles that meet the inclusion criteria, the number of articles published and the frequency of citations have increased steadily in the past 5 years. Judging from the countries/regions, institutions, scholars, and journals that published articles, the ones with the largest numbers are the USA, Univ Estadual Londrina, Cyrino ES, and Exp Gerontol. The ones with the highest influence are England, Univ Arkansas Med Sci, Frontera WR, and Biochem Biophys Rep Co. The top five co-occurrence keywords of include exercise, strength, resistance training, skeletal muscle, and muscle strength. The research frontier is physical function.

Conclusion

In the field of RT intervention aging research, relevant scholars deserve further in-depth research and exploration. The United States, Brazil, Canada, and other economically developed countries/regions, institutions, and authors have greater influence and productivity. These quantitative research results can provide references for relevant scholars' follow-up research and government departments to formulate and modify health policies or measures.

The Influence on Post-Activation Potentiation Exerted by Different Degrees of Blood Flow Restriction and Multi-Levels of Activation Intensity

(1) Background: To explore the influence on post-activation potentiation (PAP) when combining different degrees of blood flow restriction (BFR) with multi-levels of resistance training intensity of activation. (2) Purpose: To provide competitive athletes with a more efficient and feasible warm-up program. (3) Study Design: The same batch of subjects performed the vertical jump test of the warm-up procedure under different conditions, one traditional and six BFR procedures. (4) Methods: Participants performed seven counter movement jump (CMJ) tests in random order, including 90% one repetition maximum (1RM) without BFR (CON), and three levels of BFR (30%, 50%, 70%) combined with (30% and 50% 1RM) (BFR-30-30, BFR-30-50, BFR-50-30, BFR-50-50, BFR-70-30 and BFR-70-50). Jump height (H), mean power output (P), peak vertical ground reaction force (vGRF), and the mean rate of force development (RFD) were recorded and measured. (5) Results: Significantly increasing results were observed in: jump height: CON (8 min), BFR-30-30 (0, 4 min), BFR-30-50 (4, 8 min), BFR-50-30 (8 min), BFR-50-50 (4, 8 min), BFR-70-30 (8 min), (p < 0.05); and power output: CON (8 min), BFR-30-30 (0, 4 min), BFR-30-50 (4 min), BFR-50-30 (8 min), BFR-50-50 (4, 8 min) (p < 0.05); vGRF: CON (8 min), BFR-30-30 (0, 4 min), BFR-30-50 (4, 8 min), BFR-50-30 (4 min), BFR-50-50 (4, 8 min) (p < 0.05); RFD: CON (8 min), BFR-30-30 (0, 4 min), BFR-30-50 (4 min), BFR-50-30 (4 min), BFR-50-50 (4 min) (p < 0.05). (5) Conclusions: low to moderate degrees of BFR procedures produced a similar PAP to traditional activation. Additionally, BFR-30-30, BFR-30-50, and BFR-50-50 were longer at PAP duration in comparison with CON.

Resistance Training with Blood Flow Restriction and Ocular Health: A Brief Review

Despite the many health benefits of resistance training, it has been suggested that high-intensity resistance exercise is associated with acute increases in intraocular pressure which is a significant risk factor for the development of glaucomatous optic nerve damage. Therefore, resistance training using a variety of forms (e.g., resistance bands, free weights, weight machines, and bodyweight) may be harmful to patients with or at risk of glaucoma. An appropriate solution for such people may involve the combination of resistance training and blood flow restriction (BFR). During the last decade, the BFR (a.k.a. occlusion or KAATSU training) method has drawn great interest among health and sports professionals because of the possibility for individuals to improve various areas of fitness and performance at lower exercise intensities. In comparison to studies evaluating the efficiency of BFR in terms of physical performance and body composition changes, there is still a paucity of empirical studies concerning safety, especially regarding ocular health. Although the use of BFR during resistance training seems feasible for glaucoma patients or those at risk of glaucoma, some issues must be investigated and resolved. Therefore, this review provides an overview of the available scientific data describing the influence of resistance training combined with BFR on ocular physiology and points to further directions of research.

A Comparison of Electromyographic Inter-Limb Asymmetry During a Standard Versus a Sling Shot Assisted Bench Press Exercise

The objective of this study was to compare peak surface electromyography (sEMG) activity of selected muscles along with inter-limb asymmetries between a control (CONT) and a Sling shot assisted (SS) bench press exercise. Ten resistance-trained males with at least three-year experience in resistance training (22.2 ± 1.9 years, 88.7 ± 11.2 kg, 179.5 ± 4.1 cm, bench press one-repetition maximum (1RM) = 127.3 ± 25.9 kg) performed the flat bench press exercise under two conditions at selected loads (85% and 100% of 1RM assessed without the SS). Peak sEMG amplitude of triceps brachii, pectoralis major, and anterior deltoid was recorded for the dominant and the non-dominant side of the body during each attempt. The comparison between the dominant and the non-dominant side was carried out using the limb symmetry index (LSI(%) = (2*(XR - XL)/(XR + XL))*100%) where XR = values of the right side and XL = values of the left side. There was a main effect of condition (p = 0.004; η² = 0.64) and the load (p = 0.004; η² = 0.63) for the triceps brachii LSI in parallel with a main effect of condition (p = 0.003; η² = 0.42) for the anterior deltoid LSI. Post hoc analysis for the main effect of condition showed significant differences in the LSI between the CONT and SS conditions for the triceps brachii (p = 0.003; 1.10% vs. -8.78%) as well as for the anterior deltoid muscles (p = 0.03; 12.91% vs. 9.23%). The results indicate that the assistance of the Sling shot significantly affects the sEMG activity pattern on both the dominant and non-dominant sides of the body while influencing inter-limb asymmetries.

Ischemia during rest intervals between sets prevents decreases in fatigue during the explosive squat exercise: a randomized, crossover study

The study aimed to evaluate the impact of ischemia, used only before particular sets of a lower limb resistance exercise on power output. Ten healthy resistance-trained males (age = 26 ± 6 years; body mass = 90 ± 9 kg; training experience = 9 ± 7 years) performed two experimental sessions (with ischemia; control without ischemia) following a randomized crossover design. During the ischemic condition, the cuffs were inflated to 60% of arterial occlusion pressure. The cuffs were applied before each set for 4.5 min and released 30 s before the start of the set as the reperfusion (4.5 min ischemia + 0.5 min reperfusion). In the control condition, ischemia was not applied. During the experimental sessions, the subjects performed the Keiser machine squat exercise protocol which consisted of 5 sets of two repetitions, at a load of 60% of one-repetition maximum (1RM), with 5 min rest intervals between sets. The repetitions were performed with maximal velocity. The two-way repeated-measures ANOVA showed a statistically significant interaction effect for power output (p < 0.01; η² = 0.26). There was also a statistically significant main effect of condition for power output (p = 0.02; η² = 0.40). The post hoc analysis for interaction did not show significant differences between conditions in particular sets. The post hoc analysis for the main effect of the condition revealed that power output was significantly lower in the control group compared to the group where ischemic was used (p = 0.02). The t-test comparisons for particular sets showed a significant lower power output in set 3 (p = 0.03); set 4 (p < 0.01) and set 5 (p < 0.01) for the control condition when compared to the ischemic condition. The results indicate that ischemia applied before each set and released 30 s prior to the start of the squat exercise did not increase power output performance. However, we observed a significantly lower decline in power for the ischemic condition (4.5 min ischemia + 0.5 min reperfusion) in sets 3–5 compared to the control condition. Thus repeated ischemia with reperfusion used between sets can be an effective form of performance enhancement by preventing or at least diminishing fatigue during resistance exercise.

Acute Effects of Different Intensities during Bench Press Exercise on the Mechanical Properties of Triceps Brachii Long Head

This study aimed to analyze acute changes in the muscle mechanical properties of the triceps brachii long head after bench press exercise performed at different external loads and with different intensities of effort along with power performance. Ten resistance-trained males (age: 27.7 ± 3.7 yr, body mass: 90.1 ± 17.1 kg, height: 184 ± 4 cm; experience in resistance training: 5.8 ± 2.6 yr, relative one-repetition maximum (1RM) in the bench press: 1.23 ± 0.22 kg/body mass) performed two different testing conditions in a randomized order. During the experimental session, participants performed four successive sets of two repetitions of the bench press exercise at: 50, 70, and 90% 1RM, respectively, followed by a set at 70% 1RM performed until failure, with a 4 min rest interval between each set. Immediately before and after each set, muscle mechanical properties of the dominant limb triceps brachii long head were assessed via a Myoton device. To determine fatigue, peak and average barbell velocity were measured at 70% 1RM and at 70% 1RM until failure (only first and second repetition). In the control condition, only muscle mechanical properties at the same time points after the warm-up were assessed. The intraclass correlation coefficients indicated “poor” to “excellent” reliability for decrement, relaxation time, and creep. Therefore, these variables were excluded from further analysis. Three-way ANOVAs (2 groups × 2 times × 4 loads) indicated a statistically significant group × time interaction for muscle tone (p = 0.008). Post hoc tests revealed a statistically significant increase in muscle tone after 70% 1RM (p = 0.034; ES = 0.32) and 90% 1RM (p = 0.011; ES = 0.56). No significant changes were found for stiffness. The t-tests indicated a significant decrease in peak (p = 0.001; ES = 1.02) and average barbell velocity (p = 0.008; ES = 0.8) during the first two repetitions of a set at 70% 1RM until failure in comparison to the set at 70% 1RM. The results indicate that low-volume, high-load resistance exercise immediately increases muscle tone but not stiffness. Despite no significant changes in the mechanical properties of the muscle being registered simultaneously with a decrease in barbell velocity, there was a trend of increased muscle tone. Therefore, further studies with larger samples are required to verify whether muscle tone could be a sensitive marker to detect acute muscle fatigue.

Acute impact of blood flow restriction on strength-endurance performance during the bench press exercise

The main goal of the present study was to evaluate the acute effects of blood flow restriction (BFR) at 70% of full arterial occlusion pressure on strength-endurance performance during the bench press exercise. The study included 14 strength-trained male subjects (age = 25.6 ± 4.1 years; body mass = 81.7 ± 10.8 kg; bench press 1 repetition maximum (1RM) = 130.0 ± 22.1 kg), experienced in resistance training (3.9 ± 2.4 years). During the experimental sessions in a randomized crossover design, the subjects performed three sets of the bench press at 80% 1RM performed to failure with two different conditions: without BFR (CON); and with BFR (BFR). Friedman's test showed significant differences between BFR and CON conditions for the number of repetitions performed (p < 0.001); for peak bar velocity (p < 0.001) and for mean bar velocity (p < 0.001). The pairwise comparisons showed a significant decrease for peak bar velocity and mean bar velocity in individual Set 1 for BFR when compared to CON conditions (p = 0.01 for both). The two-way repeated measures ANOVA showed a significant main effect for the time under tension (p = 0.02). A post-hoc comparisons for the main effect showed a significant increase in time under tension for BFR when compared to CON (p = 0.02). The results of the presented study indicate that BFR used during strength-endurance exercise generally does not decrease the level of endurance performance, while it causes a drop in bar velocity.

The Evolution of Blood Flow Restricted Exercise

The use of blood flow restricted (BFR) exercise has become an accepted alternative approach to improve skeletal muscle mass and function and improve cardiovascular function in individuals that are not able to or do not wish to use traditional exercise protocols that rely on heavy loads and high training volumes. BFR exercise involves the reduction of blood flow to working skeletal muscle by applying a flexible cuff to the most proximal portions of a person’s arms or legs that results in decreased arterial flow to the exercising muscle and occluded venous return back to the central circulation. Safety concerns, especially related to the cardiovascular system, have not been consistently reported with a few exceptions; however, most researchers agree that BFR exercise can be a relatively safe technique for most people that are free from serious cardiovascular disease, as well as those with coronary artery disease, and also for people suffering from chronic conditions, such as multiple sclerosis, Parkinson’s, and osteoarthritis. Potential mechanisms to explain the benefits of BFR exercise are still mostly speculative and may require more invasive studies or the use of animal models to fully explore mechanisms of adaptation. The setting of absolute resistive pressures has evolved, from being based on an individual’s systolic blood pressure to a relative measure that is based on various percentages of the pressures needed to totally occlude blood flow in the exercising limb. However, since several other issues remain unresolved, such as the actual external loads used in combination with BFR, the type of cuff used to induce the blood flow restriction, and whether the restriction is continuous or intermittent, this paper will attempt to address these additional concerns.

Impact of Movement Tempo Distribution on Bar Velocity During a Multi-Set Bench Press Exercise

The goal of the present study was to evaluate the effect of contrast tempo movement on bar velocity changes during a multi-set bench press exercise. In randomized and counter-balanced order, participants performed three sets of the bench press exercise at 60%1RM under two testing conditions: E-E where all repetitions were performed with explosive (X/0/X/0) movement tempo; and S-E where the first two repetitions were performed with a slow tempo (5/0/X/0) while the third repetition was performed with explosive movement tempo (slow, slow, explosive). Twelve healthy men volunteered for the study (age = 30 ± 5 years; body mass = 88 ± 10 kg; bench press 1RM = 145 ± 24 kg). The three-way repeated measures ANOVA (tempo × set × repetition) showed statistically significant multi-interaction effect for peak bar velocity (p < 0.01; η2 = 0.23), yet not for mean bar velocity (p = 0.09; η2 = 0.14). The post hoc results for multi-interaction revealed that peak bar velocity in the 3^rd repetition was significantly higher for E-E compared to SE only during set 1 (p < 0.001). Therefore, the distribution of movement tempo had a significant impact on peak bar velocity, but not on mean bar velocity. The decrease in peak bar velocity in the 3^rd repetition during the S-E condition was observed only in the first set, while such a tendency was not observed in the second and third set.

The Effects of Ischemia During Rest Intervals on Bar Velocity in the Bench Press Exercise With Different External Loads

The main aim of the present study was to evaluate the acute effects of ischemia used during rest periods on bar velocity changes during the bench press exercise at progressive loads, from 20 to 90% of 1RM. Ten healthy resistance trained men volunteered for the study (age = 26.3 ± 4.7 years; body mass = 89.8 ± 6.3 kg; bench press 1RM = 142.5 ± 16.9 kg; training experience = 7.8 ± 2.7 years). During the experimental sessions the subjects performed the bench press exercise under two different conditions, in a randomized and counterbalanced order: (a) ischemia condition, with ischemia applied before the first set and during every rest periods between sets, and (b) control condition where no ischemia was applied. During each experimental session eight sets of the bench press exercise were performed, against loads starting from 20 to 90% 1RM, increased progressively by 10% in each subsequent set. A 3-min rest interval between sets was used. For ischemia condition the cuffs was applied 3 min before the first set and during every rest period between sets. Ischemia was released during exercise. The cuff pressure was set to ∼80% of full arterial occlusion pressure. The two-way repeated measures ANOVA showed a statistically significant interaction effect for peak bar velocity (p = 0.04) and for mean bar velocity (p = 0.01). There was also a statistically significant main effect of condition for peak bar velocity (p < 0.01) but not for mean bar velocity (p = 0.25). The post hoc analysis for interaction showed significantly higher peak bar velocity for the ischemia condition compared to control at a load of 20% 1RM (p = 0.007) and at a load of 50% 1RM (p = 0.006). The results of the present study indicate that ischemia used before each set even for a brief duration of <3 min, has positive effects on peak bar velocity at light loads, but it is insufficient to induce such effect on higher loads.

Acute Effects of Different Blood Flow Restriction Protocols on Bar Velocity During the Squat Exercise

The main goal of the present study was to evaluate the effects of different blood flow restriction (BFR) protocols (continuous and intermittent) on peak bar velocity (PV) and mean bar velocity (MV) during the squat exercise at progressive loads, from 40 to 90% 1RM. Eleven healthy men (age = 23.4 ± 3.1 years; body mass = 88.5 ± 12.1 kg; squat 1RM = 183.2 ± 30.7 kg; resistance training experience, 5.7 ± 3.6 years) performed experimental sessions once a week for 3 weeks in random and counterbalanced order: without BFR (NO-BFR), with intermittent BFR (I-BFR), and with continuous BFR (C-BFR). During the experimental session, the participants performed six sets of the barbell squat exercise with loads from 40 to 90% 1RM. In each set, they performed two repetitions. During the C-BFR session, the cuffs were maintained throughout the training session. During the I-BFR, the cuffs were used only during the exercise and released for each rest interval. The BFR pressure was set to ∼80% arterial occlusion pressure (AOP). Analyses of variance showed a statistically significant interaction for MV (p < 0.02; η² = 0.18). However, the post hoc analysis did not show significant differences between particular conditions for particular loads. There was no significant condition × load interaction for PV (p = 0.16; η² = 0.13). Furthermore, there were no main effects for conditions in MV (p = 0.38; η² = 0.09) as well as in PV (p = 0.94; η² = 0.01). The results indicate that the different BFR protocols used during lower body resistance exercises did not reduce peak bar velocity and mean bar velocity during the squat exercise performed with various loads.

Effects of Resting vs. Continuous Blood-Flow Restriction-Training on Strength, Fatigue Resistance, Muscle Thickness, and Perceived Discomfort

Introduction: The purpose of this study was to clarify whether blood-flow restriction during resting intervals [resting blood-flow restriction (rBFR)] is comparable to a continuous BFR (cBFR) training regarding its effects on maximum strength, hypertrophy, fatigue resistance, and perceived discomfort. Materials and Methods: Nineteen recreationally trained participants performed four sets (30-15-15-15 repetitions) with 20% 1RM on a 45° leg press twice a week for 6 weeks (cBFR, n = 10; rBFR, n = 9). Maximum strength, fatigue resistance, muscle thickness, and girth were assessed at three timepoints (pre, mid, and post). Subjective pain and perceived exertion were determined immediately after training at two timepoints (mid and post). Results: Maximum strength (p < 0.001), fatigue resistance (p < 0.001), muscle thickness (p < 0.001), and girth (p = 0.008) increased in both groups over time with no differences between groups (p > 0.05). During the intervention, the rBFR group exposed significantly lower perceived pain and exertion values compared to cBFR (p < 0.05). Discussion: Resting blood-flow restriction training led to similar gains in strength, fatigue resistance, and muscle hypertrophy as cBFR training while provoking less discomfort and perceived exertion in participants. In summary, rBFR training could provide a meaningful alternative to cBFR as this study showed similar functional and structural changes as well as less discomfort.

Acute Effects of Resistance Training with Blood Flow Restriction on Achilles Tendon Thickness

The Achilles tendon is one of the strongest and thickest tendons of the human body. Several studies have reported an immediate decrease in Achilles tendon thickness after a single bout of resistance training. However, the effects of blood flow restriction training on Achilles tendon thickness have not been investigated. The purpose of this study was to investigate the acute effects of different regimens of resistance training on Achilles tendon thickness. Fiftytwo participants (27.3 ± 7 years; 177.6 ± 11 cm; 72.2 ± 13.7 kg) were randomly allocated into one of the three groups: low-intensity exercise without (LI, n = 13) and with blood flow restriction (LI-BFR, n = 24), and high-intensity exercise (HI, n = 15). Participants from LI and LI-BFR groups performed four sets (1 x 30 + 3 x 15 reps) at 30% 1RM, while the HI group performed four sets (1 x 30 with 30% 1RM + 3 x 10 reps with 75% 1RM). All groups performed a plantar flexion exercise. For the LI-BFR group, a blood pressure cuff was placed on the dominant calf and inflated at 30% of the individual´s occlusion pressure (47.6 ± 19.8 mmHg). Sonographic images of Achilles tendon thickness were taken at pre, immediately after, 60 min and 24 h following acute bouts of exercise. Achilles tendon thickness was significantly reduced immediately after, 60 min and 24 h post-LI-BFR exercise (pre: 4.4 ± 0.4 mm vs. IA: 3.8 ± 0.4 mm vs. 60 min: 3.7 ± 0.3 mm vs. 24 h: 4.1 ± 0.3 mm; p < 0.001), whereas Achilles tendon thickness was unchanged for HI and LI groups (p > 0.05). These results suggest that blood flow restriction training may be an effective strategy to stimulate a positive response in Achilles tendon thickness.

Effects of Acute Caffeine Intake on Power Output and Movement Velocity During a Multiple-Set Bench Press Exercise Among Mild Caffeine Users

The main goal of this study was to evaluate the effectiveness of an acute dose of caffeine (6 mg/kg body mass (b.m.)) on power output and bar velocity during a bench press multiple-set resistance training session in participants with mild daily caffeine consumption (in the range of 1 to 3 mg/kg/b.m). Thirteen recreationally active male participants (age: 21.9 ± 1.2 years, body mass: 74.4 ± 5.3 kg, body mass index: 23.1 ± 1.6 kg/m2, bench press onerepetition maximum (1RM): 79.2 ± 14.9 kg), with daily caffeine ingestion of 1.56 ± 0.56 mg/kg/b.m., participated in the study with a randomized double-blind experimental design. Each participant performed two identical experimental sessions, 60 min after the intake of a placebo (PLAC) or 6 mg/kg/b.m. of caffeine (CAF-6). In each experimental session, participants performed 5 sets of 5 repetitions of the bench press exercise with a load equivalent to 70% 1RM. The eccentric and concentric phases of the bench press exercise were performed at maximal possible velocity in each repetition. Bar velocity was recorded with a linear position transducer and power output was calculated using velocity and load data. A two-way repeated measures ANOVA indicated no significant substance x set interaction for mean power output (MP), mean bar velocity (MV), peak power output (PP) and peak bar velocity (PV). However, there was a significant main effect of substance on MP (p < 0.01; η2 = 0.47) and MV (p < 0.01; η2 =0.45). Post hoc analysis for main effect revealed that MP and MV values in the CAF-6 group were higher than in the PLAC group in all 5 sets of the exercise (p < 0.05). In conclusion, this study demonstrated that an acute dose of caffeine before resistance exercise increased mean power output and mean bar velocity during a multiple-set bench press exercise protocol among mild caffeine users.

Impact of Ischemic Intra-Conditioning on Power Output and Bar Velocity of the Upper Limbs

This study evaluated the effects of ischemic conditioning on power output and bar velocity in the bench press exercise. Ten healthy males (age: 25 ± 2 years; body mass: 92 ± 8 kg; bench press one repetition maximum -1RM: 145 ± 13 kg), took part in two experimental sessions (with and without ischemia), 1 week apart in random and counterbalanced order. In the ischemic condition, cuffs placed around the upper part of the arms were inflated to 80% of arterial occlusion pressure before each set, while in the control condition there was no blood flow restriction. The exercise protocol included 5 sets of three repetitions each, against a resistance equal to 60% 1RM, with 5 min recovery intervals between sets. There was a main effect of condition for mean power output (MP) and mean bar velocity (MV) (p = 0.01), with overall MP being higher in ischemia than in control by 5.6 ± 4.1% (mean ± 90% compatibility limits), a standardized effect size (ES) of 0.51. Overall MV was also higher by 5.5 ± 4.0%, ES = 0.63. Peak power output (PP) and peak bar velocity (PV) were similar in set 1 of the control and ischemia condition (1039 ± 105 vs. 1054 ± 82 W; 684 ± 74 vs. 696 ± 53 W; 1.09 ± 0.07 vs. 1.12 ± 0.09 m/s; 0.81 ± 0.05 vs. 0.82 ± 0.05 m/s, p = 0.67 to 0.99, mean ± standard deviation). However, from set 3 onward (p = 0.03 to 0.001), PP and PV were higher in ischemia compared with control, with the highest difference observed in set 5 (10.9 ± 5.9%, ES = 0.73 for PP and 8.6 ± 4.6%; ES = 0.89 for PV). These results indicate that ischemia used before each set of the bench press exercise increases power output and bar velocity and this may be used as performance-enhancing stimulus during explosive resistance training.

Contrast Tempo of Movement and Its Effect on Power Output and Bar Velocity During Resistance Exercise

In this study, we examined the impact of contrast movement tempo (fast vs. slow) on power output and bar velocity during the bench press exercise. Ten healthy men (age = 26.9 ± 4.1 years; body mass = 90.5 ± 10.3 kg; bench press 1RM = 136.8 ± 27.7 kg) with significant experience in resistance training (9.4 ± 5.6 years) performed the bench press exercise under three conditions: with an explosive tempo of movement in each of three repetitions (E/E/E = explosive, explosive, explosive); with a slow tempo of movement in the first repetition and an explosive tempo in the next two repetitions (S/E/E = slow, explosive, explosive); and with a slow tempo of movement in the first two repetitions and an explosive tempo in the last repetition (S/S/E = slow, slow, explosive). The slow repetitions were performed with a 5/0/5/0 (eccentric/isometric/concentric/isometric) movement tempo, while the explosive repetitions were performed with an X/0/X/0 (X- maximal speed of movement) movement tempo. During each experimental session, the participants performed one set of three repetitions at 60%1RM. The two-way repeated measures ANOVA showed a statistically significant interaction effect for peak power output (PP; p = 0.03; η² = 0.26) and for peak bar velocity (PV; p = 0.04; η² = 0.24). Futhermore there was a statistically significant main effect of condition for PP (p = 0.04; η² = 0.30) and PV (p = 0.02; η² = 0.35). The post hoc analysis for interaction revealed that PP was significantly higher in the 2nd and 3rd repetition for E/E/E compared with the S/S/E (p < 0.01 for both) and significantly higher in the 2nd repetition for the S/E/E compared with S/S/E (p < 0.01). The post hoc analysis for interaction revealed that PV was significantly higher in the 2nd and 3rd repetition for E/E/E compared with the S/S/E (p < 0.01 for both), and significantly higher in the 2nd repetition for the S/E/E compared with the S/S/E (p < 0.01). The post hoc analysis for main effect of condition revealed that PP and PV was significantly higher for the E/E/E compared to the S/S/E (p = 0.04; p = 0.02; respectively). The main finding of this study was that different distribution of movement tempo during a set has a significant impact on power output and bar velocity in the bench press exercise at 60%1RM. However, the use of one slow repetition at the beginning of a set does not decrease the level of power output in the third repetition of that set.

Acute Effects of Continuous and Intermittent Blood Flow Restriction on Movement Velocity During Bench Press Exercise Against Different Loads

This study evaluated the effects of continuous and intermittent blood flow restriction (BFR) with 70% of full arterial occlusion pressure on bar velocity during the bench press exercise against a wide range of resistive loads. Eleven strength-trained males (age: 23.5 ± 1.4 years; resistance training experience: 2.8 ± 0.8 years, maximal bench press strength - 1RM = 101.8 ± 13.9 kg; body mass = 79.8 ± 10.4 kg), performed three different testing protocols in random and counterbalanced order: without BFR (NO-BFR); intermittent BFR (I-BFR) and continuous BFR (C-BFR). During each experimental session, subjects performed eight sets of two repetitions each, with increasing loads from 20 to 90% 1RM (10% steps), and 3 min rest between each set. In the C-BFR condition occlusion was kept throughout the trial, while in the I-BFR, occlusion was released during each 3 min rest interval. Peak bar velocity (PV) during the bench press exercise was higher by 12-17% in both I-BFR and C-BFR compared with NO-BFR only at the loads of 20, 30, 40, and 50% 1RM (p < 0.001), while performance at higher loads remained unchanged. Mean bar velocity (MV) was unaffected by occlusion (p = 0.342). These results indicate that BFR during bench press exercise increases PV and this may be used as an enhanced stimulus during explosive resistance training. At higher workloads, bench press performance was not negatively affected by BFR, indicating that the benefits of exercise under occlusion can be obtained while explosive performance is not impaired.

The influence of compressive gear on maximal load lifted in competitive powerlifting

The competition in powerlifting has been divided into two divisions, with gear equipment (EQ) and without gear equipment (RAW). When competing in the EQ division, additional supportive gear can be worn by the athletes, while in the RAW division such gear is not allowed. The aim of the study was to compare the results of the RAW and EQ powerlifting divisions based on the results of world championships and current world records. One-hundred and twenty powerlifters (63 men, 57 women) were included to the analysis. Post hoc analysis for the results of men’s world championships indicated significantly higher results of the barbell squat (SQ; p < 0.001; ES = 1.31), bench press (BP; p < 0.001; ES = 1.27) and deadlift (DL; p < 0.001; ES = 0.37) for EQ compared to the RAW division. Post hoc analysis for the results of women’s world championships indicated significantly higher results of the SQ (p < 0.001; ES = 1.31), BP (p < 0.001; ES = 1.13) and DL (p < 0.001; ES = 0.71) for the EQ compared to the RAW division. Post hoc analysis for men’s world record indicated significantly higher results in the SQ (p < 0.001; ES = 1.32) and BP (p < 0.001; ES = 1.24) for the EQ compared to the RAW division. Furthermore, there were no significant differences in the results of world records in the DL (p = 0.901; ES = 0.26) between the EQ and RAW divisions. Post hoc analysis for women’s world records indicated significantly higher results in the SQ (p < 0.001; ES = 1.22) and BP (p < 0.001; ES = 1.99) for the EQ compared to RAW division. The main finding of the study was that supportive gear increases maximal load lifted during powerlifting competition.

Does Acute Blood Flow Restriction with Pneumatic and Non-Pneumatic Non-Elastic Cuffs Promote Similar Responses in Blood Lactate, Growth Hormone, and Peptide Hormone?

Blood flow restriction (BFR) can be used during resistance training (RT) through pressure application with pneumatic (pressurized) cuffs (PC) or non-pneumatic (practical) cuffs (NPC). However, PC are expensive and difficult to use in the gym environment compared to NPC. The main aim was to compare, correlate, and verify the hormonal and metabolic responses between PC and NPC during a low-load BFR during RT of the upper-body. The secondary aim was to compare blood lactate (BLa) concentration between pre- and post-exercise (2-min into recovery), as well as growth hormone (GH) and insulin-like growth factor 1 (IGF-1) concentration before, 10-min, and 15-min post exercise. Sixteen trained men randomly and alternately completed two experimental RT protocols of the upper-body : A) RT with BFR at 20% 1RM using PC (RT-BFR-PC) and (B) RT with BFR at 20% 1RM using NPC (RT-BFR-NPC) in the bench press, wide-grip lat pulldown, shoulder press, triceps pushdown, and biceps curl exercises. There was no significant difference in BLa 2-min post exercise (p=0.524), GH 10-min (p=0.843) and 15-min post exercise (p=0.672), and IGF-1 10-min (p=0.298) and 15-min post exercise (p=0.201) between RT-BFR-PC and RT-BFR-NPC. In addition, there was a moderate correlation, satisfactory ICCs, and agreement between both protocols in metabolic and hormonal responses. The experimental sessions promoted significant increases in GH and BLa, but not in IGF-1 (p<0.05). The absence of a significant difference between RT-BFR-PC and RT-BFR-NPC in metabolic and hormonal responses highlight the applicability of NPC as a low-cost and easy-to-use tool for BFR upper-body RT.

The Acute Impact of External Compression on Back Squat Performance in Competitive Athletes

The aim of the present study was to evaluate the effects of external compression with blood flow restriction on power output and bar velocity changes during the back-squat exercise (SQ). The study included 10 judo athletes (age = 28.4 ± 5.8 years; body mass = 81.3 ± 13.1 kg; SQ one-repetition maximum (1-RM) 152 ± 34 kg; training experience 10.7 ± 2.3 years).

METHODS

The experiment was performed following a randomized crossover design, where each participant performed three different exercise protocols: (1) control, without external compression (CONT); (2) intermittent external compression with pressure of 100% arterial occlusion pressure (AOP) (EC-100); and (3) intermittent external compression with pressure of 150% AOP (EC-150). To assess the differences between conditions, the participants performed 3 sets of 3 repetitions of the SQ at 70% 1-RM. The differences in peak power output (PP), mean power output (MP), peak bar velocity (PV), and mean bar velocity (MV) between the three conditions were examined using repeated measures two-way ANOVA.

RESULTS

The post hoc analysis for the main effect of conditions showed a significant increase in PP (p = 0.03), PV (p = 0.02), MP (p = 0.04), and MV (p = 0.03), for the EC-150, compared to the CONT. Furthermore, a statistically significant increase in PP (p = 0.04), PV (p = 0.03), MP (p = 0.02), and MV (p = 0.01) were observed for the EC-150 compared to EC-100. There were no significant changes in PP, PV, MP, and MV, between EC-100 and CONT conditions.

CONCLUSION

The results indicate that the use of extremely high-pressure external compression (150% AOP) during high-loaded (70% 1-RM) lower limb resistance exercise elicits an acute increase in power output and bar velocity.

The Acute Effects of External Compression With Blood Flow Restriction on Maximal Strength and Strength-Endurance Performance of the Upper Limbs

The main goal of the present study was to evaluate the acute effects external compression with blood flow restriction (BFR) at 100 and 150% of full arterial occlusion pressure (AOP) on maximal strength and strength-endurance performance during the bench press (BP) exercise. The study included 12 strength-trained male subjects (age = 23.2 ± 2.66 years; body mass = 75.3 ± 6.33 kg; height = 179.1 ± 3.82 cm), experienced in resistance training (5.7 ± 2.93 years). During the experimental sessions in a randomized crossover design, the subjects performed a 1 repetition maximum (1RM) test and three sets of the BP using 60% 1RM to failure with three different conditions: without BFR (NO-BFR); BFR with a pressure of 100% AOP (BFR₁₀₀); and BFR with a pressure of 150% AOP (BFR₁₅₀). The differences between the NO-BFR, BFR₁₀₀, and BFR₁₅₀ conditions were examined using repeated measures ANOVA. The ANOVA indicated significant main effect for condition in 1RM, number of performed repetitions (REP), and time under tension (TUT) (p < 0.01). Post hoc analyses for the main effect indicated significant increases in 1RM (p < 0.01; 95.00 ± 15.37 vs 91.87 ± 15.99), REP (p < 0.01; 17.56 ± 3.36 vs 15.67 ± 5.24), and TUT (p < 0.01; 32.89 ± 6.40 vs 28.72 ± 6.18) for the BFR₁₅₀ condition compared to NO-BFR. Furthermore, significant increases in REP (p = 0.03; 17.56 ± 3.36 vs 16.47 ± 4.01) and TUT (p = 0.03; 32.89 ± 6.40 vs 30.00 ± 6.45) were observed for the BFR₁₅₀ condition compared to the BFR₁₀₀. The results of the present study indicate that high external compression increases maximal strength evaluated by the 1RM test, as well as endurance performance during three sets of the BP exercise.

Does Post-Activation Performance Enhancement Occur During the Bench Press Exercise under Blood Flow Restriction?

Background: The aim of the present study was to evaluate the effects of post-activation performance enhancement (PAPE) during successive sets of the bench press (BP) exercise under blood flow restriction (BFR). Methods: The study included 10 strength-trained males (age = 29.8 ± 4.6 years; body mass = 94.3 ± 3.6 kg; BP 1-repetition maximum (1RM) = 168.5 ± 26.4 kg). The experiment was performed following a randomized crossover design, where each participant performed two different exercise protocols: under blood flow restriction (BFR) and control test protocol (CONT) without blood flow restriction. During the experimental sessions, the study participants performed 3 sets of 3 repetitions of the BP exercise at 70%1RM with a 5 min rest interval between sets. The differences in peak power output (PP), mean power output (MP), peak bar velocity (PV), and mean bar velocity (MV) between the CONT and BFR conditions were examined using 2-way (condition × set) repeated measures ANOVA. Furthermore, t-test comparisons between conditions were made for the set 2-set 1, set 3-set 1, and set 3-set 2 delta values for all variables. Results: The post hoc results for condition × set interaction in PP showed a significant increase in set 2 compared to set 1 for BFR (p < 0.01) and CONT (p = 0.01) conditions, a significant increase in set 3 compared to set 1 for the CONT (p = 0.01) condition, as well as a significant decrease in set 3 compared to set 1 for BFR condition occurred (p < 0.01). The post hoc results for condition × set interaction in PV showed a significant increase in set 2 compared to set 1 for BFR (p < 0.01) and CONT (p = 0.01) conditions, a significant increase in set 3 compared to set 1 for CONT (p = 0.03) condition, as well as a significant decrease in set 3 compared to set 1 for BFR condition (p < 0.01). The t-test comparisons showed significant differences in PP (p < 0.01) and PV (p = 0.01) for set 3-set 2 delta values between BFR and CONT conditions. Conclusion: The PAPE effect was analyzed through changes in power output and bar velocity that occurred under both the CONT and BFR conditions. However, the effects of PAPE have different kinetics in successive sets for BFR and for CONT conditions.