Blood flow restriction in human skeletal muscle during rest periods after high-load resistance training down-regulates miR-206 and induces Pax7

Backgroud:Blood flow re striction(BFR) with low-intensity re sistance training has been shown to result in hypertrophy of skeletal muscle.In this study,we tested the hypothesis that BFR during the rest periods between acute,high-intensity resistance exercise sessions(70% of 1 repetition maximum,7 sets with 10 repetitions) enhances the effects of the resistance training.Methods:A total of 7 healthy young men performed squats,and between sets BFR was carried out on one leg while the other leg served as a control.Because BFR was applied during rest periods,even severe occlusion pressure(approximately 230 mmHg),which almost completely blocked blood flow,was well-tolerated by the participants.Five muscle-specific microRNAs were measured from the biopsy samples,which were taken 2 h after the acute training.Results:Doppler data showed that the pattern of blood flow recovery changed significantly between the first and last BFR.microRNA-206 levels significantly decreased in the BFR leg compared to the control.The mRNA levels of RAC-β serine/threonine-protein kinase v22,nuclear re spiratory factor 1,vascular endothelial growth factor,lupus Ku autoantigen protein p70 genes(p <0.05),and paired box 7(p <0.01) increased in the BFR leg.The protein levels of paired box 7,nuclear respiratory factor 1,and peroxisome proliferator-activated receptor y coactivator 1α did not differ between the BFR leg and the control leg.Conclusion:BFR,during the rest periods of high-load resistance training,could lead to mRNA elevation of those proteins that regulate angiogenesis,mitochondrial biogenesis,and muscle hypertrophy and repair.However,BFR also can cause DNA damage,judging from the increase in mRNA levels of lupus Ku autoantigen protein p70.

Blood flow restriction training improves the efficacy of routine intervention in patients with chronic ankle instability

As a new means of rehabilitation,blood flow restriction training(BFRT)is widely used in the field of musculoskeletal rehabilitation.To observe whether BFRT can improve the efficacy of routine rehabilitation intervention in patients with chronic ankle instability(CAI).Twenty-three patients with CAI were randomly divided into a routine rehabilitation group(RR Group)and a routine rehabilitationþblood flow restriction training group(RRþBFRT Group)according to the Cumberland Ankle Instability Tool(CAIT)score.The RR Group was treated with routine rehabilitation means for intervention,and the RRþBFRT Group was treated with a tourniquet to restrict lower limb blood flow for rehabilitation training based on routine training.Before and after the intervention,the CAIT score on the affected side,standing time on one leg with eyes closed,comprehensive scores of the Y-balance test,and surface electromyography data of tibialis anterior(TA)and peroneus longus(PL)were collected to evaluate the recovery of the subjects.Patients were followed up 1 year after the intervention.After 4 weeks of intervention,the RRþBFRT Group CAIT score was significantly higher than the RR Group(19.33 VS 16.73,p<0.05),the time of standing on one leg with eyes closed and the comprehensive score of Y-balance were improved,but there was no statistical difference between groups(p>0.05).RRþBFRT Group increased the muscle activation of the TA with maximum exertion of the ankle dorsal extensor(p<0.05)and had no significant change in the muscle activation of the PL with maximum exertion of the ankle valgus(p>0.05).There was no significant difference in the incidence of resprains within 1 year between the groups(36.36%VS 16.67%,p>0.05).The incidence of ankle pain in the RRþBFRT Group was lower than that in the RR Group(63.64%VS 9.09%,p<0.01).Therefore,four-weeks BFRT improves the effect of the routine intervention,and BFRT-related interventions are recommended for CAI patients with severe ankle muscle mass impairment or severe pain.

Comparison of blood flow restriction training and conventional resistance training for the improvement of sarcopenia in the older adults:A systematic review and meta-analysis

Age-related sarcopenia places a tremendous burden on healthcare providers and patients'families.Blood flow restriction(BFR)training may be a promising treatment to bring sarcopenia down,and it offers numerous advantages over traditional resistance training.The purpose of this review was to compare the effects of BFR training and conventional resistance training on clinically delayed sarcopenia in the elderly.Databases such as PubMed,Web of Science,Embase,and Science Direct were searched to identify eligible studies;blinded data extraction was performed to assess study quality,and conflicts were submitted to third parties.Someone made the decision.One author used Review Manager(RevMan)5.4 and compared it with data obtained by another author for this purpose.A total of 14 studies met the inclusion criteria for this review.The funnel plots of the studies did not show any substantial publication bias.Low-load blood flow restriction(LL-BFR)had no significant effect on muscle mass compared with high-load resistance training(HL-RT)(p=0.74,SMD=0.07,95%CI:0.33 to 0.46)and LL-BFR had a significant effect on muscle strength compared with HL-RT(p=0.03,Z=2.16,SMD=-0.34,95%CI:0.65 to-0.03).LL-BFR showed a slight effect on mass compared to LL-RT(p=0.26,SMD=0.25,95%CI:0.19 to 0.69).Sensitivity analysis produced a nonsignificant change,suggesting that the results of this study are reasonable.In conclusion,the data suggest the possibility that BFR training improves age-related sarcopenia.

Chronic hemodynamic adaptations induced by resistance training with and without blood flow restriction in adults:A systematic review and meta-analysis

The purposes of this systematic review and meta-analysis of peer-reviewed literature were to examine the chronic effects of resistance training with blood flow restriction(RT-BFR)on hemodynamics,and to compare these adaptations to those induced by traditional resistance training(TRT)programs in adults(PROSPERO:Registry:CRD42022339510).A literature search was conducted across PubMed,Sports Discus,Scielo,and Web of Science databases.Two independent reviewers extracted study characteristics and blood pressure measures.Risk of bias(The Cochrane risk of bias tool for randomized controlled trials[RoB-2]),and the certainty of the evidence(Grading of Recommendations,Assessment,Development,and Evaluation[GRADE])were used.A total of eight studies met the inclusion criteria for systolic(SBP),diastolic(DBP),and mean arterial pressure(MAP).Regarding the comparison of RT-BFR vs.non-exercise,no significant differences favoring the exercise group were observed(p>0.05).However,when compared to TRT,RT-BFR elicited additional improvements on DBP(-3.35;95%CI-6.00 to-0.71;I^(2)=14%;z=-2.48,p=0.01),and on MAP(-3.96;95%CI-7.94 to 0.02;I^(2)=43%;z=-1.95,p=0.05).Results indicate that RT-BFR may elicit a decrease in DBP in comparison with TRT,but the lack of data addressing this topic makes any conclusion speculative.Future research on this topic is warranted.

Blood flow restriction during the resting periods of high-intensity resistance training does not alter performance but decreases MIR-1 and MIR-133A levels in human skeletal muscle

Blood flow restriction(BFR)during exercise bouts has been used to induce hypertrophy of skeletal muscle,even with low loads.However,the effects of BFR during the rest periods between sets are not known.We have tested the hypothesis that BFR during rest periods between sets of high-intensity resistance training would enhance performance.Twenty-two young adult male university students were recruited for the current study,with n=11 assigned to BFR and n=11 to a control group.The results revealed that four weeks training at 70%of 1 RM,five sets and 10 repetitions,three times a week with and without BFR,resulted in similar progress in maximal strength and in the number of maximal repetitions.The miR-1 and miR-133a decreased significantly in the vastus lateralis muscle of BFR group compared to the group without BFR,while no significant differences in the levels of miR133b,miR206,miR486,and miR499 were found between groups.In conclusion,it seems that BFR restrictions during rest periods of high-intensity resistance training,do not provide benefit for enhanced performance after a four-week training program.However,BFR-induced downregulation of miR-1 and miR-133a might cause different adaptive responses of skeletal muscle to high intensity resistance training.

Time to consider the potential role of alternative resistance training methods in cancer management?

Exercise has emerged as fundamental therapeutic medicine in the management of cancer.Exercise improves health-related outcomes,including quality of life,neuromuscular strength,physical function,and body composition,and it is associated with a lower risk of disease recurrence and increased survival.Moreover,exercise during or post cancer treatments is safe,can ameliorate treatment-related side effects,and may enhance the effectiveness of chemotherapy and radiation therapy.To date,traditional resistance training(RT)is the most used RT modality in exercise oncology.However,alternative training modes,such as eccentric,cluster set,and blood flow restriction are gaining increased attention.These training modalities have been extensively investigated in both athletic and clinical populations(e.g.,age-related frailty,cardiovascular disease,type 2 diabetes),showing considerable benefits in terms of neuromuscular strength,hypertrophy,body composition,and physical function.However,these training modes have only been partially or not at all investigated in cancer populations.Thus,this study outlines the benefits of these alternative RT methods in patients with cancer.Where evidence in cancer populations is sparse,we provide a robust rationale for the possible implementation of certain RT methods that have shown positive results in other clinical populations.Finally,we provide clinical insights for research that may guide future RT investigations in patients with cancer and suggest clear practical applications for targeted cancer populations and related benefits.

Relationship Between the Restricted AKNS Flows and the Restricted KdV Flows

It is well-known that every member of the KdV hierarchy of equations can be obtained from the AKNS hierarchy of equations by imposing a simple reduction. The author finds that the reduction conditions of the potentials in the spectral problem can be replaced by adding additional eigenfunction equations to the spectral problem, and then shows that the restricted KdV flows, such as the Neumann system, the Gamier system and the generalized multicomponent Henon-Hieles system, are a kind of special reductions of the restricted AKNS flows.

A Bcklund Transformation of the Restricted mKdV Flow with a Rosochatius Deformation

A Bcklund transformation of the restricted mKdV flow with a Rosochatius deformation is constructed.Its Lax representation and thus N invariants in involution are presented.Such Bcklund transformation is a Rosochatius deformation of that of the restricted mKdV flow.

RESTRICTED FLOWS OF A HIERARCHYOF INTEGRABLE DISCRETE SYSTEMS

The restricted flows of a hierarchy of discrete integrable systems are presented. It is shownthat integrals of motion and Lax representation for restricted flows as well as a discrete zerocurvature representation for the hierarchy with sources can be deduced from the zero-curvaturerepresentation for the hierarchy. Also it is studied how the hierarchy is related to the AKNShierarchy in the continuous limit.