Does Blood Flow Restriction Therapy in Patients Older Than Age 50 Result in Muscle Hypertrophy, Increased Strength, or Greater Physical Function? A Systematic Review

Abstract

Background Blood flow restriction (BFR) is a process of using inflatable cuffs to create vascular occlusion within a limb during exercise. The technique can stimulate muscle hypertrophy and improve physical function; however, most of these studies have enrolled healthy, young men with a focus on athletic performance. Furthermore, much of the information on BFR comes from studies with small samples sizes, limited follow-up time, and varied research designs resulting in greater design, selection, and sampling bias. Despite these limitations, BFR’s popularity is increasing as a clinical rehabilitation tool for aging patients. It is important for practitioners to have a clear understanding of the reported effects of BFR specifically in older adults while simultaneously critically evaluating the available literature before deciding to employ the technique. Questions/purposes (1) Does BFR induce skeletal muscle hypertrophy in adults older than 50 years of age? (2) Does BFR improve muscle strength and/or physical function in adults older than 50 years? Methods Using PubMed, Google Scholar, Web of Science, and Science Direct, we conducted a systematic review of articles using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to assess the reported effects of BFR on skeletal muscle in older adults. Included articles enrolled participants 50 years of age or older and used BFR in conjunction with exercise to study the effects of BFR on musculoskeletal outcomes and functionality. The following search terms were used: “blood flow restriction” OR “KAATSU” OR “ischemic training” AND “clinical” AND “elderly.” After duplicates were removed, 1574 articles were reviewed for eligibility, and 30 articles were retained with interventions duration ranging from cross-sectional to 16 weeks. Sample sizes ranged from 6 to 56 participants, and exercise tasks included passive mobilization or electrical stimulation; walking; resistance training using machines, free weights, body weight, or elastic bands; and water-based activities. Furthermore, healthy participants and those with cardiovascular disease, osteoarthritis, osteoporosis, sporadic inclusion body myositis, spinal cord injuries, and current coma patients were studied. Lastly, retained articles were assigned a risk of bias score using aspects of the Risk of Bias in Nonrandomized Studies of Interventions and the Cochrane Collaboration’s tool for assessing the risk of bias in randomized trials. Results BFR, in combination with a variety of exercises, was found to result in muscle hypertrophy as measured by muscle cross-sectional area, thickness, volume, mass, or circumference. Effect sizes for BFR’s ability to induce muscle hypertrophy were calculated for 16 of the 30 papers and averaged 0.75. BFR was also shown to improve muscle strength and functional performance. Effect sizes were calculated for 21 of the 30 papers averaging 1.15. Conclusions Available evidence suggests BFR may demonstrate utility in aiding rehabilitation efforts in adults older than 50 years of age, especially for inducing muscle hypertrophy, combating muscle atrophy, increasing muscle strength, and improving muscle function. However, most studies in this systematic review were at moderate or high risk of bias; that being so, the findings in this systematic review should be confirmed, ideally using greater sample sizes, randomization of participants, and extended follow-up durations. Level of Evidence Level II, systematic review.

Low-Intensity Resistance Training with Moderate Blood Flow Restriction Appears Safe and Increases Skeletal Muscle Strength and Size in Cardiovascular Surgery Patients: A Pilot Study

“…The novel moderate blood flow restriction (KAATSU) training moderately restricts blood flow by compressing the proximal portion of the lower or upper extremities with a specially-designed cuff. It is a well-established method to increase muscle strength and size in athletes and healthy subjects through short-term low-intensity RT (20–30% of 1-RM) [ 12 , 13 , 14 , 15 , 16 ]. The mechanisms by which KAATSU training potentiates the effects of low-intensity RT remain unclear, but appear to be related, in part, to an increase in muscle activation [ 12 , 17 , 18 , 19 ].…”

“…[ 21 , 22 , 23 ]. Until now, KAATSU RT has been used without adverse side effects in the physical rehabilitation of older adults [ 16 ], in patients recovering from an anterior cruciate ligament (ACL) surgery [ 24 ], and in patients with ischemic heart disease [ 25 ]. Thus, KAATSU RT has the potential to be an effective method to improve muscle strength and size in patients with cardiac surgery.…”

Blood Flow Restriction Training

“…6,7,20 Outcomes regarding decreased pain have also been shown to occur in individuals with patellofemoral or anterior knee pain 49,50 as well as patellar tendinopathy. 51 While most studies tend to focus on physiological outcomes such as hypertrophy, strength, and reduced atrophy, 52 there is emerging evidence that BFR can improve outcomes related to function and pain.…”

Postoperative Management for Articular Cartilage Surgery in the Knee

“…18 Due to the restrictive nature of postoperative rehabilitation after cartilage surgery, patients typically have a noticeable loss in strength, which is especially therapy is a modality that can be safely used to address muscle atrophy during the periods of recovery when strengthening loads must be avoided. 19,20 With traditional strength training, repeatedly performing an exercise between 60 and 70% of the individual's one-repetition maximum is required for muscle hypertrophy. However, with BFR (►Fig.…”

“…Phase III: Remodeling and Maturation (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26) The emphasis during the third phase of recovery after OAT is the continued progression of strength, endurance, and neuromuscular control. Patients are progressed through closed chain exercises with a gradual increase from 60 to 90 degree depth for squats and lunges.…”