Blood Flow Restriction Training
Blood Flow Restriction (BFR) training has been around since its inception in 1996. However, in its earlier years, the strategy was seen as taboo, dangerous, or unfounded. Ongoing research has proven and continues to prove the effectiveness of BFR in a multitude of populations. The fitness industry has adapted the practice for those high-level competitors seeking to wring out every bit of hypertrophy possible. Rehabilitation professionals are pushing protocols for the implementation of BFR in post-surgery and injured populations. Strength coaches implement this style of training for in season athletes due to its low impact nature. BFR’s uses cover the entire spectrum of physical performance, across all ages and interests. This discussion today will focus on providing a scientific explanation and analysis of hypothesized mechanisms of action, as well as physiological responses to BFR. In addition, I will cover specific protocols and contra-indications to its use.
Physiological Responses to BFR
-Increased pressure on proximal attachment of muscle via band/strap/cuff
-Restricts Venous Blood Flow in the muscles (Intramuscular blood pooling)
-↓ in muscle O2, lactic acid clearance, metabolic product build up (stress)
-↑ number of motor units recruited to maintain strength (fast twitch fiber recruitment)
-↑ release of growth hormone as well as intramuscular growth factors (intramuscular anabolic signaling)
-↑ Muscular Strength, Power, and Hypertrophy; ↑ bone density
-Takarada et al
-14% increase in knee extensor strength when training at 50% of 1RM with BFR compared to resistance training alone.
-Yamanka et al
-Division I A football players training at 20% of 1RM with 30-20-20-20 rep scheme for bench press and squat
-BFR group showed 1RM increases for bench press (+7.0%) and squat(+8.0%)
-Luebbers et al
-American football players; trained 4 days/week for 7 total weeks
-High load training combined with low load BFR demonstrated greatest increases in squat (increase 1 RM by 24.9 Kg compared to 6.0-14.1 kg in other groups)
-Takarada et al
-BFR with bilateral knee extension; 5 sets to failure; growth hormone concentrations increased 290x greater than baseline
-Markers of muscle damage were not different between BFR and non BFR groups
-“However, Neural stimulus is much different than high load training for athletes.”
-47 studies revealing the BFR group having .4 Nm greater strength gain than controls
-Increases in Hypertrophy ranged 2-5 cm
Concluded: “low load resistance training (20-30%) when combined with BFR caused an exaggerated response for maximizing muscle strength and hypertrophy.”
Practical (Non-Clinical) Implementation
· Compression Wraps
· Elastic knee/wrist/elbow wraps
· 6-7/10 tightness
· No numbness, tingling, pain
· Rep Scheme
· 4 Sets
· Reps of 30/15/15/15
· Mixture of failure and sub-maximal training
Individuals with cardiovascular diseases including but not limited to DVT, atrial fibrilation, and varicose veins - or those aged greater than 58 should abstain from implementing BFR training without a medical professionals consent. All individuals should consult with a health care provider before implementing any vigorous training regiment to assess for possible health risks.
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