Blood Flow Restriction Basics: What You Need To Know
by Nicholas Rolnick, PT, DPT, MS, CSCS
The Importance of Strength and Muscle Mass
Strength and muscle mass are extremely important to longevity and sports performance. Studies have shown that the amount of fat-free mass (which includes your muscles as well as other non-fat structures like bone) is a predictor of all-cause morbidity (disease) and mortality (death!). Increasing and/or maintaining a high level of muscle tissue is beneficial for overall health. Higher levels of muscle mass also closely correlate to higher levels of strength and athletic performance, highlighting the importance of muscle mass for both health and performance purposes.
Traditional resistance-training guidelines for gaining strength and muscle mass involve lifting weights greater than 70% of the 1-rep maximum. For example, if an individual’s maximum bench press is 100 lbs, in order to improve strength and muscle mass of the arms and chest, these guidelines would suggest lifting at 70 lbs or greater during workouts.
Blood Flow Restriction Training
Blood flow restriction (BFR) training is a new therapy tool that has been proven safe and beneficial for optimizing muscle mass and strength. BFR involves application of a cuff-like tourniquet placed over the closest part of the arm or leg (see pictures below).
The tourniquet is inflated prior to the start of treatment, reducing the ability of blood to be pumped back to your heart from the occluded limb. This creates temporary increases in oxygen demand for the muscles for the duration of the treatment. The increased demand for oxygen means that muscles have to work harder than they normally would in order to produce a muscle contraction. This stresses the muscle at weights where it normally would not be stimulated (between 20-35% of the 1-repetition maximum, or 20-35 pounds in the bench press example). Most people see benefits without using any weights at all!
The machine is for all intents and purposes, a computer that constantly monitors the amount of pressure it applies to the body, keeping it the same the entire time of the treatment (something other tools that do BFR do not do!). The pressure applied to the leg by the machine is illustrated by the number “199” in the image above. The number will vary based on the size of the limb. In my case, the number is higher due to my thigh size. If the same measurement was taken on my arm, the value would be much lower. How this all happens is through the portal on the front of the machine (the circled area) that serves as the connection between the machine and the cuff allowing air to be pressurized.
Using Blood Flow Restriction Training
While the cuff is being inflated, individuals should feel some tightness around the arm/thigh as the machine calibrates the specific pressures needed for the treatment. After a short calibration period, the therapist will configure the appropriate settings based on the goals of treatment.
Anyone using BFR should never feel pain, numbness or tingling during or after exercise. BFR does create an environment where the muscles have to work hard, so that “muscle burn” is expected. In fact, that’s how the muscles are getting bigger and stronger! The above picture is my “BFR face” during the last set of 10 pound bicep curls! The “muscle burn” is real!
Typical amount of sets and repetitions for an exercise with BFR include a first set of 30 repetitions (to create that “muscle burn” effect) followed by 3 sets of 15 repetitions (total of 75 repetitions for the entire exercise). Each inter-set rest period is about 30 seconds. The machine keeps the pressure consistent throughout the duration of the rest periods, preventing any of the blood from escaping the muscle. This can be slightly uncomfortable.
Following completion of the exercise, the therapist will deflate the cuff.
Let me tell you – it feels amazing afterwards! I’ve had many people tell me that it feels like a great massage to the arm or leg and that they feel that the arm/leg feels “looser” and that it had a “good workout.” These are what I like to call the rewards for working hard! Not to mention, the muscle mass and strength gains to come!
Some people may experience some soreness 24-48 hours after the exercise. This is normal and if it occurs, will likely be similar to what it feels after exercising a new muscle for the first time in awhile. I must say though, that in my experience with this training tool, less than half of people report being sore at all!
Who Can Use BFR?
I will touch upon these individually in greater detail in upcoming posts, but here are some examples of when BFR can help:
Post-surgery (day 3-day 14) – when weightbearing or actively moving the muscle is difficult, use of BFR with passive range of motion can help in preservation of muscle mass and strength and facilitate a quicker return to function and sport.
Post-surgery (day 14+) – active range of motion with the surgical arm/leg can promote muscle mass and strength increases of the surgical region as well as other muscles located before and after the application of the cuff
Elderly – strength training in a safe manner to improve function and reduce fall risk.
Athletes – in-season maintenance of muscle mass and strength
General Fitness – adding BFR to heavy load training can ensure muscle fatigue and help improve strength and muscle mass outcomes; it can also be used as a de-load week to give joints a break while continuing to promote increases in muscle mass and strength.
Improving Aerobic Endurance – BFR has been shown to improve aerobic endurance capacity at lower intensities than ever thought possible in shorter amounts of time compared to traditional low intensity (for example – jogging) training.
Improving Bone Density – there is evidence suggesting that BFR can stimulate bone growth in a walking or resistance-training program.
Individuals with Neuromuscular Conditions – because there is minimal to no muscle damage occurring with BFR, populations with conditions such as Inclusion Body Myositis or Duchenne Muscular Dystrophy can use BFR to help improve their function.
Individuals with Shoulder, Hip and Knee Osteoarthritis – the low loading and high muscle activation create positive strength and muscle mass adaptations in these populations, important for long-term health and potentially reducing the need for surgery.
SHORT VIDEOS THAT EXPLAIN BFR:
1. Overview of Blood Flow Restriction Training
2. Safety of Blood Flow Restriction Training
3. Mechanisms of Blood Flow Restriction Training
About the Author:
Nicholas Rolnick, PT, DPT, MS, CSCS is a physical therapist practicing in New York City. He graduated with a Doctorate of Physical Therapy from Columbia University and has a Masters of Science in Health Promotion Management. Nick States: I amfascinated by the human body, its unlimited potential, and its amazing ability to recover from injury. The human body is like a machine. Machines are most efficient and effective when they are in balance. When a machine is out of balance, it takes a skilled mechanic to diagnose the imbalance and provide the remedy. As a physical therapist, I see myself as a “human performance mechanic.” My goal is to keep my patients in perfect balance, have the skills to recognize asymmetries and help my patients enjoy the benefits of pain-free movement.
Find him Exclusively for patient care and personal training at: PHlex NYC at 370 Lexington Avenue, Floor 23 New York, NY 10017