Training Tips

Blood Flow Restriction Training – What Trainers Need to Know

Blood Flow Restriction Training – What Trainers Need to Know

If you have seen people at the gym wearing tight bands around their arms or legs, you probably wondered what they were hoping to achieve. The answer is bigger, stronger muscles.

Blood flow restriction (BFR) training is not new, but it is becoming increasingly popular in gyms. Expect your clients to start asking you about it and whether they should be using it. 

There can be some great benefits to adding this to a client’s training. But there are also risks. You need to know how to do this right, and be aware that some people should not use BFR at all. 

Blood Flow Restriction Training, or Occlusion Training – What is It? 

Blood flow restriction training, also known as occlusion training, is a strategy for developing muscle mass and strength with lighter weights. It involves using a tourniquet to restrict blood flow to certain parts of the body. 

If you’re not sure what a tourniquet is, think of when you give blood or a nurse takes a blood sample at your doctor’s office. They wrap a tight band around your arm before drawing blood from a vein. This physically restricts blood flow to the arm below the band or tourniquet. 

We build muscle strength and muscle hypertrophy by using strength loads and reps that lead to fatigue. When the muscles get fatigued, they are oxygen-depleted. This is the condition under which growth occurs. To get there you need relatively heavy weights and a significant number of reps. 

With BFR, these conditions can be met more easily. The bands restrict blood flow. Along with resistance or strength training, this restriction creates the oxygen-depleted environment needed for muscle growth. 

Do you know if your clients want to be stronger or to have bigger muscles? It’s an important distinction that informs your training plans. This ISSA blog will help you understand the differences between muscle strength and muscle size

What Are the Benefits of Blood Flow Restriction Training?

BFR training claims to be able to develop both strength and hypertrophy more effectively than strength training alone. But is it true? Fortunately, there are studies to indicate that this kind of training can be effective and that the claims are real. Many studies are small, but they all point to benefits of BFR (1).

Build Strength with Less Weight and Less Time

The main reason that people turn to BFR training is that it provides a great workout with smaller weights, fewer reps, and less time. Results of BFR done right should include increased strength, increased hypertrophy, and improved muscular endurance. 

While you can get these same results with more traditional strength training and lifting, what makes BFR so appealing is that it allows you to get the results in less time. Because the bands enhance the oxygen deprivation in the muscles being worked, you can use smaller weights and fewer reps to get the same results. 

Your clients want results, period. But they also will be happy to get those results with less effort and in a shorter amount of time. These are great reasons to incorporate BFR training into regular exercise sessions. 

Blood Flow Restriction Training May Help with Rehab from Injuries 

BFR training is used in physical therapy because it allows patients to develop strength with less load. Using smaller weights puts less strain on limbs and joints, which benefits the injured patient. They can grow muscle mass and strength more safely. 

Resistance bands are great tools for helping clients correct form and do resistance training safely. This blog will help you figure out how to incorporate bands into a training plan to prevent and correct injuries and pain. 

Increased Strength for Clients with Limitations

Injuries are not the only limitations that prevent some people from doing full-out strength training. Studies have shown that people with chronic pain, who are recovering from surgery, or who have certain health conditions that reduce muscle mass can benefit from BFR training (2).

Many of these kinds of clients simply cannot do the type of strength training that, alone, would lead to improved muscle mass and strength. They may be able to use lighter weights but only get minimal results. BFR training offers improves results when combined with less intense strength training. 

Of course, if you have clients with specific health conditions, it is important that you work with a medical professional to plan their training. This type of client must get doctor or physical therapist approval before beginning any kind of new exercise. 

Risks of BFR Training

Yes, there are benefits, but occlusion training can also be risky. Using the wrong type of equipment, using too much pressure, or working with someone who doesn’t know how to do BFR correctly can lead to complications and damage. And, there are certain health conditions that contraindicate restricting blood flow at all. 

Potential Complications

Even with healthy, fit clients, restricting blood flow improperly can cause harm. Too much pressure on blood vessels, for instance, can trigger blood clots. Not properly treated, a blood clot can lead to a pulmonary embolism or even a stroke. These can be fatal. 

The pressure of a BFR cuff may also potentially damage nerves and muscles. Muscle damage usually occurs with the eccentric phase. Some signs of damage caused by BFR include muscle weakness, limited range of motion, soreness, and swelling. 

Although not common, it is possible to acquire severe muscle damage from improper BFR training. This includes rhabdomyolysis, the breakdown of skeletal muscle (1). Rhabdomyolysis results in the release and build up of myosin, a protein, in the blood. Ultimately this can cause kidney damage. Symptoms include decreased urine volume and dark urine, weakness, muscle stiffness and soreness, joint pain, and fatigue. 

Don’t Use BFR with These Health Conditions

Most healthy clients can use BFR training safely and get the benefits if they have the right guidance. However, there are certain medical conditions that when combined with BFR can cause serious issues. For instance, someone with a history of blood clots risk even fatal complications when restricting blood flow. 

Other medical conditions to be aware of include high blood pressure, heart disease, any type of vascular disease, and poor blood flow or circulation. Anyone with these conditions should refrain from using BFR because of the risk of stroke. Never let your pregnant clients use this training technique either. 

Should You Use BFR with Clients? 

Before using BFR with any clients, make sure you understand how it works and how to do it safely. Work with another trainer experienced in using the technique or with a physical therapist. Safety should be the primary consideration.

For most healthy clients, BFR can be a beneficial addition to training. But, if you have any doubts about whether someone should be using the training technique, have them talk to their doctor about it first. 

Studies have found that there are some basic guidelines for using blood flow restriction training safely and effectively during strength training (1):

  • Aim for two to three sessions per week. For patients rehabbing an injury, BFR can be done once or twice a day but only for up to three weeks. 
  • Use a load that is between 20 and 40 percent of the client’s 1RM (one repetition maximum load). 
  • Do two to four sets, for a total of five to ten minutes for each exercise. 
  • Rest 30 to 60 seconds between sets. 
  • Each rep should last one to two seconds, including the concentric and eccentric movements. 

It’s not a bad idea to take a specific training class in BFR before beginning to use it with clients. This kind of training can be a powerful tool to help clients meet goals, but it does come with some risks so use care. 

You can be a better coach by offering more training specialties like BFR. Try earning a new certification through ISSA in Exercise Therapy to learn new strategies for helping clients prevent and recover from injuries.



  1. Patterson, S.D., Hughes, L., Warmington, S., Burr, J., Scott, B.R., Owens, J., Abe, T., Nielsen, J.L., Libardi, C.A., Laurentino, G., Neto, G.R., Brandner, C., Martin-Hernandez, J., and Loenneke, J. (2019). Blood Flow Restriction Exercise: Considerations of Methodology, Application, and Safety. Front. Physiol. 10: 533, doi: 10.3389/fphys.2019.00533 Retrieved from
  2. Hughes, L., Paton, B., Rosenblatt, B., Gissane, C., and Patterson, S.D. (2017). Blood Flow Restriction Training in Clinical Musculoskeletal Rehabilitation: A Systematic Review and Meta-Analysis. British Journal of Sports Medicine. 51, 1003-11. Retrieved from