What is blood flow restriction training? At its core, this training method is exactly what it sounds like: Restricting blood flow to muscles during training. This is usually done using specialized equipment such as a blood flow restriction (BFR) cuff. .
It’s the reported benefits that get people’s attention that BFR claims can stimulate impressive muscle growth and strength gains from resistance training at lower loads.
It has also been suggested that BFR can be used during low-intensity aerobic exercise, such as sessions on the best walking treadmill. (opens in new tab) – To prevent atrophy and muscle loss in people who are unwell, such as the elderly or injured.
To help you separate fact from fiction, we spoke with Jeremy Roeneke, an associate professor of exercise science at the University of Mississippi and an authority on blood-restriction training.
Jeremy Loenneke is director of the Kevser Ermin Applied Physiology Laboratory at the University of Mississippi, and the main focus of his research group is the adaptation of skeletal muscle to exercise with or without the application of blood flow restriction. He is a Fellow of the American College of Sports Medicine and a member of the American Physiological Society.
What is blood flow restriction training?
As outlined above, BFR involves restricting blood flow to currently working muscles. Loenneke provides this summary. “In blood flow restriction training, a cuff or wrap is applied to the working limb (such as the top of the leg or the top of the arm) to partially restrict blood flow to that limb.
“This restriction is combined with low-intensity resistance exercise or low-intensity aerobic exercise. (opens in new tab) Because it produces effects similar to high-intensity or high-intensity exercise. ”
As an example, you can use BFR when doing bicep curls. When performing this exercise, place and tighten a cuff around the proximal part of your arm (the part closest to your body) to restrict blood flow to the working muscle (biceps). This allows him to lift lighter weights while experiencing the same muscle hypertrophy, says Loenneke. (opens in new tab) Intensity benefits of training with heavier loads.
How blood flow restriction training works
Loenneke says it’s not entirely clear how blood flow restriction increases muscle size, but it’s likely similar to traditional resistance exercise.
“In other words, when a muscle contracts, that contraction initiates a signal that turns on growth-promoting pathways (such as mTORC1) in activated muscle fibers. increase.
“Applying blood flow restriction causes the muscles to work harder than normal, leading to a higher level of muscle activation. This signals more fibers to grow, even when the load you lift is very light. means to send (20-30% of maximum intensity)”.
What equipment do you need?
A cuff or wrap is required to perform blood flow restriction training.And due to the popularity of practice mountings, many of these products are commercially available in stores and online.These cuffs are available in two main styles, he said: Inflatable like the B Strong Cuff. (opens in new tab) Practical below.
“There are many commercial options available for those interested in applying blood flow restriction,” says Loenneke. “The main components include the cuff and a device for inflating the cuff.
“Many of the commercial devices available today also allow for personalized extremity pressure settings, that is, pressures that take into account the cuff used and the size of the extremity to which it is applied (e.g., cuff applied to 40%).The pressure required to completely block blood flow).
“Another method is to apply a practical blood flow restriction via an elastic wrap or cuff. This method is called ‘practical’ because elastic wraps are easy to find and inexpensive.” will be The drawback of this method is that there is no device to regulate the pressure, so it is impossible to know how much restriction is being applied. ”
what is the advantage
At first glance, the benefits of blood flow restriction may not seem real. That is, it promotes hypertrophy and strength gains while lifting lighter weights, thus reducing the risk of injury in exercisers and allowing unfit individuals to train more efficiently. There is literature to back it up.
“Most of the work [studying BFR] We focus on changes in muscle size and strength,” says Loenneke. “Blood flow restriction combined with low-intensity resistance training increases muscle size and strength.
“The change in muscle size is similar to high-load (70% of the maximum weight an individual can lift) exercise. However, in many cases the change in maximal strength is small and strength still increases. but not to the same extent.”
A 2010 study published in the journal Clinical Physiology and Functional Imaging asked 10 young men to complete 4 sets of a total of 75 bench presses at 30% of the maximum weight they could lift in one repetition. A task has been assigned. They did this twice a day, six days a week for two weeks. One group used elastic cuffs placed proximally on both arms for his BFR, while the remaining subjects performed the exercise without cuffs.
After 2 weeks, the BFR group had a 6% increase in maximum bench press, an 8% increase in triceps muscle thickness, and a 16% increase in pectoralis major (largest pectoral) muscle thickness. did.
In contrast, the maximum number of single bench presses in the control group decreased by 2%, and the thickness of the triceps and pectoralis major muscles remained almost unchanged (-1% and 2%, respectively).
This may be due in part to the ability of BFRs to influence the endocrine system. A 2016 study published in the European Journal of Applied Physiology (opens in new tab) Four weeks of low-intensity resistance training with blood flow restriction was found to significantly increase growth hormone levels.
The ability to obtain similar rewards from strength training and other forms of exercise may be beneficial for individuals or groups that use lower loads, resulting in less stress on the body and unable to participate in more strenuous activities. be.
“There are certain populations where slow walking or bicycling while restricting blood flow may improve muscle size and strength, but the biggest changes are in blood flow restriction and resistance type. Occurs when exercise is combined.
“Some studies suggest that the application of blood flow restriction alone may be able to slow the loss of muscle size and strength due to rest. However, the data for this are rather limited. I have.”
who should do
While it may not be mainstream among those who exercise regularly, blood flow restriction is something available to daily gym-goers looking to increase strength and muscle mass, Roneke says. . However, he recommends incorporating it into your workout routine rather than adding it to the end of an already full workout schedule.
“[Gym-goers] You can use it as part of your regular training program, or when you have an injury or want to add variety to your training,” says Loenneke. “Some people prefer to incorporate it at the end of their workout after doing some more traditional training.
“While this can be effective, it’s important to understand that muscles only respond to specific training sessions. adding another exercise that restricts blood flow hardly adds anything extra.
Is blood flow restriction training dangerous?
All exercise carries risks, but Loenneke says many concerns about BFR are unfounded. However, further research is needed.
“Two common concerns are muscle damage and the risk of blood clots. Based on the available literature, adding blood flow restriction to exercise does not appear to increase either risk. is assumed to be used properly.”
Existing literature supports this. His 2021 systematic review of research on the subject published in the International Journal of Sports Physical Therapy (opens in new tab), said: However, further studies are needed to fully determine the long-term systemic effects of BFR. ”
