
When most people think of strength training, they often envision heavy weights and intense, prolonged workouts. However, there’s a lesser-known technique that we’ve been teaching in our certification courses for almost 15 years that challenges this notion: blood flow restriction (BFR) exercise.
BFR is a fascinating approach with thousands of research studies available in support of this extremely effective and time-efficient methodology. Because we use BFR constantly we wanted to share some more information about it with you this week.
BFR: The Origin Story
In the 1960s, Dr. Yoshiaki Sato, a Japanese sports scientist, began developing the concept of “blood flow moderation” or “Kaatsu training.” Inspired by traditional martial arts training methods that involved tying ropes around limbs to induce muscle fatigue, Dr. Sato wanted to identify a replicable approach to recreate the physiological responses observed in these practices for training and rehabilitation. His goal was to create a safe and effective method to achieve muscle hypertrophy and strength gains using lighter loads without generating excessive fatigue that would interfere with other sports training.
Over the following decades, Kaatsu training gained traction and made significant advancements. In the 1990s, the first commercially available BFR devices were introduced, facilitating standardized cuff pressure and greater control of many training variables. Researchers, including Dr. Jeremy Loenneke, Dr. Takashi Abe, and Dr. Johnny Owens, conducted studies to explore the physiological mechanisms and potential benefits of BFR exercise.

A Brief Look at the Science Behind BFR:
As you probably gathered from reading the history, BFR exercise involves applying a specialized cuff or tourniquet to the upper arms or thighs, limiting blood flow to the working muscles during exercise. This restriction creates a controlled environment where metabolic stress and muscle fiber recruitment are potentially maximized, leading to significant adaptations and improvements that mimic, or even surpass, more traditional strength training approaches.
Contrary to traditional beliefs that focus on strength training loads above 70% of a 1 repetition maximum (1RM) to generate muscular adaptation, BFR exercise has been shown to elicit substantial muscle growth and strength gains even with low-intensity (20-40% of 1RM) resistance training. The metabolic stress induced by BFR exercise triggers the release of growth factors like insulin-like growth factor-1 (IGF-1) and contributes to muscle hypertrophy. The recruitment of fast-twitch muscle fibers, typically associated with heavy lifting, is also enhanced during BFR exercise, leading to increased strength gains.
Additionally, BFR exercise also promotes remarkable vascular adaptations. The restricted blood flow creates a hypoxic environment that stimulates the release of vasodilators and growth factors like vascular endothelial growth factor (VEGF). These responses lead to angiogenesis, the formation of new blood vessels, which enhances nutrient and oxygen delivery to the working muscles. Improved vascularity not only supports muscle growth but also enhances overall athletic performance.
With this background out of the way, let’s dig into applications:
BFR General Applications
- Muscle Hypertrophy and Strength Gains: The metabolic stress and muscle fiber recruitment triggered by BFR exercise create an environment conducive to muscle growth and adaptation. BFR exercise has shown efficacy in enhancing hypertrophy and strength in both young and older individuals.
- Metabolic and Cardiovascular Adaptations: BFR exercise leads to unique metabolic and cardiovascular responses. The restricted blood flow and subsequent release of the cuff result in rapid blood flow restoration and a significant increase in metabolite accumulation. This metabolic stress stimulates the release of growth factors, such as insulin-like growth factor-1 (IGF-1) and vascular endothelial growth factor (VEGF), which contribute to muscle hypertrophy and angiogenesis.
- Rehabilitation and Musculoskeletal Conditions: BFR exercise has shown promise in rehabilitation settings for various musculoskeletal conditions. It can facilitate muscle activation, improve muscle strength and function, and accelerate the recovery process following injuries or surgeries. BFR exercise has been studied in populations with knee osteoarthritis, tendinopathies, and post-operative rehabilitation, showing positive outcomes and aiding in functional recovery.
BFR and the Nervous System
- Enhanced Blood Flow and Oxygenation: During BFR exercise, the restricted blood flow and subsequent release of the cuff result in a rapid surge of blood flow to the working muscles. This heightened blood flow and oxygenation also extend to the brain. Increased blood flow to the brain enhances oxygen and nutrient delivery, providing the fuel necessary for optimal brain function.
- Neuroplasticity and Cognitive Benefits: One of the remarkable effects of exercise, including BFR exercise, is its ability to promote neuroplasticity—the brain’s capacity to reorganize and form new neural connections. Through the release of growth factors like brain-derived neurotrophic factor (BDNF), BFR exercise supports the growth and development of neurons, enhancing learning, memory, and cognitive function.
- Neurogenesis and Brain Cell Development: Exercise, including BFR exercise, has been shown to stimulate neurogenesis—the creation of new brain cells in areas critical for learning and memory, such as the hippocampus. This process plays a vital role in maintaining brain health and combating age-related cognitive decline.
- Neurotransmitter Regulation: BFR exercise affects neurotransmitters, the chemical messengers that facilitate communication between brain cells. Regular exercise has been found to modulate neurotransmitter levels, including dopamine, serotonin, and endorphins, which play key roles in mood regulation, stress reduction, and overall mental well-being.
- Cognitive Performance and Mental Resilience: Engaging in BFR exercise can enhance cognitive performance and mental resilience. Research suggests that exercise positively influences attention, executive functions, and processing speed. Regular BFR exercise has also been associated with improved mood, reduced anxiety, and enhanced stress management, all of which contribute to better cognitive performance.
- Long-Term Brain Health: The cumulative effects of BFR exercise and regular exercise, in general, contribute to long-term brain health. Exercise has been linked to a decreased risk of age-related cognitive decline, neurodegenerative diseases, and improved overall cognitive function. BFR exercise provides an additional layer of potential benefit through its unique physiological responses.
After 30 years of work in the movement industry, BFR is revolutionizing the way we approach strength training. It is one of the only approaches we’ve ever seen consistently demonstrate excellent results in multiple studies. In short, BFR offers an efficient and effective solution for athletes, fitness enthusiasts, and individuals in rehabilitation while offering brain-based athletes and coaches a powerful tool to improve neural activity and function.
While the idea of using a cuff or tourniquet and lifting light weights may seem weird, we recommend that you embrace the tourniquet and unlock the potential to become stronger, fitter, and more resilient through the regular use of BFR.
On a practical note, we love combining BFR with the loaded mobility approach we teach in The Strength Gym for an incredibly fast and effective way to build strength, size, mobility, and motor control while also providing huge neural benefits.
Finally, while BFR is not a difficult methodology in application, it is important to consult with a professional before getting started to learn the proper technique for band placement, how to individualize band pressure for your body, appropriate exercise selection, and how to structure your training program.
We hope you enjoyed learning a bit more about BFR and are inspired to give it a try!