What the heck is Kaatsu? If you’re thinking about the breaded and fried Japanese chicken dish, that’s “katsu,” and it’s not even close. But if you were thinking about or have ever heard of “blood-flow restriction training,” also called “occlusion” training or blood-flow moderation training, then you’re on the right track. The word “Kaatsu” itself pretty much describes the practice as the word “Ka” means “additional” and “atsu” is synonymous with “pressure,” thus “training with applied pressure.”

While there is no shortcut to good health and a fit, toned body, there may indeed be a shortcut when it comes to putting on muscle mass. Hard to believe? Yes. But, with a few well-researched and curious tweaks to your workout regimen, you very well may find yourself adding size more easily than you thought.

A Brief History of Kaatsu

So, now that you know what we’re talking about (exercise, not chicken), you may be wondering where this seemingly odd method of working out came from and how it came about.

It all began back around 1966 in Japan when a young Dr. Yoshiaki Sato was sitting in Seiza, a traditional Japanese way of sitting which entails bending your knees so your lower legs are directly beneath your thighs and your hips rest directly on your heels. While in this position, he lost circulation in his calves and began to massage them to relieve the pain. This got him thinking about how moderating blood flow could have other long-range benefits if used properly and with certain results in mind.

Fast forward to 1994 when Dr. Sato applied for patents for his Kaatsu Training Bands, designed to help people modify blood flow to injured areas to promote greater and faster healing. Thus began the popularity of the BFR (blood-flow restriction) band training workouts.

What is Blood-Flow Restriction Training?

Blood-flow restriction to muscles during training has been around for decades but has recently resurfaced as a popular way of training for muscle growth (hypertrophy). This type of training is known by various other names such as Kaatsu, occlusion training, BFR, etc.

Essentially, you use a wrap, cuff, or band tightened just enough to cut off the blood flow from your veins, but not so tight that it restricts your arterial blood flow. And it’s very important to get the pressure correct and not too tight, so you avoid damage.

Why is this helpful? Well, according to the theory, when you perform resistance training with heavy weights, you build up a byproduct of that exercise in your muscles called lactic acid. Lactic acid is important when it comes to building muscle, and if you can’t lift heavy weights, then you may feel your muscle-building efforts are just not paying off. Enter Kaatsu training, which may allow results even with less weight lifted.

When lifting with the Kaatsu method, a high volume of exercise is performed but with a significantly lighter weight than usual. This has been shown to cause an intense pump within the muscle, buildup of lactic acid, release of growth hormone, and an overall increased intensity to the workout.

According to scientists, where an individual would normally need approximately a 70% load of their one-repetition max to build muscle, with BFR training, they can use as little as 10% – 20% of their normal lifting weight and still cause muscles to grow.

Less blood flow also means less oxygen to the area. And, when exercise is continued while oxygen levels are low, muscles are forced to tap into the type 2 fast-twitch muscle fibers, which may help pack on more muscle mass.

What are the Health Benefits of Kaatsu?

Kaatsu, or blow-flow-restriction training, purposely limits the outflow and inflow of blood to the targeted area. This enables the muscles to benefit in many ways, including some of the following:

• Once the bands are released, the extra blood and oxygen that rush to the muscle may aid in both healing and growth.
• May increase muscle growth of type 2 fast-twitch muscle fibers.
• May stimulate increased protein synthesis for faster generation of muscle mass.
• Gentle—because less weight is lifted yet many experience the same or better results in muscle growth. This may mean safer, easier, and more gentle workouts for people with injuries, recovering from surgery, or those with joint issues.
• Anti-aging—it has been suggested that occlusion training may also help delay aging and improve metabolism when practiced regularly.
• Greater hormone release—this type of training appears to garner the release of growth hormone to help build muscle mass.
• Faster recovery—because lighter weights are used and blood flow to the areas worked increases, there is the potential for faster than normal recovery times.

How to Perform a Workout with the Kaatsu Method

Remember, the main premise behind occlusion training is to be able to increase the size of your muscle while at the same time lifting lighter weights. This type of training is not ideal for every person, every body part, or every kind of workout. It’s important to work with a professional to determine if this type of work out is safe for you.

Once that’s been determined, the best results typically come from placing the wrap between your shoulder and biceps muscles on each arm or on your upper thighs right below your hips.

How tight should you make your wraps? Well, you definitely don’t want to completely cut off circulation, which could cause serious harm. At the same time, you want to limit blood flow into and out of the muscle. The general recommendation is to tighten the wrap to about a perceived “Level 7” out of 10.

Once you have your bands in place, the rest is pretty straightforward. Just perform your workout as you normally would only with a very light weight. Perform higher reps per set (in the range of 20 – 30 repetitions per set).

Again, there may be risks, especially if the pressure is too tight, and many of the study authors recommended additional research before applying the technique widely. So, if you’re interested, ensure you understand the risks and work with a professional. But this new type of training does show exciting and promising applications.