KAATSU: Vascular Occlusion Training

What is vascular occlusion training?

In the world of fitness, it is rare that new training techniques are developed. Most of the time, it is simply old techniques inlaid differently to bring them up to date. We rarely reinvent the wheel. The principle of KAATSU was developed by the Japanese scientist Y. Sato in 1966: it is a training technique aimed at increasing muscle mass without having to use heavy loads. Sato first developed the idea during a Buddhist ceremony where, having had to stay on his knees for a long time, he made the connection between the blood occlusion in his calves and the burn perceived during training. Many years of experimentation were necessary before this process reached us in the West, in the 90s. However, it has been used since the 80s in Japan, when the necessary equipment for KAATSU became available.

What is KAATSU?

The principle is simple: Work on strength and hypertrophy using lighter loads than usual by achieving vascular occlusion in a limb. It is simply a matter of placing an elastic band around the limb to be trained (arm or leg), the compression having the effect of preventing venous return. The arteries then pump blood to your muscles, but the superficial occlusion created by the elastic band prevents your veins from draining blood. The result: an accumulation of oxygen-deprived blood (congestion) and loaded with metabolic wastes like lactic acid, hence the burning sensation.

If you do not want to go into the details of training with vascular occlusion and you only want to know how to implement it, you can go directly to the section “How to implement it in your training?” below.

What are the mechanisms of KAATSU?

Here are the reasons why Vascular Occlusion (OV) works for strength and hypertrophy:

• Metabolic stress : Identified as one of the three main factors of muscle hypertrophy , along with muscle tension and muscle damage (microlesions). Metabolic stress causes a hypertrophic response. This is why keeping the bands between sets works better than taking them off each time. The KAATSU therefore makes it possible to create an equivalent metabolic stress but with much lower loads. As a guide, training with OV is equivalent, in terms of metabolic stress, to training with 65% of your 1RM * without OV.
• Motor unit recruitment: Research shows that motor unit recruitment is significantly higher when training with OV with light loads (especially with constant OV) than training with light loads without OV. In addition, the recruitment of motor units is similar between training with OV and low loads and conventional training without OV. This, as we will see later, is probably the biggest benefit of training with OV. ( Research 1 Research 2 Research 3 )
• Cellular swelling: Similar to metabolic stress, the swelling of cells has been identified as a mechanism that can cause hypertrophy. Muscle thickness increases by approximately 11.5-12% directly after training with OV, due to the increase in fluid in the muscle, which implies cellular swelling .
• Modification of hypertrophy signaling pathways and gene expression. Key signaling pathways ( like the mTOR pathway ) and genes (like the Myostatin gene ) are more affected by training with OV and low loads than training at low loads without OV. Training with OV, just like regular training with heavy loads, affects them in a similar way, increasing protein synthesis and decreasing myostatin . ( Article in French )
• Proliferation of satellite cells and myonuclear addition : the incorporation of new myonuclei is an essential factor for long-term hypertrophy. Muscles can grow until muscle fibers reach their myonuclear domain limit without adding myonuclei, but in order to continue to grow, adding new myonuclei from satellite cells is crucial. A drive low load with OV, as a classical training with heavy loads, increases the reserve of satellite cells and causes the addition myonucléaire much more efficiently than training at low load without OV.
• Growth hormone secretion : It is difficult to say, at this point, whether elevations in these conspicuously anabolic hormones significantly affect muscle growth. However, low load training with OV to failure results in growth hormone levels 290 times higher than at rest, and about 4 times higher than low load training without OV.

What is its role in muscle hypertrophy?

Overall, low intensity OV training appears to be as beneficial for hypertrophy and strength as conventional heavy weight training.

So we have similar effects between low intensity OV training and conventional training. It is hardly surprising to get similar hypertrophy with this type of training because we know that the determining factor for hypertrophy is the overall volume which translates into the number of sets of work for a given muscle group. In contrast, the fact that the effects on strength are similar is puzzling, as intensity is usually the determining factor for strength gain. OV with light loads leads to muscle activation almost identical to that of high intensity training.

This meta-analysis is based on training only with OV and not on classic training with incorporation of OV as an accessory. This is why the following 5 searches are interesting, because apart from injury, I doubt you want to base 100% of your training on OV.

Here are the 5 additional studies allowing us to bring new conclusions:

1. https://www.researchgate.net/ publication / 258280252_ Practical_blood_flow_ restriction_training_ increases_muscle_hypertrophy_ during_a_periodized_ resistance_training_programme
2. https://www.ncbi.nlm.nih.gov/ pubmed / 24476782
3. https://www.ncbi.nlm.nih.gov/ pubmed / 22105051
4. https://www.researchgate.net/ publication / 236580429_Three_ Weeks_of_Occlusion_Training_ Can_Improve_Strength_and_ Power_in_Trained_Athletes
5. http://scholarcommons.usf.edu/ cgi / viewcontent.cgi? article = 6283 & context = etd

Here is what we can learn from this research which combines high intensity training as well as low intensity OV training on already experienced athletes:

• Low-load OV training works just as well as heavy muscle-building training (Lowery study), although the effects of the combination of the two may not magnify the hypertrophy. The Leubbers study showed that adding OV training to high intensity training did not increase hypertrophy, but the Yamanaka study did.
• It appears that training with OV does not only affect muscles with occluded venous blood flow. The Yamanaka study (increased breast growth when the bands were applied to the arms) and the Cook study (improved bench press performance when the bands were applied to the legs) demonstrated an increase in weight loss. strength or hypertrophy in muscles that were not directly affected by the OV.
• The most noticeable effect seems to be an increase in strength. Leubbers' study showed strength gain in squat, Yamanaka study showed strength gain in squat and bench development, as did Cook's study. O'halloran's thesis showed that by replacing part of the high intensity training with training with OV and low loads, there was the possibility of generating the same strength gains!

The congestion that accompanies training with OV might lead us to believe that the biggest difference is in the hypertrophy. However, research shows mainly effects at the level of strength. Thinking about it rationally, it makes sense. Muscles increase for several reasons: tension, training volume, accumulation of metabolites, muscle damage, etc. With a training under OV, there is less mechanical tension, there is a strong accumulation of metabolites, however not higher than that generated by a classic training (~ 10reps) but there is very little muscle damage (there are exceptions). This type of training therefore generates a strong growth stimuli similar to a classic training, and even in addition,

Regarding strength, we know that it is dependent on structural and neuronal factors (your muscle mass and how you are able to activate it). We also know that training with OV and low loads causes muscle activation similar to conventional high intensity training. In terms of hypertrophy there may be significant advantages in addition to conventional training, apart from the study by Yamanaka. But for strength athletes, it is an extraordinary tool:

• When you add it to your heavy training, it makes you stronger than heavy training alone. And it's not just a matter of extra workload since it makes you stronger than extra work without OV.
• The recovery time is quick because there is hardly any muscle damage. You may feel sore the first time, but this is usually due to the novelty of the exercise.
• Because it also causes strong muscle activation, it also helps at the neuronal level of strength development. The effects are similar to high intensity training. O'halloran has even shown that you can replace some of your heavy training volume with low loads with OV and get the same strength gains!

So it's easy to add it to your current workout without compromising your recovery. Another way, if you are having trouble recovering, you can substitute it for sets of work without compromising your strength gain.

However your training should not only revolve around the OV because this type of training does not stress your tendons in the same way as heavy loads , probably because of the induced mechanical tensions.

Vascular occlusion as part of prevention or after injury

Originally the KAATSU was developed for efficient training with low loads, which makes it very popular with the elderly as well as in rehabilitation after injury.

In fact, training with OV greatly limits stress on tendons and joints , which allows muscular solicitation without imposing significant mechanical tensions on a muscle in the process of healing, for example.

Training with OV helps reduce muscle wasting during injury and accelerates strength recovery when resuming training. Research shows faster recovery, in terms of muscle mass and strength, with rehabilitation with OV.

For people who can not have physical activity due to injury or other, OV can limit muscle loss. This technique therefore allows you to train around your pain and limitations. To find out more, I recommend this summary .

I mainly use it in prevention for tendonitis and other pain due to training in the knees, elbows, wrists and ankles. This makes it possible to reduce the volume of heavy work on the triceps for example, which are already used on all the press exercises (bench press, shoulder press, etc.)

Here is how to implement it in your training.

How to implement it in your training?

1. The material:

• Any elastic knee band will do, you can even use some strength training elastic bands .
• For a slightly more precise material you can use the following specific bands: BFR Bands
• If you are very serious with training with OV or you are a health professional (rehabilitation), there are the following systems: Expert / Professional

Avoid rigid and / or too thin bands, you could injure the underlying nerves.

2. Setting up

Apply the bands with a perceived pressure of 7 for the legs and 6 for the arms, on a scale where 0 is no pressure, and 10 is the pressure of a tourniquet before an amputation. The pressure on the legs may be greater because there is more fatty tissue and they deform less under pressure.

You can measure the tension of the tape with the length you stretch it: take point A and point B or you hold the tape and measure the length in between. The difference in stretch length indicates how much pressure you are applying to the limb in question.

If you experience pain, limb sleep, tingling, or marked skin discoloration before you even start the exercise, the band is too tight.

As indicated above, I do not recommend removing the bands between sets, first for convenience, then because research shows poorer results.

3. Weights, repetitions, sets:

Use a low load, about 30% of your 1RM (you should be able to do about 30 reps when cool).

Do as much repetition as possible on your first set, rest for 30 seconds, and start your new set.

3-4 sets with a total of 60-100 repetitions is most common in research associated with OV training.

Note that the lower the intensity (if you want to use less than 30%) the shorter the rest time.

4. What are the dangers?

Compared to high intensity training with heavy loads, training with OV is much safer. It should be remembered that it was developed for the elderly or recovering from injury.

Theoretically, blood flow to a limb can be completely cut off for 1 hour without long-term risks. In the case of vascular occlusion, the arterial arrival is always active.

In order to be careful, limit the series to the number of 4.

Summary: Information to remember

1. Vascular occlusion (OV) training involves cutting off the venous blood flow of a limb, without interrupting the arterial flow, which will cause unusual congestion.
   
2. Contrary to what one might think, a training with OV has no advantage in terms of hypertrophy compared to a classic training.
3. One of the biggest benefits of OV is the strength gain when paired with high intensity training. It causes strong muscle recruitment, similar to heavy loads, causing very little muscle damage. It therefore allows you to become stronger without compromising recovery, it is an additional volume of training without constraint.
4. Overall, it improves recovery after training and reduces muscle wasting during injury. It also allows hypertrophic work with low loads which can be beneficial in many situations.

Who is training with vascular occlusion for:

• Beginners benefit from the high metabolic stress generated by the OV to obtain a complete recruitment of muscle fibers without muscle damage, which allows them to considerably increase their training frequency.
• Endurance athletes in particular benefit from the synergy between strength training and metabolic stress.
• Elderly and / or injured people benefit from training that requires only a very low intensity of work (light weight).
• Strength Athletes / Powerlifters: Additional strength gain without adding training volume and without compromising recovery.

* 1RM: The 1RM or “maximum on one repetition” corresponds to the load that can only be carried, pulled or lifted once.

Related research and references:

1. Bayesian Bodybuilding PT Course / bayesianbodybuilding.com
   

2. Stronger By Science / strongerbyscience.com