Some recent studies using blood flow restriction training.

http://journals.lww.com/acsm-msse/Fulltext/2011/05001/Rapid_Increases_in_Myogenic_Satellite_Cells.2154.aspx

http://journals.lww.com/acsm-msse/Fulltext/2011/05001/KAATSU_Training_Improves_Strength_and_mCSA_of_the.130.aspx

I am at the club industry conference right now.  I attended one of the presentations by Wayne l westcott. He talked about how when we do drop sets we are getting the type 1 fibers to maintain tut. We usually say we are trying to get the type 2 fibers with a drop set.

It is suggested in research using blood flow restriction, type 2a fibers are more rapidly recruited and may be why greater hypertrophy is seen using the technique.

Sounds like a interesting conference. Look forward to more of your observations.

Rest period between each set of strength training seems mandatory. For example, after doing a set of 8 rep max training, before attempting the next set of same technique or any other technique for this muscle’s antagonist, the rest required may be up to 3 minutes. During this mandatory rest period, how one can perform the next set with a lesser load (drop set?) for the same muscle? Is there a chance for ‘Diminished proprioception after that set and risks of joint damage by attempting drop set’?

Usually with blood flow restriction training, the load 20-30% of 1RM, allows more rapid recovery. I have been attempting the use of wraps to see the effects personally. Most of the studies use around 30 sec. rests between sets keeping the limb under constant tension. Four sets are commonly utilized with a higher volume(around 30 reps) first executed and then three trailing sets of around 15 reps. This is not a conventional routine. The purpose is to buildup as much fluid dynamics by blocking blood flow and the change that occurs from this action appears to stimulate mTor, suppresses myostatin, may increase growth hormone and activate type 2a fibers more efficiently.

I came to know about this blood flow restricted training only after reading the articles of your forum.

With curiosity, I just wanted to ask, ‘if the circumferential pressure around the limb itself acts as a resistance to that muscle and that ” resistance caused by circumferential pressure around the limb + 20-30% 1 RM” actually equals a higher percentage of 1 RM, so you are getting the hypertrophy of muscle? My doubt is, it may not be the restriction of blood flow alone that causes hypertrophy.

The reason why this form of training seems to work is still under investigation and several theories exist. There may well be some physiological effect that we do not understand and is difficult to quantify. One theory is that the restricted flow sets up early activation of type 2a fibers. Personally, early attempts at testing with wraps does produce reduction in the rep max with the lower load. This combined with short rest intervals may compound the effect.

Whether the load itself is significant, using a 20-30% of 1RM, the studies that I read in which the same load without restriction was used showed little benefit. Interesting, one study if I can find it again, showed little benefit with high loads. So the time under muscular tension when pressure/wrap is utilized appears to be significant factor.

Thanks for sharing. I keep asking myself from a view point other than hemodynamic principle and share my question here.

If an individual is able to perform 10 reps with 30 kg, then his 1 rep max can be 40 kg. With certain amount of cuff pressure, say 100 mm Hg, if he is able to perform only 6 reps, then his 1 rep max with 100 mm Hg can be 36 kg. Based on this example, can we hypothesize that;

a. 100 mm Hg = 4 kg
b. Performing 10 reps using 30 kg = Performing 6 reps using 30 kg with 100 mm Hg
c. Performing 1 rep using 40 kg = Performing 1 rep using 36 kg with 100 mm Hg

I recently noted in an article that this occlusion training was used by men during space travels (perhaps because they couldn’t carry much exercise tools?). Really amazing idea!