Fat-Burning Diet and Nutrition Guide

That’s about an 800 percent increase in gains when blood flow
was impeded. (You read those numbers right. Unbelievable!)
Why does blocking blood flow produce such spectacular
increases in muscle size and strength? Part of it may be due to
the incredible rush of blood to the bodypart once blood flow
resumes. Scientists have suggested that the bloodbath that
occurs can produce everything from upgraded release of heat
shock proteins to alterations in muscle calcium metabolism to
greater recruitment of fast-twitch muscle fibers.
That last one makes a lot of sense—greater recruitment of
fast-twitch fiber s—a direct re sult of ra mpin g up m uscle
energetics with extra blood. Let us explain: If you block blood
flow to a muscle for a minute or two, the moment you remove
the occlusion, it’s like a damn breaking—blood floods to the
choking bodypart like a tidal wave. Now if we relate that to the
size principle of fiber re c ruitment—the low threshold motor
units fire first (slow-twitch endurance fibers), followed by the
mediums followed by the high-threshold motor units—it could
be that with so much more blood (oxygen) in the muscle, the
slow-twitch endurance fibers carry more of the load early in the
set, sparing more fast-twitch re c ruitment for later. That would
result in more reps, i.e. impressive strength (20 percent would
take a 300-pound bench to 360 if you could occlude blood
from all the muscles involved for two minutes). Interesting stuff.
And it may explain why warming up a muscle is so important
for strength—it gets more blood in the muscle.
Okay, that may explain the strength jumps, but what about
the muscle size increases?
I t ’s possible that blocking blood flow works so well in
creating new size by affecting the slow-twitch, or type 1, fibers
as well. Those fibers are aerobic, which means they re q u i re
oxygen. One theory is that if you starve them of oxygen with
occlusion early in the set, they adapt by getting larg e r — a n d
that means you get bigger faster!
Bodybuilders tend to focus on the fast-twitch fibers because
they’ve had it hammered into their heads that those are the