|
2002/11/22, 01:20 PM
From Men's Health's Lou Schuler:
Q: A guy in my gym recommended that I "pre-exhaust" my muscles by performing a superset in which I do an isolation exercise followed by a compound exercise. For instance, a triceps pushdown immediately followed by a close-grip bench press to completely fatigue and build my triceps. It definitely makes my arms tired, but I can't lift very much weight on the second exercise, so I don't feel like it's doing much good. What's your take?
A: Bodybuilders tend to be obsessed with muscular fatigue. But the problem is that an exhausted muscle can't generate maximum force, since the glycogen has been depleted. And without maximum force, you can't tap into all the muscle's fibers.
A lot of workout systems -- SuperSlow is the biggest offender, but most bodybuilding programs are guilty of this, too -- work on the theory that the more tired your muscles are, the more muscle fibers you'll call into play.
The truth is the opposite. When your muscles are fresh, they're capable of using the most muscle fibers. The perfect workout (albeit for a lifter with 2+ years of experience) is probably sets of 3 reps with the heaviest possible weights, and full recovery (3 to 4 minutes) between sets.
Your body uses muscle fibers on what's called the size principle. When given a challenge, it starts out using the smallest, lowest-threshold fibers, and then works its way up to the biggest, highest-power fibers.
Those high-threshold fibers, coincidentally, have the greatest growth potential.
This process happens faster than you can think about it, so you don't notice that your puny little Type I, endurance-oriented fibers are the first ones recruited for that maximum deadlift.
But the point is important: When you're lifting a maximum weight, all the fibers, from smallest to largest, are called into action. When you lift a lighter weight, your body stops when it has enough fibers called into action to lift the weight. So no matter how taxed your smaller fibers are, your biggest fibers won't get involved in lifting a sub-maximal weight. Your smaller fibers just keep recycling themselves, dropping out from exhaustion, then getting back into the set when they've recovered.
Pre-exhaust, SuperSlow, drop sets, and other techniques may really be better for exhausting and growing the smaller muscle fibers.
But those fibers have less total growth potential then the biggest Type II fibers, which only go to work on the heaviest weights (or to move lighter weights as fast as possible, as in ballistic, Olympic-type lifts).
Working smaller fibers to exhaustion is a good strategy for guys on steroids -- it clearly works for them. (I confess I don't know why.) For guys not on steroids, you won't get maximum muscle growth until you tap into the biggest fibers and make them grow. The smaller ones will grow along with the big ones, thanks to the size principle.
--Lou Schuler, C.S.C.S.
----------------------------
"Don't follow leaders and watch your parking meters!"
-- Bob Dylan
|
