The #1 Training Mistake
Q: Diet and lifestyle issues aside, what's the number one training mistake people make when their main goal is hypertrophy?
A: The most common mistake is choosing the easy way out: choosing the exercises that don't recruit the most muscle. Leg extension vs. squatting, back extension vs. deadlifting, etc.
Basically, hypertrophy is a function of load times TUT (time under tension) within a certain limit. It's always a matter of how many motor units you can recruit. So bench pressing with chains (accommodating resistance) is going to do far more for you than the same number of reps with a plate-loaded chest machine. You need to choose the exercises that give you the most bang for your buck.
Let's say you have ten sets of twins and you divide them into equal groups. One group does deadlifts with bands, squats with chains, bench with chains, and chin-ups. The other group does leg extension, leg curl, lat pulldown, and machine bench press. The difference in hypertrophy would be monstrous between the free-weight accommodating resistance group verses the machine group.
Another example: Take someone and have them do ten sets of six in the pull-up where each set is hard. Take his twin and have him perform ten sets of six in the pulldown. The difference in muscle mass gain is going to be night and day. You recruit more motor units with the pull-up.
The problem with plate-loaded machines is that the leverage is often too good. Every kid in high school can do five plates a side, but they can't do five plates a side with any barbell exercise. The only time they do five plates is when they go to IHOP. And when in real life would you have to overcome resistance in a seated position? Never.
Another problem with machines is the fixed pattern of movement. For that same reason, I think dumbbells are a better choice for most exercises than barbells, particularly if you're dealing with an athletic population.
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