Do The Hard Stuff

by Charles Poliquin
The most common training mistake is choosing the easy way out: choosing the exercises that don't recruit the most muscle. Leg extensions vs. squats, back extension vs. deadlifts, etc.
Basically, hypertrophy is a function of load time under tension within a certain limit. It's always a matter of how many motor units you can recruit. Bench pressing with chains is going to do 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 divide them into two groups. One group does squats with chains, deadlifts with bands, bench press with chains, and chin-ups. The other group does the leg extension, leg curl, machine bench press, and lat pulldown. The difference in hypertrophy would be monstrous between the free-weight accommodating resistance group verses the machine group.
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. And when in real life would you have to overcome resistance in a seated position? Never.
One more 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.
Now, machines can sometimes be a good source of variation for the "beach body" lifter. In bodybuilding, the muscles don't have to have any other function. They just have to look pretty. It doesn't matter if you use rocks or selectorized weight machines, as long as you have enough load and you last long enough (time under tension), you can hypertrophy.
I'm not dogmatic enough to say that machines are "evil." It depends on the population. The executive doesn't care how heavy he can go on the incline dumbbell press; he just wants to look good in a bathing suit at the five-star resort. Whether he used machines or dumbbells doesn't really matter.


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