[quote]nyyanks25 wrote:
Don’t worry…i’m not starting a debate over whether compound and isolation lifts are better than one another.
my question is…
i’ve read a lot about certain iso exercises, like pec deck flyes and leg extensions to be harmful to the joints involved in those respective lifts(shouders, knees.) i’ve read that extreme torque and pressure is put on the knee during leg extensions. obviously these exercises are not performed with lower/heavier reps. i would always do them for a higher rep range.
is it a valid point that leg extensions are dangerous for the knees due to the “unnatural isolation movement” of this exercise?
thanks.[/quote]
I don’t use leg extensions much, but I remember profX talking about them in his thread… I believe he limits how far he’ll bend his legs/raises the angle or something like that? Don’t quote me on it, rather go and ask him or search for the “Professor X: a request” thread and read through it.
He’s been using leg extensions for a decade or longer without injury.
As for pec deck flyes… Ok, look.
Most people fuck their shoulders/bi-tendons up on the bench press because they bench with rounded shoulders/shoulders come off the bench while pressing, among other things.
If you do the same shit on peck deck flyes or flyes in general, you’ll likely get injured, too (or if you were to use too much of a range of motion).
Learn how to position your scapulae/shoulders for pretty much all pressing or extension exercise (even on curls and such, rounding the shoulders is not the best idea).
The only “isolation” exercise which I flat out think is pretty much always going to end up causing trouble are skullcrushers done the way most people do them (bar comes down on forehead or nose, upper arms perpendicular to the floor).
Just about everyone gets elbow tendonitis from them at some point, even the weaker guys it seems…
You can mess yourself up badly on just about every single exercise out there. Isolation or Compound, doesn’t matter.