Partial Reps?

[massive]

I recently watched arnies pumping iron dvd, and saw that when performing bench press or overhead press the rep range wasnt full.

The weight was brought all the way down then lifted only half to 3 quarters.

How muchy beneficial is this training method compard to the full rep range method?

 

[roccodart440]

The idea behind it is it keeps constant pressure on the muscle your working plus it aids in eliinating the support group.

I don't train this way but those guys were unreal so maybe it works?