T Nation

A Little Physiology

Does increases in Isometric strength at specific joint angles cause increase in strength at other joint angles? I was taught that it didn’t, but I seem to remember reading somewhere that it did. Any Ideas?

Yes it can. I believe the research shows a 15 degree carryover although it might be 30. In my opinion though it can be much greater than this if used properly.

I believe most research indicates a 15-25 degree carryover. This depends on the exercise and the joint angle being worked though.
Any carryover from partial movements to full range movements depends on where your weak points are. For example, if your bench lockout is the weak part of your bench, then doing partials at this joint angle will improve your bench. If your weak point is off your chest, then doing partials at the joint-angle around your lockout will not effect the rest of your lift. This is a big part of the westside system.

yea 15 degrees… problem is things complicate when you realize that isometric contraction and strenth is VERY different from dynamic strength (there are some over laps though).

Guys, Thanks a lot. I was in class and the professor spit this out at the class and I shot my hand up. Problem was I didn’t have the research in hand so there was no way I was right as far as the professor was concerned.

Tony,

The reasoning behind your benching example is practical, but doesn’t necessarily hold true. When you improve the strength at the lockout, it doesn’t improve the strength at the bottom when the weight is coming off your chest.

This is where I got confused because I knew there was a transfer to other joint angles but I also knew that the transfer didn’t apply in that manner. Your bench will improve overall, but only due to improving the weakest point in the kinetic chain. Make sense?

bigrob, check out the medx site and you can find some studdies. but I must say your response to tony was wrong (to a degree). If you just improve your “skill” at locking out you are correct that there will be little if any transfer, but if you improve the STRENGTH of the muscle there will be transfer thru the exercise. But partials are much different then isometric work.

Dunhill,
Thanks for the heads up, but one question: In your reply are you referring to partials or isometric work? My question centers around isometric work. I agree that partials will have a transfer to most other joint angles.