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Why Can You Lift More During Eccentric?

Ok, here is a question.

Why can you use more weight during the eccentric phase of the lift? Like, whats the biological reasoning behind it?

I’m curious.

it’s not biology, it’s physics

From my understanding you can lift more from the eccentric muscle contraction because it acts as a protective mechanism in response to muscle overload in conjunction with shock absorption and quick changes of limb velocity.

Drury, DG; The role of eccentric exercise in strengthening muscle. Orthop Phys Ther Clin North Am 9:515, 2000.

Smith, LK. et al.,: Brunnstrom’s Clinical Kinesiology, ed 5. FA Davis, Philadelphia, 1996.

Other Studies have shown that it could also be due to resistance from the stretching of noncontractile tissue in the muscle.

Dean, E: Physiology and therapeutic implications of negative work: a review. Phys Ther 68:233, 1988

[quote]jehovasfitness wrote:
it’s not biology, it’s physics[/quote]

yes sir. It is simply because when lifting, you need to exert a force greater than the force on the object due to gravity (in order to get it to move in the direction against gravity). When lowering an object, you can exert a force that is LESS than the gravitational pull exerted on the object.

During the eccentric phase, you only need to exert enough force to keep it descending in a controlled manner, but you don’t have to actually exert any force to make it move… gravity should take care of that for you!

dan

[quote]Hadow Khan wrote:
Ok, here is a question.

Why can you use more weight during the eccentric phase of the lift? Like, whats the biological reasoning behind it?

I’m curious.

[/quote]

You are not lifting a weight in the eccentric phase, you are controlling it. You are slowly letting gravity overcome you. You are not trying to overcome the gravity.