Subscribe by Email

Your email:

Coach's Questions

Send in your question and we will connect with an expert or two to get you an answer!

Whats New At Rogers Athletic?

Get Strong

Current Articles | RSS Feed RSS Feed

A Little Physiology

Akt/mtor/p70(s6k) signaling in human skeletal muscle                                                 

                                 

describe the imagemTOR (Mammalian Target of Rapamycin) is a key signaling pathway in muscular development.  It is regulator of cellular differentiation, that is, the process by which a less specialized cell becomes a more specialized cell type, and cellular size. TOR is the when and the where of cellular growth.

In adult skeletal muscle, increased mechanical stimuli exert a specific activation of the mTOR pathway.  This specific activation of this pathway is not the same as attained by the normal life mechanical processes of stimulation that occur in our youth.  Thus, it has been proposed that external mechanically induced tension plays a critical role in the regulation of skeletal muscle mass. 

A muscle is always in a state of passive tension there is no true resting state.  When there is a stretch or a pull or a perceived stress, the body responds by changing the tension state.  Increased mechanical stimulation in the form of tension is a powerful stimulus toward protein synthesis in skeletal muscle.  It takes systematic, progressive stimuli to elicit the adaptive hypertrophy process. 

Muscular tension is solicited through strength training and the greatest muscular tension is obtained through eccentric contractions.  Tension triggers protein synthesis.

What is interesting is that the velocity of the contraction is independent of the tension triggering response.  Slow and fast eccentric contractions cause the same growth response.  Fast eccentric and slow eccentric contractions augment the pathway the same way. 

tension1

 Pendulum Combo Pull multiple ways to Get Strong

Comments

something to consider regarding slow/fast eccentrics is that performance is typically a result of concentric muscle action, and will be heavily influenced by preceeding eccentric actions. a slow eccentric will not improve concentric force but a fast eccentric can. 
 
 
 
Think of a tennis ball, you can not drop it slow and have it come up faster/higher, but if you drop it faster it can come up higher/faster.
Posted @ Sunday, January 29, 2012 3:58 PM by JD
Post Comment
Name
 *
Email
 *
Website (optional)
Comment
 *

Allowed tags: <a> link, <b> bold, <i> italics