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View Full Version : Do your negatives!- The Effects of eccentric exercise



HeavyDutyGuy
04-10-2010, 04:15 PM
J Appl Physiol. 1994 Sep;77(3):1439-44. Related Articles, Links


Decline running produces more sarcomeres in rat vastus intermedius muscle fibers than does incline running.

Lynn R, Morgan DL.

Department of Electrical and Computer Systems Engineering, Monash University, Clayton, Victoria, Australia.

Unaccustomed eccentric exercise, in which a muscle is lengthened while generating tension, is well known to cause injury and pain. A rapid training effect has been demonstrated in a number of eccentric exercises. The mechanism for both the damage and the training has been unknown. Morgan proposed that the damage is caused by sarcomere length instabilities during operation on the descending limb of the sarcomere length-tension curve and that the training effect is an increase in the number of sarcomeres connected in series in a muscle fiber, thus avoiding the descending limb (Biophys. J. 57: 209-221, 1990). We tested this proposal by exercising rats on a treadmill set at either an incline or a decline of 16 degrees, an exercise that has previously been shown to cause damage in untrained rats and a training effect. The vastus intermedius muscles were fixed and were digested in acid, and the fiber and sarcomere lengths of representative fibers were measured. From these measurements, the mean number of sarcomeres per fiber was found for the different training regimes. A clear and repeatable difference was found, supporting Morgan's prediction of more sarcomeres after decline running, although with some differences in response that depended on the age of the rats.

AnglicanBeachParty
04-10-2010, 05:39 PM
This blog post has been swimming around in my head for a few weeks now. Your post reminded me to actually write the thing down:

Eccentric vs Concentric Contractions for Spiritual Hypertrophy (http://hotrodanglican.blogspot.com/2010/04/concentric-vs-eccentric-contractions.html)

Baldiewonkanobi
04-10-2010, 06:56 PM
I try to do at least one grueling negative within each series of sets/bodypart. Years ago I tried to do 'negative days' but they drained me to the core. The two of you...thoughts on how many/how often??

Baldie

HeavyDutyGuy
04-10-2010, 06:59 PM
GP- cool blog post.
Bill- limited- to the last set of an exercise- and only on one or two exercises per body part. I think too much will overtrain you fairly fast. But one or two sets is golden.

AnglicanBeachParty
04-10-2010, 07:06 PM
I try to do at least one grueling negative within each series of sets/bodypart. Years ago I tried to do 'negative days' but they drained me to the core. The two of you...thoughts on how many/how often??

Baldie

I'm a novice at this. I'm about to begin with the so-called "DC" training, which uses slow negatives. It's taking a real mental adjustment.

I saw somewhere, from Dante (the originator of DC training) that he pictures the only purpose for getting the weight to the top of the motion being so that he can lower it slowly in the negative phase. So far, I'm not having much success retraining my brain to think this way!

Baldiewonkanobi
04-10-2010, 07:25 PM
ABP...I believe that Dante has you eating like a NFL lineman for recovery. DC will knock the Dogg Crapp outta you. You will need your Testosterone at optimum and break out the check book for food....net results a larger
:hypno: PAUL :hypno: look out!!!
Baldie

D_T
04-10-2010, 09:17 PM
DC has evolved a bit over the years. I don't think he intended to put quite as much emphasis on the negative as people interpreted. You should be in control of the weight but I don't think he wants an 8-10 second eccentric portion.