T Nation

Motor Units?


#1

Is it true that over time if you stick with the same exercise, for example the bench press, your body will adapt and will start using less and less motor units to accomplish this movement with that amount of weight? And if this is true, since you are using less motor units would this cause a plateau in that exercise, causing you to switch the exercise so your body has to relearn again and it would increase your motor units once again? If this don't make since and you can't answer it here is a simpler question. What would the point in switching an exercise from the bench to something else if in powerlifting that is the only type of bench you do (Flat Bench Press)?. thanks for any help


#2

it's called SAID:

Specific Adaptations to Imposed Demands

Overload - A given level of stressor produces adaptation to that level. Further improvements require higher stressor levels.

Specificity - Adapatation to a given stressor is quite specific to that stressor, and may not transfer well to other stressors.

You can get around this by changing tempo, % of RepMax, or the exercise itself


#3

If you stay with the same weight - yes it sounds plausible. if not - I dont think so. there is in terms of muscular overload a point of diminishing return when using the same excersize(according to tsatsuline, staley and others) but not in skill(proprioception and pattern learning)or neural adaptation(MU recruitment either inter muscular or intra muscular) AS FAR AS i KNOW.

the big boys will have their opinion here Im sure

S-man.


#4

Motor unit recruitment is relative to the % of 1RM being lifted. As you progress on a movement your 1RM will go up for that movement. If you are still using the same weight, it will now represent a lower % of your new 1RM and your body will not need to recruit as many motor units to lift it.


#5

Don't trust anyone from Regina.

(just kidding).

Melville Millionaire.....


#6

So, if I'm trying to increase my bench I don't really need to change to a different angle or anything, just change up my amount of repetition, sets or percent of weight in order to keep my motor units recruitment high.


#7

Generally speaking, the heavier the load the more motor units will be recruited. Explosive movements with lighter loads also recruit lots of high threshold motor units (plyometrics, sprinting etc.). If you are trying to increase your max bench you should spend most of your time training with heavy weights and low reps with long rest periods. Speed work will also help. This does not mean you shouldn't change variables such as bench angle and grip width periodically as well. Just as the body adjusts to training with the same weight over time, it will also adjust to a set movement pattern.

TheSmileCreator: It's good to see I'm not the only one on here from SK. Do you know if there's any more of us around?


#8

Check out this article by Dave Tate.
http://t-mag.com/html/body_115b600.html
It has some good info.

Although I haven't read it I'm sure his Eight Keys article has info you could use as well.

Dance


#9

Read up on the Conjugate method and Westside Barbell.........