Sunday, September 9, 2012

Static Contraction Workout

I did my fist workout with my new toy today (see previous post).  I did a triceps extension, a upright barbell row and a front lateral raise all with the ez curl bar attached to the chain (and a static hold pull up without the chain).

To sum it up in a word - surprised.  I've been doing static hold/contractions with weighs recently and figured this would be similar.  Not so much.  It felt very different.  I had to chew on why this was for a bit until I figured it out.  Let me explain what I came up with by taking the same movement, let's say the triceps extension, and breaking it down for each of the methods.

First is the weighted triceps extension.  In this exercise I put 40 lbs on the bar, raise it into the maximum moment arm position (elbow at 90 degrees) and hold it there until my muscles fail and the bar lowers.  No matter how long it takes to get to failure, I'm always exerting 40 lbs of upward force on the bar in order to keep it still (I aim for a weight which causes failure in roughly 90 seconds).  

Weighted triceps extension
At the start of this exercise, I'm capable of exerting more than 40 lbs of force, but choose not to ... otherwise the bar would go up.  In this way, I bide my time knowing my muscles will find it increasingly difficult to hold the bar in place.  The end result, of course, is failure and the bar comes down.  Exactly what I'm aiming for.







Second is the chained triceps extension.  In this exercise I find the right chain length to put the bar in exactly the same position as the weighted extension and then pull upwards on it until my muscles fail and I can no longer exert upward force.  Let's assume that I also want to do this in roughly the same amount of time (90 seconds).  Unlike in the weighted extension where I have to exert exactly 40 lbs of force at all times in order to keep the bar from moving, in this situation I can vary how much force I exert while still pulling upwards.  The graph below shows you roughly how I felt the force distribution of my triceps extension played out today.  Now, mind you, other than the zero at the failure point, I'm just guessing as to the actual upward forces I exerted (and the time really).  What's important, though, is the very different curve that resulted.  After a slow build up of about 25 to 30 seconds, I tried with all of my might to rip that eye bolt out of the board, and because the force was so high at this point, I had much more room (in force lbs) to come down from.

Chained triceps extension
The difference you can see between the two graphs explains why it felt so different.  Although the end goal of failure was reached in both cases, I was used to applying a very consistent force throughout the entire static hold.  However, having a buildup followed by a sharp rise and a relatively rapid decline felt, well, different.

Was it better or worse?  I don't know.  I guess I hadn't really though all of this through before hand and it caught me by surprise.  In my next effort, I believe I'll try to more evenly distribute my force throughout the rep, but I don't think I'm going to necessarily try to emulate the constant force applied in the weighted exercises.  Perhaps I'll just try not to pull (or push) so hard right after the build up phase so I don't have so 'far to fall' on the other side of the curve.  It'll be fun to play around with this.

Another thought regarding this topic is that it's probably easier to teach somebody static holds to failure with weights rather than with immovable objects.  With the weights there can be no 'cheating'.  That is, in order to keep the bar at the same position, we KNOW what the force applied has to be.  In the chained case, you could actually bounce up and down with your applied force and still have the chain remain taught.  I could easily see a newbie tackling this backwards and try to chase a time under load rather than muscle failure.  It's probably more intuitive to hold a weight in place with all you've got until it drops.

And here's the super bonus thought for today.  If Work is defined as Force times Distance, then technically speaking, static hold/contraction exercises produce no Work since the Distance traveled by the weight is zero.  Thusly, we can correctly call this type of training the No Work Workout

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