That is pretty neat. I’d have to see/use it to truly understand it, but I kinda get it.
In curls my sticking point is usually at the bottom. I’ve torn (minor tears, not like full sproing/shred) a couple of times, but I’m pretty sure the was on the negative, about mid way.
How would you define what the problem is?
I wasn’t trying to answer that. I was telling him about a machine that does what it’s advertised. It just tied in nicely because it has the option to manipulate resistance curves. I could tell you, definitively, that when you load for peak contraction on that machine, you will burn out more quickly than any other setting on it. Like I said a few posts back - the arm is a lever, so when you load it in a position where there’s little leverage - like bent as much as possible, where the bicep peak would be - you can’t move as much weight with it for as long as you can in the mid-range position.
There are two questions that muddy the waters with this, though - one, is the force you can produce necessarily the same as the “strength” of the muscle you’re contracting or is it just a result of levers, and two, which I’ve now said about 3 times, is the strength of a muscle in a certain position necessarily tied to the effectiveness of building that muscle?
Very good points! On your last one, wouldnt it have to be? To effectively build the MOST muscle, dont you have to train it thru the strongest part? If we agree contracted is for the curl, would bottom 1/3 of a curl build most muscle?
Nope, not necessarily. It could be the case - I’m not saying which part is the best part to train it, but I’m saying there’s a lot of differing opinions on this. One of the cornerstones of DC training is weighted stretches, which Dante swears by for hypertrophy. I also brought up incline bicep curls, which a lot of people swear by, and has the bicep in a stretched position. Straight legged deadlifts have the most load in the stretched position. Dumbbell flyes have the same feature. That’s why my opinion is, for hypertrophy, to hit stretched, mid range, and peaked.
True, different muscles have different points. One thing, Dante got that stretching from John Parillo who introduced fascia stretching in the 80s or 90s. The idea was to stretch the fascia(painful stretches at times) to allow the muscle more room to grow. Muscle is contained within the fascia. Very interesting stuff way back then
Here, analyze this. Aside from being kinda fat and needing a haircut. 
I made it about a month ago when another poster piqued my curiosity.
So I worked up to failure then dropped back. There is a little english on them, but no grindy squirming to get underneath it like when we were kids.
Not at all. The old-school notion that getting stronger is required to stimulate more hypertrophy has been shown over and over again to not be The necessary be all end all, it’s merely the simplest way for a beginner to track a variable that is easy to see.
There have been multiple pathways documented to trigger proteins synthesis, via a more metabolic approach, simple mechanical tension, you name it. The point is, while bodybuilders may use heavier weights than the average person in the gym, strength does not keep increasing on a never ending pathway. That’s why sequencing of specific exercise orders, performance adjustments, pre-exhaust, all sorts of solutions exist to stimulate muscle growth without worrying about moving an ever increasing resistance through space.
(As an anecdotal, most of the more advanced trainers I know, focus a lot more on training through the weaker, or in the case of bicep curls here, stretched position, and avoiding the “stronger “portion, as it can minimize the actual tension despite allowing you to move or hold more weight)
S
He was probably wrong about that.
Here is why I say that:
The latest thinking, science-wise, is that hypertrophy is triggered by exposing muscle fibers to high mechanical tension. High mechanical tension develops in a muscle when loading conditions are such that all the available muscle fibers are forced to be recruited, and maximum cross bridging develops. That occurs in two ways: you are lifting a really heavy weight, close to your 1 RM, or your muscles are thoroughly fatigued, so that you are forced to recruit whatever unfatigued muscle fiber remains in order to produce any movement.
The key part of the above is “maximum crossbridging”. That occurs when the muscle is contracted at about the mid range position. That is when you have the highest degree of overlap between the myosin and actin filaments. At the extremes of movement (very shortened or very stretched), there is less overlap and hence less opportunity to form cross bridges. The thinking is that this variation in myosin/actin overlap explains why the muscle tension versus length relationship looks the way it does (see the earlier graph posted by j4gga2).
==Scott ==
If I recall I first asked a simple question, what do think is the strongest position of a curl and for some reason you can’t seem to answer that? I simply wanted your opinion, nothing more.
== Scott==
Once again thank you Average Al. This stuff is over my head but right or wrong it’s the kind of response I was looking for !
I am going to say standing with an EZ curl bar (for me). I think it is a mechanically advantageous position (curling with arms out front would be the least) and there is probably some momentum brought into the curl from the standing position, regardless of how strict you try to be.
== Scott ==
So you almost got to saying which is the biceps curl strongest position . You said the stretched position is the weakest so what do you figure is the strongest, mid way or fully contracted?
Thanks
I’d love to try that Strive machine!
Scott
After reading what everyone has said, it seems like the Bicep and Arm is in the strongest position at 90 degrees, or half-way bent. That’s where arm wrestlers like to be, not extended and not all the way contracted. That’s the arm angle for folk style wrestling like half nelson’s. Or if you were carrying a big ass muddy rock and you didn’t want to get your shirt dirty you would lock your elbows at 90 degrees, and pin them to your sides to carry the rock out in front.
But when you do “standard” curl, like standing barbell, that halfway up position is where resistance is greatest. So your arm is “strongest” but the curl is “heaviest.” Then you keep curling, raising the barbell up. You bicep goes into a weaker position, but now your forearms are stacked under the bar, there is less torque (like angular force) on your arms and less force against your biceps. Even though your “bicep” is in weaker position, your “Curl” is in a stronger position.
Jagga already showed the bell shaped Strength Curve for length vs strength of your bicep.
These graphs show the resistance curves for different types of curls.
Moving your elbow position around changes where you get the least/most force or weight in the curling motion.
Arthur Jones was “right,” it’s good to get your elbows Up to work the bicep peak, like in preacher curls or Arnold curls or spider curls. But elbow up, bicep shortened is Not the strongest position for your bicep, and it’s Not the most important part of the ROM of a curl. And it definitely Not the only way you should train your arms.
And if you raise your elbow up, in front of your body to pre- shorten your bicep, then lock your elbow in place, and then stretch it out in that position it’s easy to fuck up your bicep tendon. So be careful!
Good answer! Thanks.
Scott
I go all out for my Squirrel Bro!
Wheres the graph from?
Oh, sorry dude. From this article.
The standing barbell curve sucks! Next to no resistance at the bottom, then crazy resistance in the middle, followed by next to nothing at the top.
I go back to my favorite curl: Use a Scott bench, have it tilted steeper (close to 75+ degrees). Get an EZ-curl bar and a moderate weight on it. The weight you add going forward is accommodating resistance with chains.
This is easiest done with 20lb chains. For best results use cord of a fair amount of length when making the chain into a loop. Fully extended the chains would work on squats and usually bench press. Wrap them around a few turns so that a small amount of chain is off the ground and a small amount remains on the ground at the contracted position to keep the chains from swinging.
I would work up to 4 pairs of chains. The 25lb bar had a pair of 25lb plates to start.