T Nation

Strongest Position of a Curl?

Recently I’ve talked about books relating to certain curl machines and specifically about the strongest position of a curl or any other exercise for that matter . Some say the muscles strongest position is the contracted position , others say the opposite. For now without dragging studies into this what is your opinion on this ??

Wouldn’t this be an easy thing to set up and test?

1 Like

For an isolated curl, I have felt that my bicep got stronger as it contracted. I therefore did Scott curls with chain accommodating resistance.

  • The lockout of many exercises is the easiest part of the movement.
  • Most upper back pulls the latter part of the rep is the most difficult.
  • Many free-weight exercises, the geometry and gravity determine the place during the rep that is most difficult.
  • Squating has a really nice feel with accommodating resistance (with chains, bands, or both). The lockout being easy with free-weights only.

I prefer free-weights over machines. I don’t like the friction that compromises the negative or the lack of stimulation on the stabilizer muscles.

I ask for your opinion, not an experiment.

I would assume its strongest at the contracted portion, simply from a mechanical advantage in terms of leverage compared to almost extended.

Of course this means nothing in terms of stimulating new muscle growth.


The length-tension relationship dictates that any muscle is strongest when slightly shorter than its “middle” length

This, however doesn’t take in to account individual leverages for each muscle, or the physics of the exercise you perform.

IIRC, all the elbow flexors have their best moment arm for elbow flexion at ~90°, but I’m not certain


It feels like the last quarter or so.

But, if the muscle is moving the same weight through the least mechanically advantageous part of the range of motion, the. I’d say it is there that it is creating the most tension, or strongest.

So it depends on what your definition of is is.

Let me now add this and please tell me
what you think.

Jones believed the maximum growth potential was at the biceps maximum contracted position

How would you test it?

When you’re doing heavy curls and you begin to fail, the first thing that happens is you can’t make it all the way to peak contraction.

The reason many machines are built to modify resistance curves is to lower the resistance slightly at the fully shortened portion of the exercise, where you are often not as strong. The arm as a lever simply can’t produce as much force when it’s all the way bent.

That depends if you think maximum growth potential has to do with strongest position. Some people swear by incline bicep curls where your biceps are stretched and absolutely in a weaker mechanical position.

I have always made sure to focus a portion of my bicep work on that peak, though.

If we’re talking strictly what I believe, although I’m not doing much direct arm stuff these days (apologies bro gods), I think the bicep workout that’ll produce the most growth is going to involve an exercise that focuses on peak contraction, a mid-range exercise like vanilla BB curls, and a loaded stretch like incline bicep curls.

Figure out what weight I could pickup/move at what range :man_shrugging:

This is exactly why I don’t like machines. I always have had the thought lingering in the back of my mind that “Yeah, it says X, but what was it really?”.

1 Like

I think @FlatsFarmer posted about Strive machines before - my machine has 2, just a tricep extension and a bicep curl.

If you put your plate in the middle, it’ll emphasize the middle portions, and the pegs at the ends will make it either heavier in the stretched or heavier in the contracted position. I don’t use them much, but they’re pretty cool, and then you can load plates in 2 positions, etc. Anyways, it’s a machine that, by manipulating where you place the plates, you IMMEDIATELY feel that portion of the curl get 2x harder and everything else get easier. Definitely does what it’s advertised to do.

1 Like

But was Jones right? One would think contracted. I think contracted

Yeah, but that doesnt answer the question/solve the problem. Just provides even weight

1 Like

Uhh, what?

This is all so confusing


You’re telling me - I was just showing @skyzyks an example of a machine that does what it’s advertised to do.

I thought this was a simple question anybody who’s ever done any type of curls/ever picked something up in life could answer, but I’m starting to question things like maybe his question is something other than what he’s asked/I’ve interpreted

But which is the strongest part? The strive machines are great. You can make whatever part harder by adding more weight. Equal weight, what is the strongest part? You didnt answer that