**Updated :** <https://bretcontreras.com/do-we-even-need-to-lift/>

Bret gets it. LOL

Regarding the small sample size. You do realize how common studies of less than 20 people are? Large RTC studies are obvious the best but unless big pharma's backing you it's tough to find the funding.

Just saw this part "Even if you do completely unloaded bicep curls you will still stimulate red muscle fibers."

* Type I - Muscle Fibers are Red due to myoglobin content / O2.
* Type IIa (are Red / Pink)
* Type IIx are (Pale / Whitish) as they are glycolytic.

> 
> **It is well known, that slightly loaded work stimulates the growths of red muscle fibers and myogenesis.**
> 
> 
> **I may be wrong but I believe Type I changes seen are more vascular and metabolically related. Do you have a study showing hypertrophy occurs in Type I fibers? I know that myofibrils / the overall number of sarcomeres increase with resistance training.**
> 
> 
> 

You're basically illustrating by accident why I find this study so interesting. What is inducing the hypertrophy? Are the IIx and IIa saying contacted for a sustained period? How?

Basically how are you getting to threshold to depolarize your largest muscle fibers? Sustained flexion I would think would have the opposite effect vs a normal isotonic concentric contraction. What's triggering this?

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Wow didn't expect to find this. A study released less than a year ago compared left vs right arm muscle mass changes with the following setup

* One arm no load (but maximally flexing muscle)
* Other arm high load training (70% 1RM)

After 18 sessions they found:

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**Increased muscle mass on both sides**  

*(with slightly greater gains on the heavy load side)*

In a way it actually makes sense:

**As muscle tension increases so does recruitment**   
*(or the number of active motor units)*

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*Size Principle:* Motor Units are activated from smallest to largest  

*Motor Unit:* Consists of a single motor neuron and all the fibers it innervates  

*Recruitment:* The number of motor units that are active.  

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> 
> Anyone every seen a similar study?   
> How would you explain the
> hypertrophy with a load?   
> Do any hormonal changes occur by just
> flexing?
> 
> 
> 

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**Source**

[The acute and chronic effects of "NO LOAD" resistance training](https://www.readbyqxmd.com/read/27329807/the-acute-and-chronic-effects-of-no-load-resistance-training)   
*Physiology & Behavior 2016 October 1, 164 (Pt A): 345-52*