Muscles in max (again)


hi people, im thinking of doing some kind of project on muscles in max. i see there a lot of discussion on using ‘stretchy bones’ it seems interesting but i do not know how effective it is really,

i was wondering if anybody has used the tools within max such as physique, bulging and tendons in order to work with creating muscles? is it effective, realistic, is it slow and boring?? is it just a pile of rubbish??

oh yes, and has anybody apart from Paul done anything with these stretchy muscles? and do you need to maxscript with them?


Stretchy bones aren’t just for muscle deformation. It’s often used to correct the deformation of the geometry around problem areas. To correct movement of the back, shoulders, and hips.

The design of the character will tell you what extra deformations it needs. Is it fat? is he/she strong? or is it a toony style of character.

There are a lot of threads here on this topic. Just search for it.


Kees, alongside Puppetshop, has released a seperate product called Skin FX, which handles Muscles/Skin deformation.

Skin FX’ is a 3dsMax based modifier (deformer) that gives the artist the ability to simulate mesh being deformed or ‘sliding over’ other objects such as skin sliding over bone or muscle. Skin FX can also help to control ‘volume loss’, which is a common problem with regular skinning techniques.

Taking advantage of parametric objects, Skin FX will make it possible to simulate effects such as skin sliding at very little performance cost.

  Skin FX can be used for many types of effects from: 

Muscle deformation to foot prints in snow to faking soft-body deformations.

Finally, Skin FX is an artist driven muscle and skin deformation plug-in. It is not a scientific muscle simulation tool. Instead it gives artists the control and workflow they need to take the next step in skin deformation.

There are also other commercial products like CATmuscle, Hercules, etc that are designed for muscle simulation under skin.



Are you angry with him? :slight_smile:


I’ve used the stretchy muscles to varying degrees of success.
Like Mustan9 said, it’s got a lot to do with what you need them for. If you’re going for hyper-realism, they can help quite a lot. I’ve used mine as stated to help with problem areas… backs and hips and inner thighs and throats.

They’re really simple to setup, and worth the minimal effort to get them looking and moving right to test and see how they might work for you and your workflow.


I’m definitly not the only one but I do use them alot. I just added 38 of them to a rig this morning.


Stretchy bones modeled up like muscles with flex added to them + SkinFX is working well for me


Really? Can you tell us how to do effective but simple stretch bones without all of the scripting? Like the spine tutorial in Max, is all that scripting actuall needed?


Anything you can do via script you can do by hand.
It just sometimes takes much much longer that way…

Even though I wrote SkinFX, I still use a combination of stretchy bones and SkinFX.
Sometimes stretchy bones are just as good and anything more complicated is just overkill.

Stretchy bones don’t give you sliding/wrinkling etc though, that’s where you need something like SkinFX or another muscle plugin. Plus with stretchy bones, the vertices are still being deformed around the pivot point of the bone, which is not always as good as having the vertices stick to the faces of the muscle.



interesting, so what advantages does this manual stretchy bones method have over a plugin that will do it for you in no time?? obviously one advantage is the price…


Kees tool is not a stretchy bone making tool it is a skin sliding tool. The really can’t be done effectively with max script.


Hey PEN, so all I need is one stretch bone lets say arround the upper arm muscle area? Can you please post a simple pic?


There is a tone of reference on how to make stretchy bones on the forum here just poke around a bit. Also my DVD’s cover this in great detail.

  1. Create two dummy objects.
  2. Create a bone between the two objects (keep the end bone).
  3. Enable stretchy on the bone.
  4. Position constraint the first bone to the first dummy object.
  5. Position constraint the second bone to the second dummy object.
  6. LookAt constraint the first bone to the second dummy.

That’s it.

You may need to create an up vector control object to prevent the bone from flipping around if you rig it on an arm.


I ordered the box set two days ago. :thumbsup:


Well I hope that you get lots out of it. I really look forward to the day that I can get another series done. I think that after the project I’m on I’m going to book off about a month from projects and jsut go nuts, I just don’t know when this project will be done at this point.


Thanks. I got it working already, so I place it in on the arm and have it facing the way of the muscle?


stretchy bones are really great, IF they do little twisting around the model. i’m rigging a human model now, and i’m able to rig almost every part using stretchy bones, twist bones and skin morph to fix some volume issues, but there’s one ugly part in human body called …

shoulder. seems like there’s no hell of a way to set up this thing right. i’m not happy if it looks right just with arm lowered or reaching forward. i’m trying to hit some extreme poses like:

palm holds opposite shoulder;
arm raised, shoulder raised (palm is above the head)
palm touching back (at the point as high as normal man can)

in all of these poses it’s really hard to get that deltoid muscle deform well and blend in into other muscle groups nicely. if it keeps shape well in one pose, it looses volume in another. it definitely won’t work with one stretchy bone, i always use at least two for muscles that are twisting or bending, but there’s so many different muscles attached to shoulder area, it seems nearly impossible to get that area work right.


indeed the shoulder gives me also trouble for weeks on my model.
I’ve seen the effective performance of the stretchy bones but i’m using biped and I cannot mirror those “muscle bones” very well, also in the skin modifier the mirror does’nt works on other bones manualy made (that are not created by the biped sistem), even mirrored with bone tools and renamed properly… what I’m doing rong ?


There is no reason that skin will not work on regular bones, you must not have them mirrored correctly is all that I can think. You can mirror bones perfectly with the Bone Mirror tool in the bone tools dialog.