Normally, insects' muscles are attached to their exoskeleton but what happens to this attachment when they are moulting?
Sorry if this is an extremely silly question but I have wondered about it for a long time and have tried searching it.
You can find a concise answer here in a section from The Insects: Structure and Function by R. F. Chapman, eds. Stephen J. Simpson, Angela E. Douglas. 5th Edition. Cambridge University Press.
In essence the source says that the muscle attachment to the cuticle is maintained during the moulting process, while the new cuticle is formed under the old cuticle.
Connections to the new cuticle are formed at the same time as the old ones are broken.