Colossians 2:20-23

If with Christ you died to the elemental spirits of the world, why, as if you were still alive in the world, do you submit to regulations— “Do not handle, Do not taste, Do not touch” (referring to things that all perish as they are used)—according to human precepts and teachings? These have indeed an appearance of wisdom in promoting self-made religion and asceticism and severity to the body, but they are of no value in stopping the indulgence of the flesh.

-Colossians 2:20-23

There are still a few more things to look at in these few verses.  With regards to submitting to regulations, to do such a thing is to act as "if you were still alive in the world".  We are alive in Christ and people who are alive in Christ do not submit to regulations.  To submit to regulations in the way that Paul is talking about is something people do who are "still alive in the world".

Another thing Paul points out is that "These have indeed an appearance of wisdom in promoting self-made religion and asceticism and severity to the body".  So, the submitting to regulations only appears wise.  These things that are ultimately from humans (not God) and are with regard to temporal things (instead of eternal things) aren't actually wise but wise in appearance.  They are also things that have to do with more outward religious discipline-like things.

I think the key is what Paul leaves to the end: "but they are of no value in stopping the indulgence of the flesh".  Perhaps "stopping the indulgence of the flesh" is the initial goal in these things (submitting to regulations).  It might be easy to think that certain rules (worldly ones, of course) are extremely beneficial.  I can fall victim to it, thinking I'll try harder to be more and more godly.  Unfortunately, as much as I keep falling victim to it, it never works.

Paul begins these few verses by saying, "If with Christ you died to the elemental spirits of the world".  We have died with Christ and so we shouldn't be submitting to regulations.  People who die with Christ (and are alive with Christ) are ones who do not submit to these regulations.  Once again, we are brought back to the idea of being rooted in Christ and walking in him.  There are some different specifics to watch out for, but the heart of the matter is for us to remain in him and walk in him.