Being physios, we tend to say PHYSIO is the best!!

Having said that, you will need to find a physio skilled at "motor control". The main research comes out of University of Queensland and Curtin University in Australia so an Australian-trained physiotherapist will be your best bet (sorry, i am biased!!)

Being a Martial Arts trainer, i am guessing that you use your big muscles way too much (rectus abdominus, obliques, lats, hamstrings, erector spinae, etc etc). The stiffness that you feel may be that these muscles squeeze indiscriminately across many joints. In doing so, they tend to "jam" up your joints and so the manipulation you do to yourself releases the pressure temporarily.

Physios are the experts are rehabilitation and exercise with musculskeletal problems - they will help you retrain the muscles which support each joint individually. These exercises will feel like YOU ARE DOING NOTHING. I say this because there will be no "burn" or immense effort. You must stay mentally strong while doing this because intuitively you will think you are not improving. I like to show people how a gentle contraction is much more powerful than a strong one (believe it or not!). That usually lets them know they are on track.

Anyway, let us know how you go!