I think Water is making a good suggestion. I deal quite a lot with people who experience neck/shoulder tension. If that's the tension area in your case, ask yourself . . . Even after a good massage, why does the tension come back?
I work with Chinese principles and western herbs. And our understanding is that tension is rising from the conditions in the liver. Damned energies in the liver due to congestion/stagnation will put back-pressures up into the neck and head areas causing a number of problems, everything from neck tension to migraines/headaches, anger/frustration/impatience and even eye/ear/nose/throat problems.
Any of the moderators on these forums can sell you the extracts to help you relax these rising liver conditions (The Chinese call it Liver Yang Rising.)
Here's my suggestion:
Buy extracts of . . . Linden flower (for general relaxation)
Feverfew (if your tension creates headaches), Cramp Bark (if you tension extends to stomach tension), tansy (if tension is creating anger/temper/frustration), black cohosh (if tension is creating muscular neuralgia elsewhere in the body), scullcap (for general relaxation), camomile (general relaxant).
These herbs are not limited to those areas I mentioned. I just mean that you'll want to blend your extracts to give more attention to the one or more herbs that may apply to you. Mix them all and the body will get a nice rounded-out use for relaxation. You should notice considerable improvement in 2-3 days.
If you buy an extract of each (pick the ones that apply to your situation), be sure to use per instructions. There's a possibility you'll over-due it. Two ways to know when to stop is 1.when you quit getting a buzz from it. And 2.when you're relaxed enough to remove the neck tension. Always take a break from herb combos after 10 days.
Warning: The way I describe the use of these herbs is for symptomatic use only. What I mean is . . . If you happen to have so much stagnant congestion that there's hot/fire conditions showing elsewhere, the relaxant tonics won't address those. In that case you would need to have a thorough evaluation by your local herbalist/practitioner (That's my disclaimer! lol)