I work out 5-6 times a week and the days I take off seem more stressful - basically thinking I should work out. I realize rest days are important, but how do you recommend dealing with the assoc. stress?
I think the biggest concern I have with the question is that you are using exercise as a coping mechanism, so not exercising is adding to your anxiety. It's the same as using food as a coping mechanism, except it doesn't expand your waistband. So, my first response is to attempt to figure out where all this stress is coming from.
I suspect that several of these might be at work at any given time. Although there are some things you can do reduce the stress, or at least the perceived stress to a bearable level. I'm going to start with a big one, but it might help uncover other causes:
Planning: When you work out, you have a definite plan. You know what to expect, and its easy to clear your mind and get to the task at hand. It becomes relaxing to work. Is that the same at work and at home?
Many people I have worked with in the past who were always feeling stressed were in perpetual "firefighter" mode. In short, because they had no plan in place, they were constantly scrambling to try and keep the customer from getting fed up and leaving. That relationship is not enjoyable for either the client or the contractor. It takes effort to dig out of the hole, but if you take some time to set up expectations, reviews, and other defensive actions before delivery day, the customer will usually accommodate the transition.
Same thing with home life. The top three things that put stress on any marriage is communication, sex, and money (or lack thereof). Take time to get on the same page and work out a plan to correct the things that just are not working. While you are planning, make sure you set aside fun time and date time.
Once you have a plan, do it. Just the same as exercise. You know what to expect, the other parties know what to expect, and while things may be uncomfortable for a time they will at least be bearable.
What goes on in Vegas...: Don't let work spill over to home life, and vice versa. When you are at work focus what you need to get done. When you are at home, put work out of your mind. You'll never relax when you are constantly reliving the deadline hanging over you.
Same with major future events that are looming over the horizon. Essentially, plan and execute your plan, but don't keep reliving the major event. It's not here and there's enough to worry about today. You never know, the event may not ever happen.
I know the answer doesn't have much to do with fitness...
However, stress can adversely affect your health. Learning how to manage it, is quite important. You will never learn to relax if you don't manage stress. It's just as important to actually rest as it is to exercise.
Your symptoms lead me to believe you have a very stressful day job or even life. In other words, by taking a day off you are removing the coping mechanism that allows you to deal with your stress - so the stress has no way out!
If this is the case, I would recommend that you find the "root cause" of the stress and remove that.
I think the reason why your question causes so much concern is you admit that rest is important yet are still experiencing stress when NOT exercising.
Ask yourself if any of these apply.
I think this might be off topic for F&N. Have you considered seeing a friendly local therapist? Feeling guilty over not exercising 1-2 days of the week borders on a disorder IMHO.
If you do insist on giving in to your compulsion, I guess Yoga, light Tai Chi or something similar on those off-days could be good for you, while not hurting your restitution too bad?
Think about how focused you are during exercise, I for one am completed encapsulated in my sport when swimming or running. Constantly thinking how hard can I push myself, or can I run comfortably in those further miles. Basically what I'm saying is do something which suits you, if your mind is running at two hundred miles an hour then how do you feel about doing nothing? Are you the kind of person is wants to be totally focused a 100% of your time, even on days off? Then Zen meditation maybe what your looking for, it has the same mental commitment of working out, except its all in the head. However if you want to totally relax then go something a bit less demanding; casual computer games, talking to friends, spending time with a loved one (provided she makes you happy), etc. It all depends on how your mind works, I do believe some people are hard wired to be on the go all the time, while other are not. Just the way things are.