I think that studying the effects of exercise on POIS symptoms is very interesting, especially because it seems very beneficial to people in the first stages of POIS, but then there is a point for some sufferers, when their condition worsens, in which they can't tolerate exercise anymore, and moreover, exercise makes them just as sick as sex. That was exactly my case, for many years exercise made my POIS symptoms completely disappear, but then I experienced a sudden worsening of the condition and now exercise triggers the same symptoms than sexual activity, but much more severe. It's as if something in me had shifted and now was stuck in a different state. I strongly suspect some kind of involvement of the adrenal glands here (as I experience extreme thirst for days after very light exercise, to the point of being dehydrated after drinking 12 cups of water per day), but I would love to hear the opinion of a doctor on this (there's much more info in my POIS diary, linked in my profile signature, if you're curious or interested).
Just a little suggestion, I think it would be nice if you could include both types of people in your study, maybe create two groups: POIS sufferers whose symptoms are relieved by exercise, and those who are exercise intolerant. Maybe in the first group some parameters could be measured before and after exercise once POIS symptoms are present, and in the second group, you could compare POIS symptoms triggered by sex with those triggered by exercise, since they seem to share a common cause or underlying mechanism?
In my case (not sure about others but I think it's common), C-reactive protein is a parameter that is becomes very elevated when POIS symptoms are present. Also, since tachycardia (that appears some hours, or even a day after exercise) seems to be a common symptom of POIS sufferers that have developed exercise intolerance, what about measuring in a blood test the levels of different substances that could cause this, like some catecholamines or electrolytes? (You'll know far better than me what to measure, I'm not a doctor).
I'm sure other more experienced forum members will come up with better ideas, but I wanted to share these suggestions too in case they can help. I personally am far more affected in my daily life by POIS induced exercise intolerance than by my adverse reaction to sexual activity (I used to love sports and now can't even move a few boxes around without feeling very sick). If you can figure out the reason behind our exercise intolerance, many of us here will be forever grateful
