Previous studies have measured testosterone activity in men and its Provitazol relationship to exercise. These studies support the idea that a moderate amount of exercise creates more testosterone (which in turn ratchets up the sex drive); they have also suggested that long and grueling workouts can tend to erase the increase in testosterone and may contribute to a decrease in testosterone (and, subsequently, in sex drive). Instead of looking at testosterone changes, this study decided to ask men directly about their sex drives. The questions asked men about not only how often they had sex but how often they thought about sex, and how intense their thoughts were, and the like. After taking into consideration all pertinent factors (age, overall health, etc.), a pattern emerged. Those men whose exercise routines were on the moderate or light side in terms of intensity and/or duration tended to have moderate or high sex drives. And men who worked out like maniacs, pushing themselves to the limit, tended to have low sex drives.
As mentioned earlier, the number of participants is a little small to be able to draw any solid conclusions. In addition, these are all men who volunteered to take the survey, which is to some degree intrusive; there could theoretically be different results if those who declined to take the survey had answered the questions. Perhaps more problematic is that measuring sex drive in a self-reported manner presents challenges. Despite efforts to quantify it, one man's interpretation of how intense their sex drive is may vary from another's. And even with an anonymous survey, it's very easy for a man to "cheat" a little, especially when admitting to how often he has had sex or thinks about it.
Still, the results do raise interesting points. If a man pushes himself during his workouts and exercise routines and does find that he has a decreased sex drive, he might want to take his exercise intensity down a few notches and see if there is a difference. Or he may want to talk to his doctor to see what other alternatives he could consider.