We see more of a sensual rather than sexual aspect in the practice of the Naturist lifestyle. The senses certainly work much better without the restriction of clothing and this plus the knowledge that one has broken through a societal taboo could explain the joy and freedom that is experienced.
There is no doubt that we are sexual creatures and there is a natural instinct to regard the naked body of the opposite sex if only from a point of curiosity.
However we are also able to go beyond a mere instinct response.
Were it otherwise males would not be able to restrain the arousal response within a nudist setting, yet this restraint is clearly what is observed and experienced.
We transcend instinct when we accept and respond to agreed behavioral limits within a defined Naturist setting such as a clothing optional beach, a club or Naturist resort.
In a broader societal sense a monogamous state would not be possible otherwise.
All this goes to prove that the dominant sex organ in the human body is in fact the brain!
This is why Naturists can rightly claim that nudity does not equal sex.