I was coming down the corridor from the hotel restaurant when I heard the heavy breathing, sensed the clutching and thrusting, and turned to look. The curtains of a nearby room were pulled back, and there were two bodies, panting, sweating, writhing.
Yes, I was peering into the hotel gymnasium.
Gymnasiums have become another Pay-and-Display zone these days. They remind me of aquariums, with glass walls through which you can gaze and be attracted - or goggle and be appalled - by the exotic species inside.
I fall into the appalled group. As far as I'm concerned, exercise should be performed in private, or somewhere it won't frighten children and horses.
My reasons are partly aesthetic. Even the Body Beautiful doesn't look its best when seen straining to row a non-boat across non-water. And the Body Average would be better advised to row, row, row its boat gently behind closed blinds.
In most other environments, the expressions and exhalations of gym-users would bring a charge of Offensive Behaviour. Going back to that aquarium comparison, gym-junkies remind me of pufferfish - the ones who attract mates by inflating their chests, gaping with their mouths, flashing their gaudy flanks, and bobbing up and down on the spot.
I accept that gyms play a significant part in an executive's career. Being seen in the hotel gym in one's designer lycra is as important as being seen in the hotel lobby in one's designer vicuna.
But don't execs realise their gym routine of pedalling frantically while staying in the same place may not be the best image for an up-and-comer to present?
I suppose I shouldn't complain about fitness obsessives working out in gyms. It does keep them off the streets.
But have these people ever paused to think of the distress they cause? Distress not only to couch kumaras, but to those of us whose designer gym gear is last year's gardening shorts and a T-shirt reading VAMPIRISM SUX?
Actually, have such obsessives ever paused to think at all? Some of them seem living, gasping proof that fitness is only two letters away from witless.
I acknowledge exercise plays a hugely important part in one's life. It leads to those wonderful moments when you stop.
I'm also aware it has become a major growth industry. Fitness has fashions, and fitness MEANS fashion. Plus it's probably wiser to be seen wearing one's dayglo orange and green in the gym than to have it found concealed under street clothing if one has a traffic accident.
I accept, too, that a honed body leads to a honed mind, which leads to a honed career; that s/he who walks the treadmill becomes fit, focused and able to afford so many cars that s/he doesn't have to walk anywhere ever again.
But I still have my doubts over the public-parade nature of gyms, and I suspect I'm not alone. Surely there was a link between the sight of all that raw, strained, sweaty beef on the hoof in the hotel gym, and the near-empty adjacent hotel restaurant.
David Hill is a Taranaki writer.