As I've alluded to in the past, I used to be quite athletic before my current profession and medical discomforts transformed me into the... well... "well-rounded" specimen I am today.
During that athletic period I had little to no access to professional training or organized opportunities - it was more of "just something I did." As such my actual capabilities were very limited to that set of techniques I could conceive of and practice effectively on my own with no spotting or equipment. What resulted was a semi-gymnastic style of movement that lent itself especially well to climbing and cross-country running on rough terrain; particularly deep forest and beaches mounded with driftwood.
I lived in Washington State at the time and so had an abundance of my preferred environments to hone whatever craft I possessed. Or perhaps the craft and the environment only existed in tandem, and had there not been the one I never would have pursued the other. The climbing was a little more varied, lending itself well to either trees (90'-150'+ evergreens) or (sub-)urban structures. At my peak physical condition there were few places I couldn't get to so long as I could place at least 2 or 3 fingers on it in some fashion, or jump a reasonable distance (no more than about 2 meters down and/or 1 to 1.5m lateral depending on configuration). I was especially fond of rock-chimney style ascents and poles (anything 18" diameter or less, free standing or attached to some construction) for their speed and ease of use to gain access.
I had fleeting dreams of becoming an actual gymnast, but really my motivation was just to move: mind and body in perfect balance. Maybe to escape something, maybe for the thrill; probably a combination. Naturally I used this for absolutely nothing productive, and on occasion found myself narrowly escaping mischief of a more intense flavor than was my usual.
Fast forward a few years to my jotting down thoughts on a novel (still in the works) taking place in the semi-near future. Part of the setting involved the over-urbanization of some influential cities, to the point that there really was nowhere to go but up. Or to bring "up" down to where it was accessible, since foot traffic continues to be a phenomenal way of traversing most metropoli. The answer was the introduction of the "Gridway" - a series of walkways in parallel to sidewalks placed at 3 story intervals on building exteriors with occasional lifts and staircases. The result (in this fiction) was a range of 3 dimensional movement that played havoc with the local retail real estate markets (who'd pay for a street level storefront when you can overlook the bay?) and greatly augmented the mobility of the general populace. For safety and liability purposes the Grid-walks were all enclosed in chain-link mesh and reinforced with banisters and other supports, of course.
This gave rise to a new sport - "Railing." This being the act of traversing the exterior of the structures by climbing, grappling, and jumping; but primarily through a barely controlled fall clinging tenuously to some conduit or other (since they were strung during the Grid's construction to increase the service capacity of the municipality in terms of electricity, bandwidth, etc.), perhaps with the aid of a hook. A particular quirk of the protagonist was to be his penchant for going up instead, finding calm rooftops (the majority of which are still just as utilitarian) to overlook the city landscape from a removed perspective - a direct reference to my identical semi-adolescent activities.
This was long before I became familiar with "le Parkour," French for "freedom of movement." Videos of its practitioners (and those of similar disciplines such as Yamikasi [not Japanese, despite the sound], "Free running," etc.) have recently swept through portions of the Internet to bring what is sure to be a brief spotlight to the practice. To see what had been an intimate act and imagination writ large and even codified has been vindicating. I'd thought my hobby peculiar but not remarkable, and am now pleased with the level of interest it's garnering - short-lived or otherwise.
I should also clarify, I wasn't as good as many of these individuals are. But I wasn't far off, nor would it have taken much to get there. Now is a very different story - but I'm still working on that. In the meantime I'm deeply satisfied that I can look back to the time when agility and strength weren't in question and knowing that I made the most of it: it's gone now, but at least it was here, and here in force.