What exactly is slacklining?
Slacklining is a balance sport practised on a stretchy, synthetic webbing line (about 2.5cm-5cm wide) which is fixed between two points. “Slack“, of course, means the opposite of “taut“ and this tells us that the line has a certain amount of “give“ .

Slacklining is a kind of dynamic balancing which is very different from balancing on a taut steel cable (static balancing). Because of the dynamic properties of the web, instead of remaining in a single position to retain balance, one has to keep reestablishing it by constant movement in a variety of positions. Setting up a slackline is simplicity itself and can be done almost anywhere.

Where does it come from?
The development of slacklining is closely linked to the legendary Camp 4 in the Yosemite Valley and the climbing scene there. It was in the 1960s that climbers started to pass their leisure time by balancing on barrier chains. In the early 1980s, Adam Grosowsky came across this new pastime, which by this time had become widespread there, when he visited the camp. Back in Olympia, Washington, he and his friend Jeff Ellington started experimenting with climbing ropes. They then moved on to be the first to rig a tubular band of the kind used in climbing, and that marked the birth of slacklining as we know it today: the art of balancing on stretchy, flat, synthetic webbing. Although it is no longer possible to trace the terms “slackline“ and “slacklining“ back to a particular person or point in time, it is clear that they represent the logical progression from terms like “slackchain“ and “slackwire“. “Slack“ has stayed with us whereas “chain“ and “wire“ have given way to the new medium, the “line“. For a long time, until about 2006, the sport was confined largely to Camp 4 and the climbing scene in general, but since then, interest in the sport has spread and slacklining enthusiasts are to be found all over the world. Key factors in this growth of interest include media exposure, the merging of individual local groups, and the ever-increasing number of slackline meetings and events as well as the appearance on the market of various complete slackline kits and the availability of slacklining courses. Altogether, the last few years have seen a meteoric rise in the sport which shows no signs of diminishing.

What are the different forms of the sport?
Basically, the sport can be divided into two main groups: lowlining and highlining, the difference being in the height at which the slackline is fixed.

A LOWLINE is a slackline that is fixed at a height you can jump from and this is what is generally meant when referring to a slackline.

JUMPLINE/Trickline: this is usually a relatively taut lowline of about 10-15 m in length. The trampoline-like qualities of the the line makes jumps and combinations of jumps possible. Flips and a variety of static tricks including yoga-like poses also belong to an experienced trickliner's repertoire.

LONGLINES are slacklines fixed over greater distances. However, there is no official cut-off point where a slackline becomes a longline. Generally speaking, any slackline longer than 50m would be referred to as a longline. The challenge of longlines lies in the huge variation of swinging modes of the line depending on one's position on it (near the anchor points, the line oscillations are short and hard whereas in the middle there is much more “give“ allowing the line to move further and more slowly). Longlines also require greater concentration, focus and motivation not to mention physical stamina. Setting up a line gets more complicated and more dangerous the longer it is, as the preset tension equals several tons (max 2-3t) and would release tremendous forces if the line were to tear.

An interesting variation of the slackline is the so-called WATERLINE. As the name suggests, this is a slackline set up above water. One difficulty it shares with a highline is that of visual orientation in space. Unlike grass or sand, however, the surface of water is reflective and it moves. This gives a false visual impression and misleading information about one's actual position and balancing thus becomes considerably more difficult. This is what makes waterlining particularly attractive.

HIGHLINING is the most extreme form of the sport. The line is no longer fixed at jumping height but at dizzying levels above ravines, between treetops or rocky outcrops. Highlining is a specialist area that requires a high degree of expertise not only where moving safely on the slackline is concerned, but also in the mastery of materials and methods of securing oneself on the line. Traditionally, the highliner is attached to the line by a so-called highline leash: a length of climbing rope is usually tied to a harness while steel rings are secured to the other end and threaded onto the line and thus follow the slackliner as he moves. Essentials for highlining include the safe rigging of the line which must incorporate back-up and sufficient excess, and proficiency at line catching (the term used for catching the line to avoid falling unrestrained on the leash). Mental training is also indispensable.

The difficulty of highlining lies in its psychological aspects as well as in factors like materials and securing techniques. Just because a person has no problems moving on a slackline does not mean they are ready to try out their skills on a highline. One reason for this is the matter of orientation in space. An important factor that has a direct effect on balancing and orientation and usually makes both easier is the fixing of one's eyes on a point at the end of the line. There is, however, another factor that plays an important role here, namely peripheral vision, which is the visual perception of what lies beyond the area we can see clearly. On the highline, visual clues are few and far between: the highliner is surrounded by nothing but air and often there is not even a point at the other end of the line where he can fix his gaze. So highlining is a particularly demanding, difficult and, of course, dangerous variation of slacklining.

Source: www.slackline-tools.com