Inline skating


Inline skating is a multi-disciplinary sport and can refer to a number of activities practiced using Inline skates. Inline skates typically have two to five polyurethane wheels, arranged in a single line by a metal or plastic frame on the underside of a boot. The in-line design allows for greater speed and maneuverability than traditional (or “quad”) roller skates. Following this basic design principle, inline skates can be modified to varying degrees to accommodate niche disciplines.

Inline skating is commonly referred to by the proprietary eponym “rollerblading”, or just “blading”, due to the popular brand of inline skates, Rollerblade.


The German branch of SKF developed and produced inline-skates in 1978 with wheels for hockey or for the street. The product was stopped after one year as the management did not want a consumer product in its portfolio.

Other inline skates were developed as a substitute for ice skates, Life magazine published a photo of American skater Eric Heiden, training for the 1980 Olympics, using such skates on a Wisconsin road.

In 1980, a group of ice hockey players in MinneapolisMinnesota were looking for a way to practice during the summer. Scott and Brennan Olson formed the company Rollerblade, Inc., to sell skates with four polyurethane wheels arranged in a straight line on the bottom of a padded boot. They sold the company in 1984 to Bob Naegele jr., who advertised to the general public and sold millions.


  • Athletes in Figure Skating must keep their performances varied. The Zayak Rule states that no participant can attempt triple or quadruple jumps on more than two occasions.
  • Judges may also mark down participants or disqualify them completely if they fail to adhere to rules and regulations for music and costumes. Certain types of music are not permitted, and costumes cannot contain “excessive decoration” or be considered as too revealing.
  • Athletes can also be disqualified for time violations.


For most skating a high boot is used, which provides more ankle support and is easier to skate in, particularly for beginners. Speed skaters often use a carbon fiber boot which provides greater support with a lower cut allowing more ankle flexion. For recreational skating a soft boot is used for greater comfort, but many other disciplines prefer a harder boot, either to protect the foot against impact or for better control of the skate. The boot may also contain shock absorbent padding for comfort. Downhill skaters often use boots that are heat-molded to the shape of the foot, with a foam liner.

Most aggressive skates use a hard boot or a hard/soft boot for increased support.


Typical recreational skates use frames built out of high-grade polyurethane (plastic). Low-end department or toy store skate frames may be composed of other types of plastic. Speed skate frames are usually built out of carbon fiber or extruded aluminum (more expensive but more solid), magnesium, or even pressed aluminium, which is then folded into a frame (cheaper but less sturdy).

Carbon fiber frames are expensive but generally more flexible, making for a smoother ride at the expense of worse power transfer between the leg and the wheels. In general, carbon fiber frames weigh about 160–180 grams. Recently, high-end carbon fiber frames with a monocoque construction have been introduced. They offer the same level of stiffness as aluminum frames while weighing only around 130g. Aluminum can weigh from 170 to 240 grams. Frame length ranges from 2 wheel framed freestyle wheels (used in aggressive skating) to around 230 mm for short-framed four wheel skates (used in most inline designs), up to about 325 mm for a five-wheel racing frame.

Axles, bearings and spacers

Ball bearings allow the wheels to rotate freely and smoothly. Bearings are usually rated on the ABEC scale, a measure of the manufactured precision tolerance, ranging from 1 (worst) to 9 (best) in odd numbers. The ABEC standards were originally intended for high-speed machinery, not skating applications, and do not account for the quality of steel used, which is very important for how long bearings last. While higher rated bearings are generally better in overall quality, whether they automatically translate to more speed is questionable. Since at least 2007, Rollerblade brand amongst others have begun using their own rating system. For instance, Rollerblade brand is currently using a SG1 to SG9 rating system, whereas TwinCam brand is using its own “ILQ” (InLine Qualified) rating system and Bones brand is using its own “Skate Rated” rating system.


  • International Inline Skating Association.


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Chad Hedrick

Derek Parra

Taïg Khris