Welcome to the labyrinthine world of Paralympic classification.
It is a complex system of grouping athletes by disability, designed to ensure that skill, fitness and power decide Games results rather than impairment.
Here’s a guide to the rules that govern when and where Britain will dig for gold in Tokyo.
Visually impaired athletes compete in the 11-13 classifications. Those in 11, like Libby Clegg, double T11 gold in 2016, run blindfolded with a sighted guide.
Paralympians with cerebral palsy and conditions causing involuntary movements compete in 31-38. The 31-34s, like defending T34 champion Hannah Cockroft, compete sitting and 35-38 standing.
Jonnie Peacock, Aled Davies and those competing with a prosthesis are in 61-64, classes added in 2017.
David Weir and athletes with impaired muscle power or range of motion are classified in the 51-17 category.
The prefixes T and F are added to indicate whether the athletes compete on track or on field.
Athletes able to use a standard bicycle compete in classes C1-5. This includes impairments in the limbs, impaired muscle power, and conditions causing involuntary movements.
The higher the number, the less severe the limitation. Dame Sarah Storey will aim to add to her 14 Paralympic gold medals in the C5 class.
Visually impaired riders compete in tandem with a sighted âpilotâ in Class B. There are also handbike and tricycle courses.
Classes 1 to 10 indicate a physical impairment, the higher number indicating a more serious limitation. Classes 11-13 are for the visually impaired and 14 for the visually impaired.
Ellie Simmonds and Maisie Summers-Newton are ranked S6 in Freestyle, SB6 in Breaststroke and SM6 in Individual Medley, for short or amputees.
There are a number of S14 swimmers competing for the GB Paralympic Games who have an intellectual disability causing sequencing and memory difficulties which impact performance. They include Bethany Firth, Jessica-Jane Applegate, and Scott Quin.
Players are awarded points from 1.0 to 4.5, relating to impairments. The higher the number, the less severe the limitation. Teams of five can only have 14 points on the field at any one time.
There are seven classes, ranging from 0.5 to 3.5. 0.5 athlete significantly impaired shoulder, arm and hand movements and 3.5 athletes have excellent arm and hand strength.
Alfie Hewett, Gordon Reid and Jordanne Whiley compete in the Open division for those with substantial loss of function in one or both legs. Quad athletes like Andy Lapthorne have three limbs affected by loss of function.
There are five categories for athletes with physical and visual impairments grouped together. The lower the score, the more severe the limitation. Defending champions Lee Pearson and Sophie Wells compete in Grade II and Grade V.
Classes in the sport of throwing range from BC1 to BC4, with all athletes competing in wheelchairs. BC1 athletes have severe leg, arm and trunk limitations and depend on a power wheelchair, while BC4 may have progressive weakness or amputations.
Paddlers compete in kayaks, propelled by a double-bladed paddle, or va’as which are outrigger canoes propelled by a single blade. They are then ranked from 1 to 3 based on limitation, with a lower number indicating more severe impairment.
Ten classes of physical impairment cover SC1, for those with no seated balance, up to SC10 athletes with mild limitation such as a stiff ankle. Will Bayley is SC7, with SC11 for the intellectually disabled.
Physically disabled triathletes are ranked from PTS2 to PTS5, with lower classes reserved for people with more severe limitations. Lauren Steadman and Claire Cashmore go head-to-head in PTS5. Visually impaired athletes swim, tandem bike and run with the same guide.
There will be six classes for the sport’s debut at the Games. WH1 and 2 are intended for athletes requiring a wheelchair, while SL3 and 4 are intended for standing athletes with impaired legs and gait. SU5 athletes have an arm impairment and SH6 are short.
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