Push Rim Wheelchair Road Racing Classifications
The following system is used for push rim wheelchair road racing at the Boston Marathon. The Open Class is composed of Classes 3 and 4, and the Quad Class incorporates Classes 1 and 2.
Classification systems are developed by analyzing the sport, and they reflect differences in movement between athletes who have or lack the function of key muscle groups.
Function systems also take into account the relative importance of various muscle groups in performing. For example, it may not be critically important whether a push rim wheelchair road racer has finger flexion if quadriplegic athletes with and without active finger motion use the same backhand technique. Functional classification systems are still developing, and existing systems are analyzed and revised as necessary.
Class 1: May use elbow flexors to start (back of wrist behind pushing rim). Hands stay in contact or close to the pushing rim, with the power coming from elbow flexion. The old technique is to use the palms of the hands, pushing down on the top of the wheel in a forward direction.
Anatomical capability: Have functional elbow flexors and wrist dorsi-flexors. Have no functional elbow extensors or wrist palmar-flexors. May have shoulder weakness.
Class 2: Usually use elbow flexors to start but may use elbow extensors. Power from pushing comes from elbow extension, wrist dorsi-flexion, and upper-chest muscles. Additional power may be gained by using the elbow flexors when the hands are in contact with the back of the wheel. The head may be forced backward (by neck muscles), producing slight upper-trunk movements.
Anatomical capability: Have functional elbow flexors and extensors, wrist dorsi-flexors, and palmar-flexors. Have functional pectoral muscles. May have finger flexors and extensors.
Class 3: Have normal or nearly normal upper-limb function. Have no active trunk movements. When pushing, the trunk is usually lying on the legs. Usually use a hand-flick technique (or friction technique) for power. May use the shoulder to steer around curves. Interrupt pushing movements to steer and have difficulty resuming the pushing position.
Anatomical capability: Have normal or nearly normal upper-limb function. Have no abdominal muscle function. May have weak upper-spinal extension.
Class 4: Have backward movement of the trunk. Usually have rotation movements of the trunk. May use trunk movements to steer around curves. Usually do not have to interrupt the pushing-stroke rate around curves. When stopping quickly, the trunk moves toward an upright position. Use abdominal muscles for power, particularly when starting but also when pushing.
Anatomical capability: Have back extension, which usually includes both upper and lower extensors. Usually have trunk rotation (i.e., abdominal muscles).