Furthermore, there is only an optimal style for each individual, where style refers to the individual expression of a motor skill. This style has to be developed on the basis of observing and experimenting with the 'ideal' model until the person produces a central nervous programme which suits his or her body for a given action. Research by the Russian scientist, Yushkevich, supports these points. He analysed the symmetry of leg strength in sprinters and concluded that striving for full leg symmetry is inappropriate. Moreover, there are distinct differences in the patterns of asymmetry between novice, intermediate level and elite athletes.
Dorsiflexion is stronger in the push-off leg of all athletes, except novices.
Interestingly, leg strength asymmetry was found to increase as sprinters increase in proficiency, reaching a peak among intermediate level athletes, then diminishing again as level of sports mastery increased. Yushkevich maintained that 'asymmetric exercises destabilise the space-time characteristics of motor acts, thereby helping athletes break speed barriers'. There is an ancient injunction that the weavers of Eastern carpet must include at least one flaw in their work to recognise that perfection is reserved for the Divine and not for humans. They usually developed these while becoming proficient at thier particular sport and the injury could not reasonably be related to them. I feel the same about orthotics-athletics that have not had a problem for 20 years and then develop one that is temporarily relieved by changing the stress with an orthotic should not need to continue its use for the remainder of their lives.