Former professional golfer Tommy Armour is credited with inventing the term yips to describe a combination of psychological and neuromuscular factors that forced his early retirement from competitive golf. A number of other veteran golfers have also struggled with the yips, most often in short putting situations under pressure. The condition is described as involuntary twitches of the hands or lower arms that cause golfers to shank simple putts. The yips often occur right at the moment when the clubhead meets the ball, causing the putt to go to one side of the hole.
Experts in both sports psychology and sports medicine are still not sure what causes the yips, but several theories have emerged over time. One theory is that they are triggered by the psychological pressures surrounding an important golf shot, such as a game-winning putt. The combination of a public audience, a significant cash incentive and the adrenaline rush of competition can cause a golfer to lose focus during a putt. Many professional golfers report this reaction during games in which the stakes are very high.
Another cause of the yips may be primarily neuromuscular in nature. Some studies on the body mechanics of professional golfers show a tendency to assume awkward putting positions for extended periods of time. A fast putting surface with a left-to-right break near the hole, for example, may require the golfer to grip the putter at an extreme angle. Holding this position throughout the entire putting stroke could trigger a muscle spasm or cramp at the critical point of contact.
Although the yips are generally associated with the small motor skills of a putting stroke, some golfers also report incidents of 'driving yips' during their earlier power game. One form may cause a golfer to suddenly turn the face of a driver out during a tee shot. Although some critics of the theory ascribe these twitches to poor golfing techniques, nearly half of all professional golfers have reported at least one inexplicable incident of the yips.
The yips are not limited to the world of golf, however. Other sports involving intricate hand and lower arm coordination under pressure, such as basketball, also have their forms of the yips. Former professional basketball player Charles Barkley is said to have suffered from a form during crucial free throws and other precision shots. Some baseball players also experience uncontrollable twitches at the moment of contact between bat and ball. Players who become psychologically affected by the yips may seek treatment with sports psychologists and sport medicine clinics.
People in other professions outside of sports may also be affected by the yips. Musicians who must maintain awkward fingering positions throughout a performance have been known to experience the yips. Dentists and surgeons who work for long hours with hand-held instruments may also experience a form. Incidents of writer's cramp or musician's cramp may also be attributed to the same muscle spasms associated with a golfer's yips.