Role of perceptual and motor abilities in instep-kicking performance of young soccer players.

The present study made a dynamic analysis of the ground reaction forces developed on the supporting foot during instep kicking to investigate the relation between specific perceptual and motor abilities and the performance of this skill. 45 young soccer players (11-13 years of age) participated in a series of laboratory tests assessing simple, choice, and discrimination reaction time, sustained attention, depth perception, and sense of kinesthesis. Kicking performance measured by the amount of impulse (calculated as the integral of force) developed on the supporting foot during kicking. There was a significant correlation of the kicking impulse with choice reaction time (r = -.54) and attention reaction time (r = -.41). Stepwise regression analysis indicated that choice reaction time accounted for 29% of the variation in the anterior/posterior kicking impulse and 16.4% of the variation in the medio/lateral kicking impulse. The significant relation between kicking impulse and measures concerning speed of information processing suggests that processes associated with fast response selection may play an important role in instep-kicking performance. These findings can provide useful information for designing of training schemes and testing protocols.

Perceptual-motor contributions to static and dynamic balance control in children.

The authors addressed balance control in children from the perspective of skill development and examined the relationship between specific perceptual and motor skills and static and dynamic balance performance. Fifty 11- to 13-year-old children performed a series of 1-legged balance tasks while standing on a force platform. Postural control was reflected in the maximum displacement of the center of mass in anterior-posterior and mediolateral directions. Simple visual, discrimination, and choice reaction times; sustained attention; visuomotor coordination; kinesthesis; and depth perception were also assessed in a series of perceptual and motor tests. The correlation analysis revealed that balancing under static conditions was strongly associated with the ability to perceive and process visual information, which is important for feedback-based control of balance. On the other hand, when greater task demands were imposed on the system under dynamic balancing conditions, the ability to respond to the destabilizing hip abductions-adductions in order to maintain equilibrium was associated with motor response speed, suggesting the use of a descending, feedforward control strategy. Therefore, like adults, 11- to 13-year-old children have the ability to select varying balance strategies (feedback, feedforward, or both), depending on the constraints of a particular task.