Muscular activity pattern for skilled performance and during learning of a horizontal bar exercise.

Abstract

Abstract A simultaneous recording of the electrical activity of some of the superficial muscles of the trunk, arm and thigh was made during the performance of the single knee circle mount on the horizontal bar. Changes in the pattern revealed by the recorded electromyograms ( E.M.G.) of two twelve-year-old schoolboys during a three-month period while the exercise was learned were studied and compared with the pattern revealed by a trained gymnast. The E.M.G. of a fluent performance by the gymnast showed co-ordinated activity between the hip-knee muscles and the arm-shoulder ones. At the early stages of practice the E.M.G. of the schoolboys showed long duration of high bursts with much overlap between action of the different muscles. At the end of the training period the schoolboys performed the exercise fluently. Yet thoir E.M.G.'s showed that they did not reach the level of coordinated muscle activity shown by the trained gymnast. Histograms based on the recorded E.M.G. clarified the changes in the patte...