A perception-action coupling type of control in long jumping.

The authors' goal was to identify the control mechanisms used by long jumpers (N = 6) to precisely position their foot at the board. In addition to the intertrial method usually used in previous research, an original method based on a trial-by-trial analysis was also implemented. If the approach to the board in long jumping encompasses two distinct sequences separated by a key step that marks the initiation of visual control, then a trial-by-trial analysis should reveal those sequences, regardless of the amount of adjustment: The step number at which regulation is initiated should be the same irrespective of the amount of adjustment. If, in contrast, a perception-action coupling mechanism operates, then the step number at which regulation is initiated should be a function of the amount of adjustment: A linear relation between those 2 variables should emerge. The results of the present study are compatible with continuous control mechanisms based on a perception-action coupling.