ABSTRACT
The EMG records were analysed by reference to the different phases of the swing as identified by the kinematic data. The signals recorded onto the FM tape were digitised at 1 kHz by a personal computer fitted with the WASP system. For each trial, a sample 2000 ms in length was digitised. The time of impact was determined from the sonic marker on the seventh channel. Analysis consisted of normalisation to 1500 ms, averaging and integration. More extensive analysis was performed on the data from the posterior deltoid muscle. The mean voltage of the signal between the onset of muscle activity and impact was calculated, and the signal was integrated over this time period. Mean voltage scores were compared within subjects among distance conditions for evidence of ‘scaling up’, while the duration of muscle activity was expressed as a percentage of the total movement time and compared among the different conditions for evidence of temporal proportionality.
