Macro EMG in healthy subjects of different ages.

The findings of the recently developed technique of Macro EMG in healthy subjects of different ages are described. The characteristics of the Macro motor unit potential which probably reflects the relative size of the whole motor unit are presented together with suggested normal data for the three muscles studied. An increase in size of the Macro motor unit potential was found with age, particularly after the age of 60 years. Possible factors determining the Macro EMG signal and the age related changes are discussed.