A Comparison of Motor Unit Behaviour in Young and Aged Subjects
SODERBERG, GARY L.; MINOR, SCOTT DUESTERHAUS; NELSON, ROGER M.; SODERBERG GARY L.; Physical Therapy Program, The University of Iowa; MINOR SCOTT DUESTERHAUS; Program in Physical Therapy, Washington University, School of Medicine; NELSON ROGER M.; Department of Physical Therapy, Thomas Jefferson University
Журнал:
Age and Ageing
Дата:
1991
Аннотация:
We evaluated motor unit behaviour in young and aged subjects during ramped tension development and release to 10% maximum voluntary contraction requiring 10 seconds to complete. Six young and six elderly adults performed isometric abductor digiti minimi muscle contractions while motor units were recorded with implanted fine wire electrodes. Computer interactive programs yielded interspike interval (ISI) data for 16 units from the young and for 15 units from the aged subjects. Mean ISIs for young were 88.4 ms for shortening and 96.5 ms for lengthening contractions. Units from the aged had ISIs of 110.5 ms and 117.1 ms for shortening and lengthening contractions. Some evidence for between-group differences in firing pattern during ascending and descending ramps was also found.
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