Validity and usefulness of hand-held dynamometry for measuring muscle strength in community-dwelling older persons

The aim was to determine the validity and usefulness of hand-held dynamometry for measuring muscle strength in independent community-dwelling older persons. Cross-sectional study was performed in 281 subjects aged over 65, mean age of 74.3 years. The strength of six muscle groups was measured in three consecutive attempts using JAMAR hand-held dynamometers. Individual values, maximums and means, intra-and inter-individual variability, test-retest reliability and concurrent validity with functional tests are described. The main results were: strength increased with each attempt for all muscle groups, suggesting technique learning, except for pinch and grip, suggesting muscle fatigability. Relative intra- and inter-individual variability was higher in women; it was lower for the pinch and grip strength. Test-retest reliability was very good and concurrent validity with functional tests was good. We conclude that hand-held dynamometry is valid and useful for determining functionality. It is recommended to perform three attempts for all strength measurements, except for pinch and grip, in which one is sufficient. (C) 2011 Elsevier Ireland Ltd. All rights reserved.