A comparison of make and break tests using a hand-held dynamometer and the Kin-Com.

The assessment of muscle strength is a task performed frequently by physical therapists. The purposes of this study were to determine whether intrasession test-retest reliability differs between make and break tests and strength tests that do not require an assessor (eg., isometric Kin-Com test) and hand-held dynamometer (HHD) assessments. The elbow flexor strength of 32 healthy, female volunteers was measured under four test conditions: Kin-Com make and break, and HHD make and break. Two measurements were performed for each test condition by the same rater. The results showed: 1) measurements obtained using the HHD deviated from a normal distribution, 2) comparable reliability coefficients for the make and break tests were obtained from the Kin-Com device, 3) there was a higher reliability coefficient for the make test compared with the break test for the HHD tests, and 4) the measured forces for the break tests were higher than the make tests. The results support the premise that hand-held dynamometry is a viable alternative to more costly modes of isometric strength measurements, provided the assessor's strength is greater than that of the specific muscle group being measured.