ORIGINAL ARTICLES   

The Journal of Sports Medicine and Physical Fitness 1998 June;38(2):169-76

Copyright © 1998 EDIZIONI MINERVA MEDICA

lingua: Inglese

Reliability of isokinetic knee extension and flexion strength testing in elderly women

Capranica L. ¹, Battenti M. ¹, Demarie S. ¹, Figura F. ²

¹ Istituto Superiore di Educazione Fisica, Rome, Italy; ² School of Medicine, University of L’Aquila, Italy

Background. Inter­trial and ­test-­retest reli­abil­ity of iso­ki­net­ic ­knee exten­sion and flex­ion ­strength meas­ure­ments was stud­ied in eight­een eld­er­ly wom­en (­mean age 68±5 yrs), ­using increas­ing and decreas­ing angu­lar veloc­ity test­ing pro­ce­dures.
Methods. Experimental Design: five recip­ro­cal ­knee exten­sions and flex­ions at ­three dif­fer­ent angu­lar veloc­ities (90, 120, and 180 deg/sec) ­were per­formed by ­means of a ­MERAC appa­ra­tus on two occa­sions fif­teen ­days ­apart.
Measures. Data rel­a­tive to ­torque, pow­er and ­work ­were con­sid­ered.
Results. Statistically sig­nif­i­cant dif­fer­enc­es ­were ­found ­often ­among the ­five ­trials and intra­class cor­re­la­tion coef­fi­cients, rang­ing ­from 0.03 to 0.90 for exten­sor mus­cles; rang­ing ­from 0.44 to 0.89 for flex­or mus­cles, ­were ­shown ­among the ­best ­three out­puts. Peak val­ues ­were ­reached with­in the ­first ­three rep­e­ti­tions, ­though a 20% ­chance to pro­duce ­peak out­puts was ­shown in the ­last two rep­e­ti­tions. Increasing and decreas­ing ­test veloc­ity pro­ce­dures did not con­sis­tent­ly ­show sta­tis­ti­cal­ly sig­nif­i­cance for ­peak out­puts. Generally, for ­each iso­ki­net­ic param­e­ter high­er and ­more fre­quent­ly sig­nif­i­cant cor­re­la­tion coef­fi­cients ­between ­test and ­retest experi­men­tal ses­sions ­were ­found for ­peak val­ues (rang­ing ­from 0.36 to 0.80) ­with ­respect to ­mean val­ues (rang­ing ­from 0.22 to 0.74).
Conclusions. These ­data sug­gest ­that a ­test pro­ce­dure includ­ing ­five ­trials ­tends to ­increase the ­chance of pro­duc­ing the ­best ­peak out­puts. Furthermore, con­sid­er­ing the ­best ­peak and ­mean per­for­manc­es ­could be ­more appro­pri­ate ­when stud­y­ing eld­er­ly wom­en.