Passive resistance of hamstring muscles in children with severe multiple disabilities?

The purposes of this study were to evaluate whether resistance to stretch c ould be measured in a reproducible manner from day to day in children with severe multiple disabilities, and whether 6 weeks of daily activity, includ ing one daily stretch, would modify passive resistance to stretch. Passive resistance to stretch was measured in six children using an established mod el that synchronously and continuously measured knee flexion moment (Nm) an d EMG activity of the hamstring, while the velocity and angle of a static s tretch was controlled. Resistance to stretch was evaluated in the absence o f EMG; activity. Measurements were taken on two separate occasions with a 2 -week hiatus, and before and after a 6-week activity period which included a daily 1-minute static stretch. There was no significant change in resista nce to stretch when tested a weeks apart (test 1, 8.6 +/- 1.2 Nm; test 2, 8 .3 +/- 1.2 Nm, p > 0.05) which yielded a strong correlation coefficient (Sp earman r = 1.0, p < 0.01; Pearson r = 0.953, P < 0.01). Similarly, there wa s no difference in resistance to stretch before and after the B-week period (mean difference 0.22 +/- 0.75 Nm, p > 0.05). Data from this study demonst rate that resistance to stretch of the hamstring muscle group could be meas ured in a reproducible manner from day to day in children with multiple dis abilities. Further, resistance to stretch was unchanged after 6 weeks of da ily activity, including a daily 1-minute static stretch.