Stretching prior to physical activity has been shown to decrease several muscular performance variables in over a dozen studies. Although a wide variety of stretching protocols have been used in these studies, the dose-response of this effect is unknown. The purpose of this was to study document the change in isometric grip strength over 100 seconds of static stretching. A convenience sample of college students gave informed consent and were randomly assigned to a control group (n = 22) or a stretching group (n = 35). Subjects performed a warm-up protocol and determined maximum grip strength based on four measurements using a hydraulic hand dynamometer. Grip strength was tested 10 more times one minute apart, with the stretching group performing repeated trials of 10-second static stretches of the wrist and finger flexors. Grip strengths were expressed as a percentage of initial grip strength. Mean normalized grip strengths were analysed with a group by gender MANOVA (p < 0.05) and the patterns of grip change were modeled by best fitting functions. Mauchly’s test of sphericity was significant (p < 0.05), so the Greenhouse-Geisser adjustments were used. There was no significant effect of gender or interactions with gender, so the data were collapsed across gender. There was a significant (p < 0.05) effect for trials. The significant (p < 0.05) interaction of trials and group indicated that there was a greater decrease in strength in the stretching group than the control group. This difference was mirrored by a linear best fit (r2 = 0.60, SEE= 1.2 %) to the control group data, but a logarithmic best fit (r2 = 0.92, SEE = 0.7%) to the stretching group data. Mean grip strength in the control group across time followed a nearly horizontal linear trend, while the mean grip strengths in the stretching group declined in a logarithmic fashion to 88.8 percent with 100 seconds of stretching. Statistically significant (p < 0.05) differences in normalized grip strength between these two groups appeared after 40 seconds of stretching. Meaningful decreases in isometric grip strength (greater than 5%) following static stretching are likely to appear in young adults following 20 to 40 seconds of stretching.