To investigate the effect of an active stretching program on the knee flexors with regards to flexibility, torque, and functional mobility of older women. The hypothesis of this study was that a program of active knee-flexor stretching increases flexibility and muscle torque and improves functional mobility.Twelve active older women aged 68.3 ± 6.2 yrs participated in this study, which lasted 12 wks. This study was divided into three phases (A1-B-A2), each lasting 4 wks. Phases A1 and A2 were control phases (without intervention), and phase B (stretch) consisted of seven repetitions of active knee-flexor stretching (1 min each, 30-sec rest, twice a week). Flexibility, functionality, and isokinetic torque (knee flexors and extensors) were assessed by measuring the knee-extension range of motion, the "Timed Up & Go" test, and by a dynamometry test at 60°/sec.Stretching increased the flexibility of the knee flexors (41.5%; P = 0.0001), knee-flexor torque (11.4%), and extensor torque (10.1%) (P ≤ 0.01) but decreased Timed Up & Go test performance (14.3%; P = 0.0001).The results of this study showed that an active stretching program was effective in increasing the flexibility of knee flexors, extensor and flexor torque, and functional mobility in older women.