76 patients with chronic ankle instability were randomized to one of four groups: joint mobilization, plantar massage, calf stretching, or control intervention with no treatment. Each group received 6 sessions over a 2-week treatment phase. Patients were assessed after 1 session and 6 sessions for data during single-leg stance on a force plate, including center-of-pressure distribution, velocity of center-of-pressure, and time-to-boundary minima. While significant differences and effects above minimum detectable changes were noted for center-of-pressure distribution and velocity of center-of-pressure after 1 session, including in the joint mobilization group with eyes open and eyes closed and in the massage and calf stretching groups with eyes closed, effects after 6 sessions were largely not significantly different to control intervention and were below MDC values.