Acute Effects of Ankle Tissue Flossing on Countermovement Jump Braking Strategy and Passive Mechanical Properties Following Repeated Jumping Exercise

Effects of calf and ankle tissue flossing on countermovement jump (CMJ) braking strategy and local passive mechanical properties were examined after repeated jumping. Forty healthy male college students matched by CMJ height were randomized within pairs to the flossing group (FLOSS; n = 20) or control group (CON; n = 20). After 100 jumps from a 30 cm box, FLOSS received calf and ankle flossing, whereas CON performed identical ankle movements without flossing. CMJ braking-phase variables, CMJ and squat jump (SJ) performance, and lower-leg muscle–tendon properties (MyotonPRO) were assessed at baseline (T1), immediately postexercise (T2), and postintervention (T3). After Holm adjustment, significant group-by-time interactions occurred for braking phase duration (p = 0.015, ηp2 = 0.128) and braking rate of force development (RFD) (p = 0.012, ηp2 = 0.145), but not jump height or passive mechanical properties. From T2 to T3, FLOSS showed a greater decrease in braking phase duration and a greater increase in braking RFD than CON, with similar braking net impulse. However, these differences were not confirmed by ANCOVA adjusting for T2 values. These findings suggest a possible acute modification of CMJ braking strategy rather than improved jump performance or recovery. Integrating force–time, jump, and muscle mechanical measures may allow for more comprehensive monitoring of acute flossing responses.