Effect of Instrument-Assisted Soft Tissue Mobilization on Gastrocnemius Stiffness and Ankle Range of Motion

Participants will receive a single session of instrument-assisted soft tissue mobilization (IASTM) applied to the gastrocnemius muscle using a stainless-steel instrument. The treatment consists of longitudinal and transverse strokes targeting both the medial and lateral heads of the muscle. The procedure will be performed by a trained clinician, following a standardized protocol lasting approximately 5 minutes. The goal is to induce mechanical and neuromodulatory effects on muscle tissue. This intervention is designed to assess acute changes in muscle stiffness (via shear-wave elastography) and ankle dorsiflexion range of motion (via the weight-bearing lunge test).