Changes in Muscle Hardness from Resting to Mid-Range Lengthened Positions Detected by Shear Wave Elastography (SWE) with a Novel Protocol of Ultrasound Probe Placement

Muscle hardness and its relationship with different muscle lengths/positions are important for understanding underlying physiological status, yet remained unclear. This study aimed to detect the local at lengths identify influence of position on in healthy adults. A total 26 adults participated this study. Shear wave elastography (SWE) was used measure Rectus Femoris (RF), Tibialis Anterior (TA) Gastrocnemius Medialis (GM). Each tested both resting (RST) mid-range lengthened (MRL) positions. novel ultrasound probe placing method introduced, applied, evaluated Moderate excellent intra-/inter-rater reliability (Intraclass Correlation Coefficient, ICC ≥ 0.70) found measurements. The significantly increased from RST MRL all three muscles (p < 0.001). that position. TA GM could also be sensitive enough reflect age-related changes hardness. highlights importance assessed extremities an appropriate consistent when assessing qualities by ultrasonics clinical practice.