Shear Wave Elastography in Children: Normative Values and the Impact of Healthy Habits in a Cross‐Sectional Study

Objectives Biomechanical properties of the musculoskeletal system are important to understand muscle function, but they are difficult to assess noninvasively. Shear wave elastography (SWE) allows objective quantification of muscle elasticity. However, normative data and the influence of lifestyle habits on muscle elasticity in children remain unclear, particularly across multiple upper and lower limb muscles and in relation to modifiable healthy behaviors. The main objective was to assess muscle elasticity at rest and during maximum passive stretching (MPS) in children using SWE, and to address existing gaps by evaluating multiple muscles from both limbs, as well as to evaluate the influence of lifestyle factors, with particular attention to healthy habits. Design and Methods SWE was used to measure the elasticity of the biceps brachii, pronator teres, adductor longus, lateral gastrocnemius, and soleus in 44 typically developing children (mean age 8.9 years; range 3–14 years; 27 females). Measurements were taken at rest and MPS. Data included anthropometry, physical fitness, Mediterranean diet adherence, moderate‐to‐vigorous physical activity (MVPA), and sleep duration, allowing the exploration of lifestyle‐related determinants of muscle elasticity. Results Reliability estimates exceeded 0.91, indicating excellent consistency. SWE values increased with higher Mediterranean adherence during MPS in all muscles, while at rest, an inverse relationship appeared in biceps and pronator teres. Sleep time was negatively associated with SWE at rest and positively adductor longus during MPS. MVPA showed some associations without consistent patterns. Conclusions SWE is a reliable and objective technique to evaluate muscle elasticity in typically developing children. By providing multi‐muscle reference data from both upper and lower limbs and demonstrating associations with diet and sleep, this study extends current pediatric SWE literature beyond feasibility and reliability. These findings suggest that SWE could help quantify the physiological impact of healthy habits on muscle properties during childhood.