Data supporting "What does myotonometry measure? Independent contributions of subcutaneous adipose tissue and muscle thickness to muscle mechanical properties"

This dataset supports the study “What does myotonometry measure? Independent contributions of subcutaneous adipose tissue and muscle thickness to muscle mechanical properties.” The study included 130 healthy young adults (82 males and 48 females) who underwent bilateral myotonometric and ultrasonographic assessment of five lower-limb muscles: rectus femoris, vastus medialis, biceps femoris, and the medial and lateral heads of the gastrocnemius. MyotonPRO-derived variables comprise oscillation frequency (F, Hz), stiffness (S, N/m), logarithmic decrement (D), relaxation time (R, ms), and creep expressed as the Deborah number (C). Ultrasound-derived variables comprise subcutaneous adipose tissue thickness (SAT, mm) and muscle thickness (MT, mm) measured at the corresponding anatomical sites. The data were used to assess bilateral symmetry, sex-related differences, and the independent and shared contributions of SAT and MT to variability in myotonometric parameters using hierarchical ordinary least-squares regression and variance partitioning. Participant identifiers have been replaced with non-identifying codes. The accompanying README and data dictionary describe the dataset structure, coding, units, and analysis-relevant abbreviations.Measurements were performed bilaterally in a temperature-controlled laboratory (22–24°C) after acclimatization and rest. Rectus femoris and vastus medialis were assessed with participants supine; biceps femoris and both gastrocnemius heads were assessed prone. MyotonPRO measurements were obtained in MultiScan mode as the mean of five consecutive impulses, with a coefficient of variation below 3%. Ultrasound measurements were acquired using a portable B-mode system (EBit 20, CHISON Medical Technologies) with a 5–12 MHz linear-array transducer. SAT was defined as the distance between the deep dermal border and superficial muscle fascia; MT was defined as the distance between superficial and deep fascia.The study was approved by the Bioethics Committee at the Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland (approval No. KB-1/2024). All participants provided written informed consent before participation.