Handheld Ultrasound Parameters of Lower Limb Muscles versus Bioelectrical Impedance Analysis Parameters for Skeletal Muscle Assessments in Arabic Female Adults

Ultrasound (US) is a promising tool for skeletal muscle assessment; however, US studies have scarcely focused on Arabic populations. This study examined the association of handheld US indicators and bioelectrical impedance analysis (BIA) parameters in healthy Arabic females. A cross-sectional study was conducted on 60 healthy Arabic females whose muscle thickness (MT) and cross-sectional area (CSA) of the rectus femoris (RF) were measured alongside their MT and pennation angle (PA) of the medial gastrocnemius (MG) muscle (both muscles on the dominant side). Anthropometric and body composition analyses quantified fat-free mass (FFM) and appendicular skeletal muscle mass (ASMM). Muscle strength was assessed using a handgrip dynamometer, and physical activity levels were recorded with the Global Physical Activity Questionnaire (GPAQ). The CSA of the RF and the MT of both the RF and MG correlated significantly with FFM and ASMM. The PA of MG showed no significant correlations with ASMM, FFM, or handgrip strength. The CSA of RF was significantly correlated with handgrip strength (r = 0.313, p = 0.015), while the PA of MG correlated positively with GPAQ score (r = 0.346, p = 0.007). The CSA of RF significantly predicted both ASMM (beta = 0.883, p = 0.0002) and FFM (beta = 1.935, p = 0.0001). In conclusion, handheld US parameters, especially the RF's CSA, correlate with and can predict BIA-based FFM and ASMM in healthy females.