Skeletal Muscle Ultrasonography and Muscle Fitness Relationships: Effects of Scanning Plane and Echogenicity Correction

This study examines the relationships between ultrasonography measurements of skeletal muscle size and echo intensity (EI) with strength local endurance in a habitually resistance-trained population. Twenty young, healthy participants underwent imaging biceps brachii sagittal transverse planes extended field view (EFOV) technique. Linear regression was used to examine measures thickness (MT), cross-sectional area (mCSA), EI, corrected EI (cEI) each scanning plane for their associations (1RM curl) (4x failure @ 50%1RM). The strongest predictor 1RM MT (adj. R2 = 0.682) cEI 0.449), respectively. Strength (R2 0.661) EFOV mCSA 0.643) demonstrated positive relationship. Local 0.265) scan 0.309) negative No were shown uncorrected EI. While supports size-strength echogenicity-endurance relationships, fitness. These findings provide important methodological insights regarding ultrasound fitness relationships.