Chang KV, et al. - Researchers investigated muscle quality and quantity in the elderly adult population groups with dynapenia but not sarcopenia. Using high-resolution ultrasonography, they measured echogenicity and thickness of the biceps brachii, triceps brachii, rectus femoris, and medial gastrocnemius muscles in community-dwelling elderly adults. Outcomes suggested that dynapenia without sarcopenia was associated with decreased thicknesses of the rectus femoris and medial gastrocnemius muscles. This association remained significant after adjustment for demographics, body composition, and physical performance. For evaluating dynapenia, ultrasound measurements of lower-limb muscle thickness can be considered an auxiliary criterion.