Comment on: Indirect Assessment of Skeletal Muscle Glycogen Content in Professional Soccer Players Before and After a Match Through a Non-Invasive Ultrasound Technology Nutrients 2020 12(4) 971

摘要

San-Millán and colleagues [ ] present data on muscle glycogen content captured by ultrasound technology. Although a simple, noninvasive technique is attractive, we question the validity of this approach. MuscleSound converts pixilation intensities in ultrasound images to a score of glycogen content based on muscle water content. In our view, there are no experimental or theoretical bases for such a link. We acknowledge that pixilation intensity may be related to muscle water content, and that glycogen particles have an osmotic effect on intracellular water. However, the athlete’s hydration status affects muscle water content independently of glycogen [ ]. Furthermore, glycogen-depleting high-intensity exercise is accompanied by an osmotically driven increase in muscle water due to accumulation of intracellular lactate ions and metabolites [ ]. The manipulation of muscle creatine content may also affect water content [ ]. In all cases, as is relatively common in sport, glycogen and water content change independently or in opposite directions.