Ultrasound estimates of Achilles tendon exhibit unexpected shortening during ankle plantarflexion.

ABSTRACT: The purpose of this study was to investigate Achilles tendon (AT) length changes during a series of tasks that involved combinations of higher/lower force, and larger/smaller length changes of the medial gastrocnemius muscle-tendon unit (MTU). We sought to determine if common ultrasound-based estimates of AT length change were consistent with expectations for a passive elastic tendon acting in series with a muscle. We tested 8 healthy individuals during restricted joint calf contractions (high force, low displacement), ankle dorsi-/plantar-flexion (DF/PF) with the foot in the air (low force, high displacement), and heel raises (high force, high displacement). We experimentally estimated AT length change using two ultrasound methods, one based on muscle-tendon junction (MTJ) tracking and on

SUBMITTER: Matijevich ES 

PROVIDER: S-EPMC8777463 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature