Musculotendinous adaptations induced by training and competitions in high and low performance triathletes.
Triathlon; Achilles tendon; Triceps sural; Ultrasound
Triathlon is a sport that is growing worldwide. Along with this growth, we find a series of injuries primarily associated with the running discipline, with calcaneal tendinopathy being a prominent injury in this scenario, as this structure is heavily stressed both in running and cycling. Although there are a considerable number of studies that have evaluated the architecture of the triceps surae muscles and the Achilles tendon in athletes from various sports, as well as their positive and negative adaptations, and characteristics that may be associated with better performance or predisposition to injuries, we did not find studies specifically investigating these tissues in triathletes. Understanding the architecture of this tendon and the muscles that compose the triceps surae in this specific population is important to clarify the structural changes that occur and are related to performance and injury alterations in these structures. Ultrasound presents itself as a standard examination for evaluating these structures due to its quality, portability, and real-time information. Objective: The present study aims to identify the musculotendinous adaptations in the Achilles tendon and muscles that compose the triceps surae induced by triathlon training and competitions in high-performance and lowperformance athletes that may be related to injury predisposition, as well as explain the differences in sports performance between the groups. Methods: Twenty highperformance triathletes, twenty low-performance triathletes, and twenty physically active, healthy males will be screened through anamnesis to define the research groups that will be part of the study. Pain and function of the Achilles tendon will be measured using the VISA-A scale (Victorian Institute of Sport Achilles Assessment). The structure of the Achilles tendon and the muscle architecture of the triceps surae will be assessed by ultrasound. The reliability of the ultrasound measurements will be obtained by evaluating the images of the individuals using the intraclass correlation coefficient.