Muscle Architecture

This study is a randomised controlled pilot trial designed to evaluate the feasibility, safety, and preliminary efficacy of a 12-week resistance training intervention in children aged 10-14 years. The study adheres to the CONSORT extension for randomised pilot and feasibility trials and incorporates key elements of the SPIRIT guidelines for clinical trial protocols. The primary purpose of the study is to assess feasibility-related outcomes and to generate effect size estimates to inform the design of a subsequent fully powered randomised controlled trial (RCT).

Percussive massage therapy (PMT) is widely used in therapeutic and athletic settings, but its effects on muscle architecture are not yet fully understood. This study aims to examine the acute effects of PMT applied to the plantar flexor muscles on the muscle architecture of the medial and lateral gastrocnemius muscles in healthy adults aged 18 to 30 years. Participants will be randomly assigned to either a PMT group or a control group. Ultrasonographic assessments will be performed before and after the intervention to evaluate muscle thickness, pennation angle, and fascicle length. The findings of this study may help clarify the acute effects of PMT on muscle structure.

Achilles tendinopathy is a frequent overuse disorder caused by repetitive loading of the tendon, particularly observed in athletes and middle-aged men. It is typically characterized by mid-portion pain, stiffness in the morning, and functional limitations, with structural alterations such as thickening and disrupted collagen alignment. Chronic progression often compromises performance and quality of life. Eccentric training protocols, such as the Alfredson regimen, are commonly prescribed but their standardized nature does not fully address individual variability. Alternative approaches including Heavy Slow Resistance training and progressive loading models (e.g., Silbernagel protocol) have demonstrated clinical effectiveness and higher patient adherence, yet they still apply uniform loading across the triceps surae without accounting for architectural differences. Given the heterogeneous structure of the soleus and gastrocnemii, targeted loading strategies may be required to optimize tendon adaptation. To address this, the present study employs a muscle architecture-based exercise program tailored to the functional and structural properties of each muscle. Ultrasound imaging will be used to evaluate muscle-tendon morphology, while isokinetic dynamometry and functional performance tests will quantify outcomes. Pain (VAS) and functional capacity (VISA-A) will also be assessed. This randomized controlled trial aims to compare the effectiveness of an architecture-specific program with the Alfredson protocol on tendon remodeling, strength, endurance, functional performance, and symptom reduction in individuals with non-insertional Achilles tendinopathy.