Objective: the aim of this study is to observe whether there are ultrasound changes between men and women in
the Achilles tendon at rest, at maximum passive force is applied and during walking.
Material and methods: it was a cross-sectional study involving 27 healthy young participants recruited as volunteers between April to July 2022. A variety of data was recorded: (age, Body Mass Index, sex, smoking, current
injury status, allergies, medications, previous surgeries, type of sport, and number of weekly workouts) and
ultrasound measurements at rest and at passive force (Cross Sectional Area Achilles Tendon length, tendon
thickness, Cross Sectional Area and pennation angle of the soleus muscle to the Achilles Tendon).
Results: women demonstrated a statistically significant lower proximal and median thickness both at rest (4.5 vs
5.1 mm with p < 0.001 for proximal thickness; 4.4 vs 5.3 mm with p < 0.001 for median thickness) as well as
during maximum eccentric contraction (4.3 vs 4.8 mm with p=<0.001 for proximal thickness; 4.1 vs 4.8 mm
with p < 0.001 for median thickness).
Conclusion: there are significant sonoanatomical differences in vivo Achilles tendon between men and wome
