A total of 32 adult Wistar albino rats was divided into four groups. The first three groups received 1000 impulses of 0.15 mJ/mm2, 1500 impulses of 0.15 mJ/mm2, and 2000 impulses of 0.20 mJ/mm2, respectively. The last group was kept as the control group. Subsequently, Achilles tendons were harvested for histological studies from all rats at the 3rd week after a single application of ESW.