Effects of Eccentric Single-Leg Decline Squat Exercise on the Morphological and Structural Properties of the Vastus Lateralis and Patellar Tendon

• Main Authors: Pablo Abián, Fernando Martínez, Fernando Jiménez, Javier Abián-Vicén
• Format: Article
• Language: English
• Published: MDPI AG 2020-12-01
• Series: International Journal of Environmental Research and Public Health
• Subjects: eccentric exercise; single-leg decline squat; patellar tendon; vastus lateralis
• Online Access: https://www.mdpi.com/1660-4601/17/24/9410
• ISSN: 1661-7827; 1660-4601

The purpose was to examine the effect of 6-week eccentric single-leg decline squat (SLDSe) training with two technical execution times (3 s or 6 s) on changes related to the structural properties of the vastus lateralis (VL) and patellar tendon (PT). Thirty-six physical active volunteers were randomly divided into three groups: control group (CG, <i>n</i> = 13, age = 20.8 ± 1.9 years, no intervention program), experimental group 1 (EG1, <i>n</i> = 11, age = 21.6 ± 2.5 years, execution time = 6 s) and experimental group 2 (EG2, <i>n</i> = 12, 21.1 ± 1.2 years, execution time = 3 s). Participants completed a 6-week SLDSe training program (80% of 1-RM) three days a week. The structural characteristics of the VL and the PT were measured with ultrasonography before and after 6-week SLDSe training and after 6 weeks of de-training. Our results indicate that EG1 increased ≈21.8% the thickness of the PT and EG2 increased ≈15.7% the thickness of the VL after the 6-week intervention program. EG1 and EG2 showed greater values (<i>p</i> < 0.05) of lean mass and lower values (<i>p</i> < 0.05) of fat percentage on the thigh after the intervention program. In conclusion, the SLDSe training carried out with the execution time of 6 s had greater effects on the structural and elastic properties of the PT, and the exercise with the execution time of 3 s caused greater structural adaptations in the VL musculature.