Effects of eccentric overload training on patellar tendon and vastus lateralis in three days of consecutive running

• Published in: The knee Vol. 24; no. 3; pp. 570 - 579
• Main Authors: Sanz-López, Fernando, Berzosa, César, Hita-Contreras, Fidel, Martínez-Amat, Antonio
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2017; Elsevier Limited
• Subjects: Collagen; Doppler; Doppler effect; Healthy Volunteers; Humans; Injuries; Knee; Male; Muscle; Muscles; Musculoskeletal system; Orthopedics; Overtraining; Patellar Ligament - diagnostic imaging; Patellar Ligament - physiology; Pennation angle; Physical Conditioning, Human - methods; Physiology; Quadriceps Muscle - diagnostic imaging; Quadriceps Muscle - physiology; Running; Running - physiology; Skin & tissue grafts; Strength training; Studies; Tendon tissue; Tendons; Ultrasonic imaging; Ultrasonography; Ultrasound; Young Adult; Tendon tissue; Pennation angle; Muscle; Ultrasound; Doppler
• ISSN: 0968-0160; 1873-5800
• DOI: 10.1016/j.knee.2017.03.002

Abstract Background The analysis of structural changes in patellar tendon and muscle of healthy subjects in response to mechanical loads provides useful insight into the mechanism underlying overuse injuries. Methods We examined the temporal sequence of changes in structures in response to eccentric overload and to three consecutive running days. Twenty healthy subjects were recruited and divided into two groups. One group (ECC) performed eccentric overload squat training (six weeks). After such training, the ECC group performed three running sessions on consecutive days, as did the control group (CONT). The structure of their patellar tendons and vastus lateralis muscles were quantified using ultrasound and Doppler imaging. Images were obtained before and after eccentric training for the ECC group and on every day of running performance for both groups. Results After eccentric training, the ECC group experienced an increase in cross-sectional area (CSA) of patellar tendon ( P = 0.012). After every day of running, the ECC group experienced a decrease in CSA ( P = 0.027). In the CONT group, after 1 day of running a significant increase was observed in anteroposterior width of their patellar tendon ( P = 0.028), as well as a decrease in pennation angle of vastus lateralis muscle ( P = 0.028) within 3 days of running sessions. Conclusions Eccentric overload training brought about changes in the patellar tendon consistent with an improvement in the quality of the tissue. The ECC group in our study showed a more normalised pattern than the CONT group in the running performance, in agreement with previous research. Level of evidence Level 3, controlled trial.