Impact of the Nordic hamstring and hip extension exercises on hamstring architecture and morphology: implications for injury prevention

• Published in: British journal of sports medicine 2017-03, Vol.51 (5), p.469-477
• Main Authors: Bourne, Matthew N, Duhig, Steven J, Timmins, Ryan G, Williams, Morgan D, Opar, David A, Al Najjar, Aiman, Kerr, Graham K, Shield, Anthony J
• Format: Article
• Language: English
• Subjects: Adult; Athletic Injuries - prevention & control; Australian football; Exercise; Hamstring Muscles - anatomy & histology; Hamstring Muscles - diagnostic imaging; Hamstring Muscles - physiology; Humans; Injury prevention; Intervention; Knee; Longitudinal Studies; Male; Morphology; Muscle Strength - physiology; Muscle Stretching Exercises; Physical fitness; Professional soccer; Questionnaires; Research ethics; Soccer; Strength training; Ultrasonography; Young Adult
• ISSN: 0306-3674; 1473-0480
• DOI: 10.1136/bjsports-2016-096130

BackgroundThe architectural and morphological adaptations of the hamstrings in response to training with different exercises have not been explored.PurposeTo evaluate changes in biceps femoris long head (BFLH) fascicle length and hamstring muscle size following 10-weeks of Nordic hamstring exercise (NHE) or hip extension (HE) training.Methods30 recreationally active male athletes (age, 22.0±3.6 years; height, 180.4±7 cm; weight, 80.8±11.1 kg) were allocated to 1 of 3 groups: (1) HE training (n=10), NHE training (n=10), or no training (control, CON) (n=10). BFLH fascicle length was assessed before, during (Week 5) and after the intervention with a two-dimensional ultrasound. Hamstring muscle size was determined before and after training via MRI.ResultsCompared with baseline, BFLH fascicles were lengthened in the NHE and HE groups at mid-training (d=1.12–1.39, p