Mixed
Both Nordic hamstring exercises (NHE) and hip extension exercises (HE) significantly increase biceps femoris long head (BFLH) fascicle length, with no significant difference between the two methods, thereby potentially reducing hamstring injury risk.
Perform the Nordic Hamstring Exercise (NHE) or Hip Extension (HE) twice weekly for 10 weeks to significantly increase hamstring fascicle length, which is linked to reduced injury risk. Start with bodyweight for NHE and progress to adding weight as you get stronger. For HE, start at 60-70% of your one-rep max and increase load progressively. Both exercises are effective for lengthening the biceps femoris long head, a key factor in preventing strains.
NHE and HE training both stimulate significant increases in BFLH fascicle length; however, HE training may be more effective for promoting hypertrophy in the BFLH.
Why this rating
Randomized controlled trial with 30 participants, clear intervention, and objective imaging (MRI/Ultrasound).
Source
Impact of the Nordic hamstring and hip extension exercises on hamstring architecture and morphology: implications for injury prevention
Matthew N. Bourne et al. · British Journal of Sports Medicine · 2016
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