Traditional and Band-Assisted Nordic Hamstring Training Improves Knee Flexor Strength and Hip Range of Motion

Abstract Purpose To compare the training effects of traditional (TRAD) and band‑assisted (NHE ASSIST ) Nordic Hamstring Exercise on knee flexor force‑length characteristics, NHE execution, and hip range of motion (ROM). Methods Forty-five male ( n = 24) and female ( n = 21) collegiate athletes were recruited from a variety of sports (soccer, basketball, Gaelic football, rugby, athletics, and netball) to partake in a twice-weekly 8-week TRAD or NHE ASSIST training programme; 30 participants completed the intervention with ≥ 80% adherence. Knee flexor force production capacity (eccentric and isometric [at various lengths]), NHE execution, and hip ROM were examined pre- and post-training. Soreness was self-reported up to 48 h post-training using a visual analogue scale. Results No significant ( P > 0.05) group × time interaction effects nor main effects of group were revealed for any metric. Main effects of time revealed significant increases in eccentric (17% ± 19%) and isometric force at longer muscle lengths (180° [full extension] and 150° knee flexion; 9%–12% ± 20%–22%), break point angle (10 ± 11°), impulse (139% ± 159%), and hip flexion ROM (5 ± 6°) in both groups after training; larger effect sizes occurred within NHE ASSIST compared to TRAD regarding force production capacity, break point angle, impulse, and hip flexion ROM. Conclusion Eight weeks of NHE improved knee flexor strength (particularly at longer muscle lengths), NHE execution, and hip flexion ROM. NHE ASSIST did not confer statistically different adaptations than TRAD; however, early‑phase soreness was transiently lower within NHE ASSIST . Larger, standardised, and mechanistically informed trials are warranted to determine whether assistance meaningfully augments adaptations.