Background The Nordic hamstring exercise (NHE) is commonly implemented to selectively improve eccentric knee-flexor strength. However, the standard version of the exercise (leveled shanks, extended hip joint) is too strenuous for most individuals, whose muscle activity rapidly decreases at extended knee angles. Hitherto, a gradual approach to the exercise has been missing. In this exploratory case study, we investigated elite performance to introduce a stepwise progression to the NHE. Objective To determine the extent to which exercise modifications (shank inclination, additional load, hip flexion) altered NHE mechanics. Data Collection and Analysis One male long jumper (age = 33 years, height = 171 cm, mass = 69 kg) with high-level expertise in the NHE performed 20 exercise variations. The corresponding kinematics, kinetics, and electromyographic activity of the biceps femoris long head (BFlh) and semitendinosus (ST) muscles were evaluated. Results Exercise variations demonstrated gradually increased peak moments from 69% (zigzag pose) to 154% (inclined bent single-legged version) versus a standard NHE. Shank inclination and additional load elicited small to moderate effects on peak moments, BFlh, and ST (0.24 = d = 0.72), whereas hip flexion largely affected all tested variables (2.80 = d = 6.66), especially muscle activity (BFlh = -63%; ST = -55% of maximal voluntary isometric contraction). Commentary These insights will help practitioners and scientists design multifaceted stepwise NHE progressions by creating differentiated stimuli that best match the strength capacities of individuals and address their specific needs. Key Points - A regression and progression of the standard version of the Nordic hamstring exercise (NHE) is justified to adapt the stimuli to the specific needs and capacities of each individual in order to guarantee high-level hamstring activation and strength capacities in extended knee angles. - A 6-level stepwise progression model is introduced, which consists of 15 exercises that demonstrated gradually increased peak moments from 69% to 154% versus a standard NHE. - Five standardized cutoff exercises enable an uncomplicated classification of each individual by performance level. - Three exercises favored greater biceps femoris long head activation, which is vital for effective injury prevention, rehabilitation, and performance enhancement. - Hip flexion largely affected peak moments and biceps femoris long head and semitendinosus activity, whereas shank inclination and additional load elicited small to moderate effects.
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