The effect of the Nordic Hamstring Exercise vs. the Romanian Deadlift on neuromuscular performance in elite male youth footballers

The purpose of this study was to investigate the effectiveness of eccentric hamstring training through use of the Nordic Hamstring Exercise (NHE) on four neuromuscular tests: acceleration, maximal running speed, countermovement jump (CMJ) and reactive strength index (RSI) in comparison to another commonly used hamstring exercise, the Romanian Deadlift (RDL). Fifty-two elite male youth football players were placed into two separate training groups, the intervention group which contained the NHE and the control group which contained the Romanian Deadlift (RDL). Participants were matched in terms of their percentage maturation producing two sub groups called lower maturation (93-96%) and higher maturation (97-100%). Both training groups participated in a periodised programme over eight weeks and were tested pre- and post- experiment for each neuromuscular test. Significant main effects on time (pre and post) were found for CMJ (p > 0.0005) and hamstring strength (p > 0.0005) and significant main effects on groups were found for acceleration (p = 0.001), maximal running speed (p > 0.0005), CMJ (p = 0.014) and RSI (p = 0.029). The results found that no significant interaction was found between the groups and time (pre and post) for acceleration (p = 0.555), maximal running speed (p = 0.909), CMJ (p = 0.561), RSI (p = 0.310) or hamstring strength (p = 0.528). The NHE or RDL exercise showed no difference between each other on neuromuscular performance however, the groups with the higher maturity status showed superior physical differences in comparison to the lower maturation groups for the different neuromuscular tests demonstrating that the level of physical maturity may be factor in differences between neuromuscular performance rather than hamstring strength.