Effects of assisted Nordic hamstring exercise on strength, range of motion, muscle soreness and perceived exertion: a pilot study

Description

Introduction
While the Nordic Hamstring Exercise (NHE) is used to increase hamstring eccentric strength and range of motion (ROM) to reduce hamstring strain incidence [1], poor adherence has been reported due to high exercise intensity and perceived muscle soreness [2]. However, the use of elastic resistance bands during the NHE may reduce loading to alleviate symptoms of muscle soreness. Therefore, the aim of this study was to examine the efficacy of assisted NHE to improve hamstring strength and ROM, whilst assessing perceptual measures (muscle soreness and exertion [RPE]).

Methods
Twenty-nine university team sport athletes ([mean±SD] 21.1±2.1y) took part in an 8-week training programme twice per week, progressing from two sets of three NHE repetitions in week 1 to four sets of four in week 8. Athletes were stratified based upon NHE strength and body mass, and then assigned to a group that performed NHE (UNASSIST n=12) or NHE assisted with an elastic resistance band (ASSIST n=17). RPE was reported immediately after performing NHE with muscle soreness reported at 24 and 48 hr post-training. Hamstring strength (NHE peak force and isometric force measured at 0, 30, and 60° knee flexion [0°=full extension]) and ROM were measured pre- and post-intervention. Twenty-five athletes (UNASSIST n=10; ASSIST n=15) were included in the analyses of perceptual measures during the initial four weeks, however due to attrition unrelated to the programme, 13 athletes (UNASSIST n=6; ASSIST n=7) were included in post-intervention muscle function assessments.

Results
During the initial week, UNASSIST reported significantly (P
Conclusion
These preliminary data indicate that assisted NHE can elicit improvements in hamstring muscle strength and ROM, despite a lower exercise intensity. The reduced intensity may allow unaccustomed individuals to be eased into a NHE training programme via reduced perceptions of muscle soreness, whilst still benefiting from positive adaptations. However, further research using a larger sample size is needed to confirm these findings.

References
1.Van der Horst et al. (2015). Am J Sports Med. 43:1316-1323.
2.Ripley et al. (2021). Int J Environ Res Public Health. 18:11260.

Period	7 Jul 2023
Event title	28th Annual Congress of the European College of Sport Science (ECSS)
Event type	Conference
Location	Paris, FranceShow on map
Degree of Recognition	International