(62) MULTI-DIRECTIONAL ASSESSMENT OF ISOMETRIC NECK STRENGTH IN FEMALE HOCKEY PLAYERS

Female ice hockey players experience higher incidence of concussions than males despite prohibited intentional body contact. Neck strength seems to play a role in influencing the risk of concussions in female ice hockey players, who have lower neck strength levels than males. This finding suggests that female ice hockey players need to develop their overall neck strength as an avenue to minimize the risk of a concussion injury since players experience impact forces from various directions. Information regarding muscle neck strength for female ice hockey players, however, is limited, particularly in side flexion. PURPOSE: The purpose of this study was to examine isometric neck strength in competitive female hockey players in multiple directions including flexion, extension, and side flexion. METHODS: Twenty-five participants were recruited who were competitive female hockey players on the university team or in the senior division of a local women’s league (age = 22.1 ± 2.6 years; playing experience = 15.8 ± 2.7 years; body mass = 71.7 ± 10.9 kg; height = 165.3 ± 5.2 cm, neck length = 8.2 ± 0.9 cm, neck girth = 33.7 ± 17 cm). Isometric neck strength testing was completed using a modified Nautilus neck strengthening machine. Maximal isometric neck flexion, extension, and side flexion strength were measured using a load cell, which was attached to the arm of the Nautilus machine using a metal chain to hold the arm in a neutral neck position. After completing a warm-up, three trials were performed for each direction in random order, with two minutes rest provided between trials. The peak force measured for the three trials in each direction was used for the analysis. The relative force values were obtained by normalizing the absolute force to body weight. Repeated measures ANOVAs were used to examine the differences of the absolute and the relative peak isometric force among neck flexion, neck extension, and neck side flexion. Tukey’s post-hoc analysis was performed for pair mean comparisons. All analyses were performed with an alpha level set a priori at p ≤ 0.05. RESULTS: Mean ± SD peak isometric force values were: neck flexion = 71.6 ± 14.9 N; neck extension = 96.1 ± 25.2 N; neck side flexion = 78.5 ± 19.3 N. Significant differences were found in both absolute (p < 0.001) and relative (p < 0.001) peak isometric force across the three directions. Post-hoc analysis revealed that absolute neck extension force was significantly greater than both flexion and side flexion (p < 0.001) with no differences between flexion and side flexion (p = 0.075). Similarly, relative neck extension force was significantly greater than both flexion and side flexion (p = 0.001) with no differences between flexion and side flexion (p = 0.059). CONCLUSIONS: Female hockey players demonstrate greatest neck strength in extension with no differences between flexion and side flexion directions. PRACTICAL APPLICATION: Trainers and coaches should recognize the importance of incorporating neck strengthening exercises into the training programs of female hockey players, with a specific focus on strength development in the flexion and side flexion directions. Future research should continue to investigate the influence of neck strength as a factor for reducing the risk of concussions in female hockey players.

Acknowledgements: None