The aim of this controlled laboratory study was to examine the effectiveness of a neck strengthening program on the isometric neck strength profile of male rugby union players. Fifteen professional and 10 semiprofessional rugby union players participated in the study. The 15 professional players completed a 5-week neck strengthening intervention, which was performed twice per week, whereas the 10 semiprofessional players acted as the control group. Isometric strength of the neck musculature was tested using a hand-held dynamometer, for flexion (F), extension (E), left-side flexion (LSF), and right-side flexion (RSF). Preintervention and postintervention evaluations were conducted. No significant between-group differences in isometric neck strength were noted preintervention. A significant main effect for time was observed (P < 0.05), whereby the intervention group increased isometric neck strength in all planes after the 5-week intervention (F preintervention = 334.45 ± 39.31 N vs F postintervention 396.05 ± 75.55 N; E preintervention = 606.19 ± 97.34 vs E postintervention = 733.88 ± 127.16 N; LSF preintervention = 555.56 ± 88.34 N vs LSF postintervention = 657.14 ± 122.99 N; RSF preintervention = 570.00 ± 106.53 N vs RSF after intervention = 668.00 ± 142.18 N). No significant improvement in neck strength was seen for control group participants.

The results of this study suggest that a 5-week neck strengthening program improves isometric neck strength in rugby union players, which may have implications for injury prevention, screening and rehabilitation. The strengthening program outlined in the study could facilitate rehabilitation specialists in the development of neck injury prevention, screening, and rehabilitation protocols.