Isokinetic Neck Strength And Power Of South African Senior And Junior Rugby Players

Abstract

Neck injuries are a pertinent problem in all rugby-playing countries and other contact sports. Weak muscles increase the risk of injury, thus strengthening of the neck is an effective, but often neglected method of injury prevention. The comparison of isokinetic strength and power variables between the positional categories (props: −p, hookers: −h, locks: −lck, and loose forwards: −lse) of senior (S-) and junior (J-) rugby players revealed strength and power differences. PURPOSE To determine whether significant differences (p<0.05) exist between senior and junior rugby players for neck strength and power. METHODS Neck strength and power of 111 senior (23 ± 3 yrs) and 208 junior (17 ± 1 yrs) rugby players were assessed isokinetically at 30°·0.sec−1 through cervical flexion, extension, and lateral flexion left and right. Comparisons between the positional categories of senior and junior players were made using multi-factorial ANOVA. RESULTS All senior positional categories (SPG), except the Sh, performed significantly better than the junior positional categories (JPG) on the measure of peak torque flexion (PTF). The Slck achieved the largest mean PTF (44 ± 9 Nm), which was significantly larger than the Jp mean PTF (31 ± 13 Nm), which was the largest among the JPG. On the measure of peak torque extension (PTE), only the Sp (67 ± 14 Nm) performed significantly better than the JPG. All SPG, except for the Sh, proved to be significantly stronger than the JPG on the measures of peak torque lateral flexion to the right (PTR) and left (PTL). The Slck achieved the largest PTR (69 ± 15 Nm) and PTL (66 ± 13 Nm) means. These performances were significantly stronger than the Jp PTR (55 ± 12 Nm) and Jlck PTL (53 ± 12 Nm) means respectively, which were the best performances among the JPG on these variables. The SPG were significantly more powerful than the JPG during flexion (PowF), however no significant difference in PowF was observed between the Sh and Slck and the Jp. During extension power (PowE) the Sp (248 ± 71 W) performed significantly better than the JPG. Limited significant differences between the SPG and JPG were observed during measurement of lateral flexion right (PowR) and left (PowL) power. No significant differences existed among the SPG, neither were any significant differences observed among the JPG for the strength and power variables. CONCLUSION It appears that senior rugby players, specifically Sp, have undergone neck strength and power adaptations to meet the specific requirements of their positions. Certain JPG are significantly weaker than the SPG and have not undergone similar positional adaptations, possibly placing them at increased risk of injury.