The effect of high-intensity physical exertion on measures of cervical spine, vestibular/ocular-motor screening, and vestibulo-ocular reflex function in university level collision and combative sport athletes

Objectives: To examine how high-intensity physical exertion affects clinical measures of cervical spine (CSp), vestibular/ocular motor screen (VOMS), and vestibulo-ocular reflex (VOR) function.

Design: Case series.

Setting: Sports Medicine Centre.

Participants: A total of 37 athletes consented to participate (22 rugby, 15 wrestling; 9 men, 28 women; median age = 19 years [range 17-23 years]).

Main outcome measures: Outcome measures included tests of CSp (cervical flexor endurance, head perturbation test, cervical flexion rotation test and anterolateral strength), VOR (head thrust test and dynamic visual acuity [DVA]), and a quantified version of the VOMS. These metrics were assessed prior to and after completing the 30-15 Intermittent Fitness Test. Bland-Altman plots and Wilcoxon signed-rank tests were utilized to analyze the data using an alpha of p < 0.004.

Results: Cervical anterolateral strength (kg) was reduced post-exertion on the left (z = 3.87; p < 0.001), but not on the right between conditions (z = -1.49; p = 0.14). Athletes reported increased dizziness (z = -3.55; p = 0.004) and had reduced DVA following exertion (z = -2.78; p < 0.001). All other metrics were not significantly different following exertion (p > 0.011).

Conclusion: Reduced performance on DVA, decreased left-anterolateral strength, and increased dizziness occurred following high-intensity exertion in varsity collision and combative athletes, which has implications for sideline screening for sport-related concussion.