ALTERATIONS IN POSTURAL CONTROL FOLLOWING AN ACUTE BOUT OF SOCCER HEADING

Abstract

This study sought to determine if an acute bout of soccer heading adversely altered postural control and pronounced self-reported symptoms of cerebral concussion. Sixteen collegiate soccer players were randomly assigned to one of two groups: control (CG) or experimental (EG). Participants either simulated or performed 10 headers in 10 min at a ball velocity 11.2 m/s. A concussion signs and symptoms checklist was completed and postural control was assessed on four separate occasions: prior to heading (hr 0), hr 1, hr 24, and hr 48 post heading. The postural control parameters were the root mean square (RMS) of the center of mass (COM) and approximate entropy (ApEN) of the center of pressure (COP). The results indicated that there were no significant differences between the CG and EG in the sum of self-reported concussion signs and symptoms; however, there were significant alterations in postural control, occurring primarily at 24 hrs following heading. Within the EG only there were significant differences across time for anterior-posterior (AP) COM RMS for conditions 3 (i.e., rotating virtual environment [VE] and stable support surface) and 4 (i.e., rotating VE and unstable support surface). Also, medial-lateral (ML) COM RMS values were significantly higher for the EG when compared to the CG at hr 24. The EG had significantly lower COP ApEn values in both the AP and ML directions when compared to the CG at hr 24. Condition 4 was found to induce significantly greater postural control deficits when compared to the other conditions in the ML COM RMS and AP COP ApEn. These findings indicate that an acute bout of heading, even at the low velocities presented in this experiment, result in quantifiable alterations in postural control that are detectable 24 hours post heading and dissipate within an additional 24 hours. The significant findings are contrary to the acute heading literature and may be due to the postural control assessment that incorporated robust discordant environmental conditions. Further research on the clinical usefulness of the assessment as well as long-term accumulation effects of heading is warranted.