Effects of Surface Compliance and Instrument on Collegiate Marching Artist Postural Control
“Background
Collegiate marching artists perform drill at a high intensity which requires both playing an instrument while simultaneously maintaining postural control. However, how the external load of instrument and surface influences postural control performance is not well understood. The purpose of this study was to determine the influence of holding an instrument and surface on static postural control performance during both double-legged (DL) and single-legged (SL) stances.
Methods
Twenty-three marching artists (13 M, 10 F, 20.26 ± 1.71 yrs, 174.99 ± 1.74 cm, 77.44 ± 18.41 kg) from a university marching band participated in this study. Static postural control performance was assessed on a tri-axial force plate for 20 seconds under four conditions for DL and SL stances: 1) firm surface with an instrument (INST), 2) firm surface without INST, 3) foam surface with an INST, and 4) foam surface without an INST. Analyses were completed for double-leg and single-leg stances independently. A 2×2 repeated measures ANOVA was performed for each outcome variable. Alpha level was set a priori at p≤0.05.
Results
Total, anterior-posterior (AP), and medial-lateral (ML) center-of-pressure (CoP) excursion and 95% sway area were analyzed. A surface main effect was observed for all outcome variables during DL stance (p<0.01). There was a surface main effect for total and ML CoP excursion for single-leg conditions (p<0.01). Surface condition did not have a significant main effect on AP CoP excursion and sway area. Pairwise comparisons demonstrated total CoP excursion was significantly lower on firm surface compared to foam surface in all SL and DL conditions (p<0.01). No significant instrument main effect or instrument by condition interactions were observed for either DL or SL stances.
Conclusion
CoP excursion was significantly different in marching artists in all DL conditions and two SL conditions (ML and total CoP excursion SL stance) based on surface compliance. No significant difference was shown in CoP excursion based on the presence of an instrument for any condition. These results suggest marching artists CoP excursion is significantly changed based on the compliance of the playing surface (turf, grass, etc.) that could potentially increase risk of poor postural mechanics.”