ABSTRACT
Background: Dynamic postural control (DPC) describes an individual's ability to maintain balance within their base of support in both anticipatory and reactive balance situations and has been measured using center of pressure (COP) velocity. Common standardized DPC assessments for active adults include the modified Star Excursion Balance Test (MSEBT) and the Y-Balance Test (YBT). Hypothesis/Purpose: The purpose of this study was to explore DPC during performance of the MSEBT, the YBT, and a modified version of the YBT, the MYBT. It was hypothesized that feedback from the YBT/MYBT reach indicator would enhance DPC. Study Design: Cross-sectional study. Methods: Twenty-one participants (9 females, 12 males, mean age 24.5±1.2 years) performed three trials in each direction (anterior-AN, posteromedial-PM, and posterolateral-PL) on each balance test during one session. The YBT frame was placed atop a force plate for all testing. Frontal and sagittal plane COP velocities (COPx and COPy, respectively) were recorded throughout each trial and resultant COP (COPr) velocities were calculated. Results: Significant main effects were present for test (F=4.485, p\<0.001) and reach direction (F=61.594, p\<0.001). Post hoc analyses for test indicated significant differences in COPy between YBT and MSEBT (p=0.034) and between MYBT and MSEBT (p\<0.001), as well as significant differences in COPr between MYBT and MSEBT (p=0.002). Post hoc analyses for reach direction revealed significant differences in COPx between AN and both PM (p\<0.001) and PL (p\<0.001) directions, in COPy between AN and PM (p\<0.001) and PL (p\<0.001) directions, and COPr between AN and PL (p=0.043) directions only. Conclusion: External proprioceptive feedback from the reach indicator improved DPC during the YBT and MYBT when compared to the MSEBT. Sagittal plane COP velocities were reduced when external proprioceptive feedback from the reach indicator was present, while frontal plane COP velocities were not affected in this group of participants. Level of Evidence: 2b.
ABSTRACT
ABSTRACT: Choice, EE, Tufano, JJ, Jagger, KL, and Cochrane-Snyman, KC. Match-play external load and internal load in NCAA Division II women's soccer. J Strength Cond Res 37(12): e633-e639, 2023-The purpose of this study was to describe average match-play demands for NCAA DII women's soccer, including positional and time-specific differences, and relationships between variables. External load was assessed using total distance, relative distance, sprint distance, number of power plays, peak speed, and Player Load. Internal load was assessed using session rating of perceived exertion (sRPE). Mixed factor analysis of variance was used to assess time by position (midfielder, forward, or defender) for dependent measures. Correlations were assessed between separate pair groups. Average match-play demands included 9,463 ± 2,591 m total distance, 172 ± 48 m·min -1 relative distance, 531 ± 301 m sprint distance, peak speeds of 26 ± 1.6 kph, 46.71 ± 21.75 power plays, and 457.84 ± 121.78 AU Player Load. Significant ( p < 0.05) positional differences were found for total distance, Player Load, match load, and peak speed. Significant, moderate correlations were found between relative distance and match load, and sRPE and total distance, Player Load, and power plays (all p < 0.001). Results indicate there are positional differences within a women's DII soccer team, with midfielders accumulating the longest distances (10,509 ± 2,913 m) and greatest Player Load (527.79 ± 130.5 AU) and match load (576 ± 343 AU), forwards running the fastest peak speeds (26.8 ± 1.5 kph), and defenders maintaining most consistent performance. Match-play external and internal load data should be monitored by player position and half for DII women's soccer.