Comparison of Different Functional Tests for Leg Power and Normative Bilateral Asymmetry Index in Healthy Collegiate Athletes

Correlations Between Preseason Functional Test Scores and Game Performance in Female Collegiate Volleyball Players

Background

Functional tests (FT) are assessment tools that attempt to evaluate balance, flexibility, strength, power, speed, or agility through performance of gross motor skills. FT are frequently administered by coaches or sports medicine professionals to evaluate athletic ability, to predict performance, to identify athletes at risk for injury, or to evaluate an athlete's ability to return to sport after injury. Functional tests which can provide accurate or predictive information regarding athletic ability would be advantageous to coaching staffs or medical professionals.

Purpose

The primary purpose of this study was to identify correlations between preseason FT scores and in-season game statistics in a cohort of female collegiate level volleyball (VB) players. A secondary purpose was to present FT descriptive data for this cohort based on level of competition, player position, and starter status.

Study Design

prospective cohort; correlational.

Methods

One hundred and thirty-one female collegiate VB players representing three levels of competition completed four FT [standing long jump (SLJ), single-leg hop (SLH), lower extremity functional test (LEFT), and the Y-Balance Test - Lower Quarter (YBT-LQ)] at the start of the preseason. Player statistics were collected from team records at the completion of the season.

Results

Starters performed significantly better on all tests. There were moderate negative correlations between LEFT scores and game statistics for liberos, defensive specialists, and outside hitters. There were moderate positive correlations between YBT-LQ composite scores and game statistics for liberos, defensive specialists, hitters, and middle blockers. There were also low to moderate level positive correlations between SLJ and SLH scores and game performance for outside hitters. There were low to moderate level positive correlations between SLH scores and game performance for middle blockers and opposite side hitters.

Conclusions

The results of this study indicate that there are low to moderate correlations between some preseason functional test scores and some game statistics. The SLJ, SLH, LEFT, and YBT-LQ tests may help coaches with talent identification and/or may influence training strategies.

Level of Evidence

3.

A Compound Hop Index for Assessing Soccer Players' Performance

Athletes regularly have to pass a series of tests, among which one of the most frequently used functional performance measures are single-leg hop tests. As the collected individual results of tests constitute a large amount of data, strategies to decrease the amount of data without reducing the number of performed tests are being searched for. Therefore, the study aimed to present an effective method to reduce the hop-test battery data to a single score, namely, the Compound Hop Index (CHI) in the example of a soccer team. A male, first-league soccer team performed a battery of commonly used single-leg hop tests, including single hop and triple hop for distance tests and the six-meter timed hop test. Gathered data, including Limb Symmetry Indexes of the three tests, normalized to body height for the single- and triple-hop-tests distance separately for right and left legs, and the time of the six-meter timed hop test separately for right and left legs were standardized to z-scores. Consecutively, the z-scores were averaged and formed CHI. The developed CHI represents a novel score derived from the average of z-scores that significantly reduces, clarifies, and organizes the hop performance-measures data.