The relationship of a modified agility T-Test with stretch-shortening cycle and straight sprint acceleration.

Abstract

There is an inconsistency in the understanding of stretch-shortening cycle and acceleration characteristics in the change of direction speed component of agility. The modified agility t-test is a contemporary protocol recently established as a reliable and quantifiable measure of change of direction speed and its components. The purpose of the present study was to explore the relationship of the stretch-shortening cycle and straight sprint acceleration components of agility using the modified agility t-test.

After receiving ethics approval, twenty-eight male team-sport athletes (Mean ± SD; Age: 20.6 ± 0.8 years; Stature: 179.8 ± 6.3 cm; Body Mass: 82.0 ± 8.7 kg) attended two sessions. In the first session a squat jump (SJ), a countermovement jump (CMJ), and a rebound jump (RBJ) were recorded using a timing mat system, where flight time, jump height, contact time and reactive strength index (jump height/contact time) were computed. The second session included a 20 m straight sprint (20mSS), with a 10 m split, and a modified agility t-test (MAT) which were both measured using timing gates. The best score from three trials were used for further analysis.

Significant correlation coefficients (r) were found between the MAT and SJ, CMJ, RSI and 20mSS (r = -0.52, r = -0.44, and r = -0.58, r = 0.38, p < 0.05, respectively). However, even though these relationships were significant with additional negligible standard error of estimates (all ≤ 5.2%), in all instances there was a low amount of common variance (all < 33%).

Results demonstrate that acceleration is not related to CODS (MAT). Conversely, strength (SJ), slow SSC (CMJ) and fast SSC (RBJ) do share some relationship to CODS (MAT) performance. This suggests that by improving jump height while reducing contact time (i.e. through plyometric and sprint training), could improve CODS performance if appropriately implemented by a coach.