Table 1. Mean ± standard deviation (SD) and statistical results obtained in the present study.
Variables Start
segment
Turn
segment
Correlation
coefficient
T-test
Difference
ANOVA
Start
(vs. T0-15)
Turn
(vs. T25-35)
Main effect
(Segments)
Main effect
(Events)
Interaction
Lap time (s) 11.51 ± 0.43 13.71 ± 0.59 0.93 0.90 n.a. n.a.
T0-15 and T25-35 (s) 6.24 ± 0.25 5.35 ± 0.25 n.a. n.a. n.a. n.a.
UW-vxmean (m·s-1) 2.26 ± 0.11 1.98 ± 0.08 -0.70# -0.95 0.28 ± 0.92 n.a.
UW Time (s) 3.23 ± 0.61 3.18 ± 0.81 -0.51 -0.41 0.46 ± 0.61 n.a.
UW Distance (m) 7.26 ± 1.42 6.29 ± 1.68 -0.64 -0.57 0.97 ± 1.12# n.a.
Kick frequency (Hz) 2.52 ± 0.23 2.16 ± 0.19 -0.16 -0.46 0.36 ± 1.55 n.a.
Kick count (times) 7.00 ± 1.56 5.71 ± 2.09 -0.70# -0.55 1.29 ± 1.49# n.a.
Deckick (m·s-2) -0.51 ± 0.23 -0.36 ± 0.27 0.33 0.43 -0.16 ± 0.21* n.a.
Glide time (s) 0.40 ± 0.13 0.59 ± 0.27 0.56 0.33 -0.20 ± 0.20# n.a.
Initial-vxhead (m·s-1) 4.60 ± 0.33 3.04 ± 0.16 0.03 -0.48 n.a. F = 476.71
η2P = 0.97
F = 438.07
η2P = 0.97
F = 137.95
η2P = 0.91
First-vxhead (m·s-1) 2.70 ± 0.27 2.13 ± 0.21 -0.86 -0.59 n.a.
Last-vxhead (m·s-1) 1.81 ± 0.15 1.70 ± 0.11 -0.55 -0.51 n.a.
Initial-vyhead (m·s-1) -1.51 ± 0.52 -0.39 ± 0.22 0.57 0.66 n.a. F = 121.08
η2P = 0.90
F = 49.47
η2P = 0.79
F = 70.67
η2P = 0.85
First-vyhead (m·s-1) 0.11 ± 0.24 0.002 ± 0.16 0.69# 0.39 n.a.
Last-vyhead (m·s-1) 0.34 ± 0.10 0.25 ± 0.10 -0.50 -0.65 n.a.
Initial-BA (˚) -14.63 ± 8.42 -6.93 ± 5.58 0.48 0.69# n.a. F = 60.26
η2P = 0.82
F = 1.12
η2P = 0.08
F = 14.71
η2P = 0.53
First-BA (˚) 7.57 ± 7.02 3.44 ± 6.78 0.70# 0.46 n.a.
Last-BA (˚) 12.62 ± 5.34 11.43 ± 6.09 -0.29 -0.15 n.a.
T0-15, 0-15 m time; T25-35, 25-35 m time; UW, underwater; vxmean, forward velocity; Deckick, the mean deceleration from the first to the last kick; Initial-vxhead, the forward head velocity at the feet entry or push-off; First-vxhead, the mean forward velocity during the first kick; Last-vxhead, the mean forward velocity during the last kick; Initial-vyhead, the upward head velocity at the feet entry or push-off; First-vyhead, the mean upward velocity during the first kick; Last-vyhead, the mean upward velocity during the last kick; Initial-BA, the angle of the upper body at the feet entry or push-off; First-BA, the mean angle of the upper body during the first kick; Last-BA, the mean angle of the upper body during the last kick; η2P, Partial eta squared.
*, p < 0.05;
#, p < 0.01;
†, p < 0.001; n.a., not applicable