Table 3 Correlations of Y Balance Test-Upper Quarter side differences and performance with serve velocity by level of training experience
Outcome | Flat serve velocity [km/h] | Slice serve velocity [km/h] | ||||||
|---|---|---|---|---|---|---|---|---|
All players (N = 42) | YoT: <2 (n = 14) | YoT: 2–5 (n = 17) | YoT: 6–8 (n = 11) | All players (N = 42) | YoT: <2 (n = 14) | YoT: 2–5 (n = 17) | YoT: 6–8 (n = 11) | |
YBT-UQ: side difference | ||||||||
LSI for the medial reach [% AL] | 0.14 | − 0.26 | 0.39 | 0.43 | 0.04 | − 0.39 | 0.30 | 0.31 |
LSI for the inferolateral reach [% AL] | − 0.15 | − 0.48 | − 0.15 | 0.22 | − 0.05 | − 0.23 | − 0.20 | − 0.06 |
LSI for the superolateral reach [% AL] | 0.08 | 0.12 | − 0.15 | 0.19 | 0.28 | 0.31 | 0.01 | 0.42 |
LSI for the composite score [% AL] | − 0.05 | − 0.32 | − 0.09 | 0.20 | 0.12 | − 0.14 | 0.06 | 0.07 |
YBT-UQ: performance | ||||||||
SA: medial reach [% AL] | 0.38* | 0.48 | 0.32 | 0.11 | 0.57*** | 0.57* | 0.54* | 0.35 |
SA: inferolateral reach [% AL] | − 0.01 | 0.18 | − 0.13 | − 0.24 | 0.14 | 0.18 | 0.07 | 0.07 |
SA: superolateral reach [% AL] | 0.10 | 0.43 | − 0.06 | − 0.21 | 0.12 | 0.28 | − 0.05 | 0.04 |
SA: composite score [% AL] | 0.20 | 0.46 | 0.05 | − 0.13 | 0.36* | 0.43 | 0.29 | 0.16 |
NSA: medial reach [% AL] | 0.41** | 0.65* | 0.26 | 0.20 | 0.55*** | 0.53* | 0.47 | 0.49 |
NSA: inferolateral reach [% AL] | − 0.10 | − 0.09 | − 0.10 | − 0.33 | − 0.02 | − 0.03 | − 0.12 | − 0.15 |
NSA: superolateral reach [% AL] | 0.10 | 0.35 | − 0.07 | 0.03 | 0.07 | 0.26 | − 0.14 | 0.19 |
NSA: composite score [% AL] | 0.17 | 0.39 | 0.02 | − 0.05 | 0.26 | 0.33 | 0.05 | 0.20 |