training lasting ≤40 min produced better T-test results (SMD: 1.10; 95% CI: 1.95, -0.25; p = 0.01; I² = 55%). Longer sessions showed no significant advantage. For training background (Figure 7), experienced participants benefited more from sand training (SMD: 1.44; 95% CI: 2.34, -0.55; p = 0.002; I² = 72%). No benefit was seen in participants without training experience (SMD: 0.09; 95% CI: 0.55, 0.37; p = 0.71; I2 = 0%).The minus signs (-) before some of the data points were omitted, resulting in an incorrect reversal of the positive and negative values during the proofing stage. A correction has been made to the section Subgroup analysis of COD ability:"For intervention duration (Figure 4), sand training lasting over ＞6 weeks showed better T-test results than other surfaces (SMD: -1.19; 95% CI: -2.05, -0.07; p = 0.007; I² = 79%). No difference was observed for programs lasting 6 weeks or less (SMD: 0.05; 95% CI: -0.63, 0.74; p = 0.88; I² = 20%). For training frequency (Figure 5), sand training with three sessions per week improved T-test performance more than other surfaces (SMD: -1.15; 95% CI: -2.02, -0.28; p = 0.01; I² = 81%). No benefit was found with two weekly sessions (SMD: 0.12; 95% CI: -0.71, 0.95; p = 0.77; I² = 23%). For session duration (Figure 6), sand training lasting ≤ 40 min produced better T-test results (SMD: -1.10; 95% CI: -1.95, -0.25; p = 0.01; I²= 55%). Longer sessions showed no significant advantage. For training background (Figure 7), experienced participants benefited more from sand training (SMD: -1.44; 95% CI: -2.34, -0.55; p = 0.002; I² = 72%). No benefit was seen in participants without training experience (SMD: -0.09; 95% CI: -0.55, 0.37; p = 0.71; I² = 0%)." The original version of this article has been updated.Regarding intervention duration (Figure 8), sand training lasting > 6 weeks (SMD: 1.42; 95% CI: 0.00, 2.83; p = 0.05; I² = 85%) and ≤6 weeks (SMD: 0.61, 95% CI: 0.04, 1.18; p = 0.04; I²= 48%) all showed better SLJ results than other surface. However, longer training periods yield superior improvements. For training frequency (Figure 9), sand training performed ≥3 times per week improved SLJ performance more than other surfaces (SMD: 1.04; 95% CI: 0.34, 1.74; p = 0.003; I² = 72%). No benefit was found with fewer than 3 weekly sessions. For training background (Figure 10), participants without training experience had better SLJ results with sand training (SMD: 0.68; 95% CI: 0.21, 1.15; p = 0.005; I²= 0%). No significant difference was seen in experienced participants (SMD: 0.96; 95% CI: 0.11, 2.03; p = 0.08; I²= 82%).The minus signs (-) before some of the data points were omitted, resulting in an incorrect reversal of the positive and negative values during the proofing stage. A correction has been made to the section Subgroup analysis of SLJ ability:"[Regarding intervention duration (Figure 8), sand training lasting ＞ 6 weeks (SMD: 1.42; 95% CI: 0.00, 2.83; p = 0.05; I² = 85%) and ≤ 6 weeks (SMD: 0.61, 95% CI: 0.04, 1.18; p = 0.04; I²= 48%) all showed better SLJ results than other surface. However, longer training periods yield superior improvements. For training frequency (Figure 9), sand training performed ≥ 3 times per week improved SLJ performance more than other surfaces (SMD: 1.04; 95% CI: 0.34, 1.74; p = 0.003; I² = 72%). No benefit was found with fewer than 3 weekly sessions. For training background (Figure 10), participants without training experience had better SLJ results with sand training (SMD: 0.68; 95% CI: 0.21, 1.15; p = 0.005; I² = 0%).
Wang et al. (Thu,) studied this question.