## 3 Results
### Acute Effects of Static Stretching  
This section reviews the acute (a single session of intervention) effects of static stretching on neuromuscular properties from 31 studies [32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 50; 51; 52; 53; 54; 55; 56; 57; 58; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68; 69]. The total number of participants across the 31 studies was 550 (median: 16; range: 10-30). Of the 31 studies, six studies assessed neural responses (\(n=106\)) [52; 53; 54; 55; 56; 57], and 25 studies investigated muscular responses [32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 58; 59; 60; 61; 62; 63; 64; 65; 66; 67; 68; 69]. The main findings are summarized in Table 1.  
Joint behavior responses were reported in 25 studies [32; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 56; 57; 58; 59; 60; 61; 62; 63; 65; 66; 67; 68; 69]. ROM was reported in 24 studies [32; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 56; 57; 58; 59; 60; 61; 62; 63; 65; 66; 67; 68; 69], and all the studies showed a significant increase. Of these studies, one study examined two stretching methods (i.e., constant angle and constant torque) [67], two studies examined two [66] or three [43] different intensities, and one study examined three different rest intervals [41], and the raw values from one study were not available [54]. This led to the attainment of a total of 29 data points from 23 studies. A meta-analysis revealed a significant overall large effect with moderate heterogeneity (\(d=0.91\); 95% CI = 0.71 to 1.10; \(p<0.001\); \(I^{2}=53\%\); Figure 2A). PRT\({}_{\rm max}\) was reported in five studies [37; 41; 58; 59; 60; 61], showing a significant increase in all but one study [37]. Of these five studies, one study examined three different rest intervals [41], and the raw values from two studies were not available [59; 60], which led to a total of five data points being available. A meta-analysis revealed a significant overall moderate to large effect with low heterogeneity (\(d=0.78\); 95% CI = 0.41 to 1.16; \(p<0.001\); \(I^{2}=18\%\); Figure 2C). MVIT was reported in 12 studies [32; 44; 54; 56; 57; 59; 60; 62; 65; 67; 69], and nine studies showed a significant decrease [44; 54; 56; 57; 59; 60; 62; 65; 69], whereas three studies did not show a significant change [32; 61; 67]. Of these studies, one study examined two stretching methods [67], one study examined two protocols [54], and the raw values from one study were not available [60], leading to a total of 13 data points from eleven studies. A meta-analysis revealed a significant small to moderate effect with moderate to high heterogeneity (\(d=-0.48\); 95% CI = \(-0.82\) to \(-0.15\); \(p=0.01\); \(I^{2}=68\%\); Figure 2D). MTU stiffness was reported in 11 studies [32; 58; 59; 60; 61; 62; 63; 65; 66; 67; 68], and 10 studies showed a significant decrease [32; 58; 59; 60; 62; 65; 63; 65; 67; 68], while one study did not show a significant change [66]. Of these studies, one study examined two stretching methods [67], one study examined two different intensities [66], and the raw values from one study were not available [58], leading to a total of 12 data points from 10 studies. A meta-analysis revealed a significant low to moderate effect with no heterogeneity (\(d=-0.38\); 95% CI = \(-0.15\); \(p=0.01\); \(I^{2}=68\%\); Figure 2D). MTU stiffness was reported in 11 studies [32; 58; 59; 60; 61; 62; 63; 65; 66; 67; 68], and 10 studies showed a significant decrease [32; 58; 59; 60; 63; 65; 67; 68], while one study did not show a significant change [66]. Of these studies, one study examined two stretching methods [67], one study examined two different intensities [66], and the raw values from one study were not available [58], leading to a total of 12 data points from 10 studies. A meta-analysis revealed a significant low to moderate effect with no heterogeneity (\(d=-0.33\); 95% CI = \(-0.54\) to \(-0.13\); \(p<0.001\); \(I^{2}=0\%\); Figure 2E). Neural responses were reported in six studies [52; 53; 54; 55; 56; 57].