# Neuromuscular Excitation Pattern in Expert Indoor Skydivers
## 3 Results
### Neuromuscular Load Indices  
A large posture effect was found in NeLo (F = 37.42; \(\eta_{\rm p}^{2}\) = 0.82; Figure 3a). Indeed, SIT and HD exhibited significantly higher values compared to both PRONE (\(p\) = 0.003, \(g\) = 1.73, and Cl95%= 0.69-2.73 and \(p\) < 0.001, \(g\) = 2.27, and Cl95%= 1.01-3.49 for SIT and HD, respectively; Figure 3a) and SUPINE (\(p\) = 0.003, \(g\) = 1.72, and Cl95%= 0.69-2.71 and \(p\) < 0.001, \(g\) = 4.57, and Cl95%= 2.30-6.84 for SIT and HD, respectively; Figure 3a). No significant difference was found in NeLo between PRONE and SUPINE and between SIT and HD. The two-way ANOVA-RM did not find any interaction between posture and region. For clarity, the muscle groupings used to examine the regional differences in NeloR are as follows: (i) upper-trunk: AD, PD, PM, and LD; (ii) lower-trunk: Rabd and ES; and (iii) lower-limbs: RF and BF. The statistical analysis disclosed a large posture effect on regional muscle excitation (F = 49.13; \(\eta_{\rm p}^{2}\) = 0.86; Figure 3b). Indeed, compared to PRONE, the upper-trunk region showed significantly higher Nelo values during SIT (\(p\) = 0.01, \(g\) = 1.64, and Cl\({}_{95\%}\) = 0.60-2.65; Figure 3b) and HD (\(p\) = 0.01, \(g\) = 1.4, and Cl\({}_{95\%}\) = 0.49-2.28; Figure 3b). Higher values were also found in SIT and HD compared to SUPINE (\(p\) = 0.03, \(g\) = 1.18, and Cl\({}_{95\%}\) = 0.35-1.99 and \(p\) < 0.001, \(g\) = 2.35, and Cl\({}_{95\%}\) = 1.06-3.61 for SIT and HD, respectively; Figure 3b). The lower-trunk region exhibited significantly higher Nelo values during SIT compared to SUPINE (\(p\) < 0.001, \(g\) = 2.34, and Cl\({}_{95\%}\) = 1.06-3.6; Figure 3b) and during HD compared to PRONE (\(p\) = 0.008, \(g\) = 1.45, and Cl\({}_{95\%}\) = 0.52-2.34; Figure 3b); SUPINE (\(p\) < 0.001, \(g\) = 2.56, and Cl\({}_{95\%}\) = 1.19-3.92; Figure 3b); and SIT (\(p\) = 0.013, \(g\) = 1.33, and Cl\({}_{95\%}\) = 0.44-2.18; Figure 3b). Nelo of the lower-limbs region exhibited higher values in only HD compared to PRONE (\(p\) = 0.004, \(g\) = 1.62, and Cl\({}_{95\%}\) = 0.63-2.58; Figure 3b) and SUPINE (\(p\) = 0.004, \(g\) = 1.62, and Cl\({}_{95\%}\) = 0.63-2.59; Figure 3b). SIT appeared to show higher values, albeit not significant (\(p\) = 0.064). No significant differences were found for the regions within the postures. Posture effects were also found by the two-way ANOVA-RM that evaluated the impact of posture and muscle position on the neuromuscular load values grouped according to muscular location (front vs. back side muscles). As mentioned earlier, NeLoFRONT included muscles located on the anterior side (AD, PM, Rabd, and RF), while NeLoBACK values were determined by muscles located on the posterior side (PD, LD, ES, and BF). No interactions were found between posture and position (F = 2.01; \(p\) = 0.140; \(\eta_{\rm p}^{2}\) = 0.20; Figure 3c). A large posture effect was found for muscular electrical activity in both anterior and posterior muscles (F = 37.42; \(p\) < 0.001; \(\eta_{\rm p}^{2}\) = 0.82; Figure 3c). Specifically, NeLoFRONT values doubled during SIT compared to PRONE (\(p\) = 0.003, \(g\) = 1.66, and Cl\({}_{95\%}\) = 0.65-2.64; Figure 3c) and SUPINE (\(p\) = 0.003, \(g\) = 1.69, and Cl\({}_{95\%}\) = 0.67-2.68; Figure 3c). During HD, NeLoFRONT exhibited a more pronounced increase, reaching threefold higher levels compared to both PRONE (\(p\) = 0.011, \(g\) = 1.37, and Cl\({}_{95\%}\) = 0.47-2.24; Figure 3c) and SUPINE values (\(p\) = 0.004, \(g\) = 1.62, and Cl\({}_{95\%}\) = 0.63-2.58; Figure 3c). In regard to NeLoBACK values, SIT differed only from SUPINE values (about +31%MAX, \(p\) = 0.009, \(g\) = 1.43, and Cl\({}_{95\%}\) = 0.51-2.32; Figure 3c), whereas HD exhibited significantly higher values compared to both PRONE (about +54%MAX, \(p\) = 0.008, \(g\) = 1.44, and Cl\({}_{95\%}\) = 0.51-2.33; Figure 3c) and SUPINE (about +58%MAX, \(p\) < 0.001, \(g\) = 3.04, and Cl\({}_{95\%}\) = 1.46-4.60; Figure 3c). No differences were observed in the NeLoBACK values between SIT and HD.