# Effect of a Sensorimotor Training Program for Aerial Maneuvers in Junior Surfers
## 4 Discussion
This increase in the previous great SD measuring error might be because not all athletes achieved the same degree of neuromuscular adaptations regarding the implemented training program, which might be explained by the different experience and dry-land training routines among them. However, the fact that both limbs present similar post-program YBT-LQ scores due to a greater increase in YBT-LQ left scores shows that the proposed program, centered on bilateral exercises and/or bilateral motor patterns, induced symmetry between limbs, having a positive effect on movement control and balance in segmental actions, therefore seeming to mitigate pre-program inter-limb asymmetry. The post-program results show that both the right and left anterior reach distance differences (YBT-LQ anterior asymmetry) decreased significantly (\(p\) < 0.05) with a reduction of 56%, which is relevant as an YBT-LQ anterior asymmetry greater than 4 cm is commonly associated with up to a 2.5 times higher risk of lower extremity injury [33]. Many studies also utilize the normalized composite reach distance (composite reach distance (%) = sum of the 3 reach directions/3 times the limb length \(\times\) 100) since its score being below specific cut points is associated with impaired neuromuscular control and an elevated likelihood of lower extremity injuries [31; 33; 34]. However, the composite score could not be applied in this study because cutting points regarding the age, gender, and sport/activity of the individual have yet to be researched in surfing. Nevertheless, the YBT-LQ improved results might also be associated with the verified ankle DF improvements, as it has been previously demonstrated that limited ankle dorsiflexion affects balance control [50], and balance deficits and flexibility asymmetry are linked with a higher risk of lower-limb injuries [51]. Therefore, the improved results of our post-program assessments on these variables may indicate a reduction in these athletes' injury risk level. As to lower limb muscle power, assessed with the CMJa test, another study [36] suggests that top-ranked surfers display a higher vertical jump performance (49.00 \(\pm\) 5.00 cm) when compared to lower-ranked or non-elite surfers (42.00 \(\pm\) 7.00 cm). Our post-program results, despite being lower (37.13 \(\pm\) 7.90 cm), revealed a significant increase of 8.44% (\(p\) < 0.001), which supports the effectiveness of our program in terms of jump height potential development. Our significant but modest results might be explained by the fact that, although this is a sensorimotor program with incremental increases in strength, it is not exclusively a strength training program. In addition, other studies [21; 30] probably included more experienced junior surfers in terms of their training physical performance when compared to our athletes, who potentially needed a higher frequency of training, either more time/an extended training program, and/or a more focused lower limbs strengthening program to achieve the same physical level. In fact, lower body strength and power seem to be determinants in competitive surfing and overall performance [37, 52, 53], as stronger surfing athletes seem to be able to develop significantly greater eccentric peak velocity [36], to brake more effectively, and to better use the landing/eccentric phase, optimizing their jumping performance [44]. This load absorption optimization while landing an aerial is also related to increased ankle dorsiflexion [14], which confirms the importance of the assessment of the three variables analyzed (ankle DF, YBT-LQ, and CMJa), also supported by our results. A previous study of junior surfing athletes' physical performance level [15, 51] also revealed some degree of un-structured training strategies (e.g., type, frequency, intensity of training), which might not fully address the physical needs of the surfers, considering the tasks to be performed.