Kinematic analysis of the spine and hip for the “Danilova” artistic gymnastics element

Abstract

Introduction Women’s artistic gymnastics is a sport that has experienced a continuous evolution over the years, both from a technical point of view and from the point of view of the correctness of the executions. Flexibility, strength, dexterity, and many other motor qualities are present in this sport. Danilova or “free (aerial) walkover forward” is an acrobatic flight element in artistic gymnastics. This element can be executed both on the floor and on the balance beam, but most frequently on the beam, being an element of difficulty D (0.4 points). Material and methods 13 artistic gymnasts, components of junior and senior Romanian Olympic teams (age: 14 ± 1.93 years, height: 149.35 ± 7.94 cm, weight: 40.01 ± 7.41 kg) were recruited for the study. The gymnasts performed the free (aerial) walkover forward (Danilova) element on the floor. To record the element for obtaining the three-dimensional kinematic data analysis, gymnasts have been equipped with a multiple sensor suit. Data collection consisted of gathering data simultaneously from all 17 sensors. In order to get accurate data regarding the range of motion in joint angles, motion trackers were positioned on segments, in special locations. Results Our data show that during the final phase of the execution of the free (aerial) walkover forward element, all gymnasts presented the extension of the spinal column, at two different moments: i) when the foot comes in contact with the ground, in the landing phase and ii) when lifting the torso in the final stage of the landing phase, respectively. Our results revealed that the second extension is significantly greater than the first one in all gymnasts (maximal spinal extension (M.S.E.): -46.76 ± 2.521) vs. spinal extension at foot contact (S.E.F.C.)-39.32 ± 2.309, p<0.05). The data analysis showed that there is no correlation between the S.E.F.C and the length of the Danilova element. The hip joint angle was in moderate positive correlation with the M.S.E. (Pearson r= 0.5808, R2= 0.3374), but not with the S.E.F.C. (Pearson r= -0.304, R2= 0.09243). The completion of the element is the result of either mobility of the spine or compensation due to hip extension. The length of the Danilova element was not found to be correlated with neither of the parameters (hip extension S.E.F.C, M.S.E.). A lower degree of mobility of the lumbar area is not an impediment in performing an accurate Danilova element, some gymnasts being able to perform a significantly shorter element (the found length range of the Danilova element within the study group is 0.94-1.43 m). Conclusion A good performance of free (aerial) walkover forward is possible either in the case of increased mobility at the level of the lumbar spine or, with the help of compensation in the mobility of the hip joint. The secondary spinal extension is presented as a cofactor with an assistance role during the stage of returning to the initial position.