The shape of the sagittal curvatures of the spine in a high-level acrobatic gymnasts – comparison by sex

Specific loads on the spine and the very young age at which acrobatic gymnastics training is undertaken require monitoring the shape of the spine curvatures in gymnasts to detect possible postural abnormalities. The aim of this descriptive study was to assess and compare the shape of the spine in the sagittal plane in acrobatic gymnasts of both sexes and their associations with demographic and somatic variables. The study group included 159 acrobatic gymnasts aged 12-19 (106 females and 53 males) from 16 European countries. The study was designed as a survey and measurements of somatic variables and the angles of inclination (using the Baseline Bubble inclinometer) at four topographic points of the spine: S1, L5/S1, Th12/L1, C7/Th1. Based on the angles of spinal inclination, the sizes of the sacral slope (SS), lumbar lordosis (LL), and thoracic kyphosis (TK) were calculated. Body posture was assessed based on Wolański’s modified typology. The angles of SS and LL were significantly higher in females, and TK did not differ between sexes. Training experience positively correlated only with the size of the SS in both sexes. Age and somatic variables were significantly correlated with the size of the sagittal curvatures, mainly in females. The majority of gymnasts had a normal angle of SS and TK and a flattened LL. The equivalent and lordotic types of body posture were more frequent in females, and the kyphotic type in males. The incorrect body posture was noted in 19.8% of females and 43.4% of males. We concluded that acrobatic gymnasts are not at risk of increasing the size of spinal curvatures in the sagittal plane, but males show a tendency toward flattened LL and kyphotic type of body posture.