| Description |
Exercise on the beam is particularly stressful for the lower limbs, as the take-offs and landings are performed on a relatively hard surface. The aim of this work was to create a weekly load summation on the beam of 9 artistic gymnasts of junior and senior age participating in the highest national competition. Furthermore, the objective was to perform a pilot measurement of the dynamic values of take-off and landing in 6 selected elements on the beam. Reaction forces were measured using the Bertec platform, where the gymnast, a member of the national team of the Czech Republic, performed three attempts of elements: Switch leap, Johnson, Handspring fwd with flight to land on one leg, Flic-flac with step-out, Aerial cartwheel – landing in cross, Salto swd tucked take off from one leg to side stand. From video records of training, we evaluated that each gymnast performed 211 ± 59 jumps and leaps, and acrobatic elements on average per week. We found out that the gymnast performed 125 double leg take-offs (59%), 63 take-offs (30%) from the right foot and 23 (11%) from the left foot on average. Regarding landings, 47 (22%) were performed on both legs, 121 (57%) on the right foot and 43 (21%) on the left foot (all gymnasts preferred the right lower limb as a takeoff leg in the handspring forward). The vertical forces of take-offs and landings were as follows: Switch leap (2.8 and 3.5 BW), Johnson (3.0 and 3.6 BW), Handspring forward (1.1 and 3.0 BW), Flic-flac with step-out (1, 7 and 1.8 BW), Aerial cartwheel (2.7 and 3.2 BW) and Salto swd tucked take off from one leg to side stand (2.8 and 2.7 BW). The forces in the anterio-posterior axis proved to be the highest for Johnson (0.8 and 0.9 BW). The forces measured in the mediolateral axis reached values of up to 0.6 BW. The results showed that, in most cases, takeoff forces were lower than landing force, or these phases were force-balanced. This pilot study leads us to the conclusion that the number of elements loading lower limbs asymmetrically on the beam is not negligible. Especially in terms of landings, that are more demanding according to our dynamic measurements, gymnasts load only one leg in 71%. We recommend gymnasts to perform compensatory exercises that would help prevent the musculoskeletal imbalances. It is also necessary to follow up on this pilot study and carry out further extensive and more detailed research in this field.
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