Leonardo Shigaki

Análise comparativa do equilíbrio unipodal de atletas de ginástica rítmica

ABSTRACT Introduction: Rhythmic gymnastics requires a high level of physical quality; therefore, good performance depends on muscular strength and endurance, motor coordination and postural balance. Objective: To develop a comparative analysis of postural balance in rhythmic gymnasts. Methods: 10 female rhythmic gymnasts were evaluated by a force platform on one foot and balance functional tests (Side Hop Test and Figure of Eight Hop Test). The following data of the force platform were analyzed: anteroposterior and mediolateral of the center of pressure parameters, while for the functional tests, the time in seconds was analyzed. Results: Significant difference (p = 0.01) was found between lower limbs in the median frequency parameter in the mediolateral direction, in which non dominant lower limb showed higher postural stability than the dominant one. For functional tests, there was no significant difference between limbs. Conclusion: The difference found in the balance control of mediolateral direction may be related to different muscular actions of the hip region, which is present during the sport practice for stabilization, trunk maintenance, and movement performance with lower limbs. These results indicate the need of a balance program and pelvic sta-bilization for the analyzed athletes in order to maintain muscular symmetry of the limbs for high sports performance.Keywords: postural balance, athletes, sports.

Effects of Holding an External Load on the Standing Balance of Older and Younger Adults With and Without Chronic Low Back Pain

Objective: The purpose of this study was to assess the effect of holding an external load on the standing balance of younger and older adults with and without chronic low back pain (CLBP). Methods: Twenty participants with and 20 without CLBP participated in the study. Each group contained 10 younger (50% men) and 10 older adults (50% men). Participants were instructed to look straight ahead while standing on a force platform during two 120‐second trials with and without holding an external load (10% of body mass). The center of pressure area, mean velocity, and mean frequency in the anteroposterior and mediolateral directions were measured. Results: Older adults had worse standing balance than younger adults did (P < .001, d = 0.20). There were no significant balance differences between participants with and without CLBP within age groups during standing balance condition. However, holding the external load significantly increased postural instability for both age groups and CLBP status, with mean effect size across center of pressure variables of d = 0.82 for older participants without CLBP and d = 2.65 for younger participants without CLBP. These effects for people with CLBP were d = 1.65 for subgroup of older and d = 1.60 for subgroup of younger participants. Conclusion: Holding an external load of 10% of body mass increased postural instability of both younger and older adults with and without CLBP.