The interference of body position with vibration transmission during training on a vibrating platform / A interferência da posição corporal na transmissibilidade vibratória durante o treinamento com plataforma vibratória

Whole-body vibration training on vibrating platforms is widely used for physical exercise, health promotion and physical rehabilitation. The position on the platform is one of the factors responsible for the transmission of vibrations to the body segments of individuals. Therefore, the objective of this study was to compare the characteristics of vibrations transmitted to the body segments of adults between two body positions and different vibration intensities. Twenty intentionally selected subjects (10 men and 10 women), with a mean age of 27.8 ± 2.9 years, participated in the study. The data were acquired with a triaxial accelerometer attached to the subject's body using a vibrating platform at frequencies of 20, 35, 50, and 70 Hz and displacement amplitudes of 2.0 and 6.0 mm in the extended and flexed positions. Descriptive and inferential statistics was applied (p ≤ 0.05). Significant differences in the vibration magnitude and transmissibility were observed between body positions at all intensities analyzed, with greater attenuation of vibrations in the flexed position, especially during passage of the vibratory stimulus through the lower limbs. It was concluded that the body position adopted by the subjects on the vibrating platform directly affects the transmission of vibration. The flexed position was found to be the most suitable for the application of this training method by ensuring better body stability on the platform and promoting more effective attenuation of vibrations, thus preventing the occurrence of unintended acceleration in the head.

O treinamento vibratório de corpo inteiro sobre plataformas vibratórias tem sido muito difundido nos contextos do treinamento físico, promoção da saúde e reabilitação física, sendo o posicionamento sobre a plataforma um dos fatores responsáveis pela transmissão das vibrações às estruturas corporais dos indivíduos. Desta forma, o objetivo geral deste estudo foi comparar as características das vibrações transmitidas às estruturas corporais de adultos em duas posições corporais em diferentes intensidades de vibração. Vinte sujeitos (10 homens e 10 mulheres) com média de idade de 27,8 ± 2,9 anos, foram selecionados de forma intencional. Os dados foram adquiridos com acelerômetros triaxiais fixados ao corpo dos sujeitos sobre uma plataforma vibratória, nas frequências de 20, 35, 50 e 70Hz e amplitudes de deslocamento de 2,0 e 6,0mm, na posição estendida (PE) e posição flexionada (PF). Foi aplicada estatística descritiva e inferencial (p≤0,05). Foram identificadas diferenças estatisticamente significativas na magnitude e transmissibilidade vibratória entre as posições corporais, em todas as intensidades analisadas, com maior atenuação das vibrações na PF, principalmente, durante a passagem dos estímulos vibratórios pelos membros inferiores. Pode-se concluir que a posição corporal adotada pelos sujeitos sobre a plataforma vibratória interfere diretamente na transmissibilidade das vibrações, sendo a PF a mais adequada para aplicação desse método de treinamento, por garantir uma melhor estabilidade corporal sobre a plataforma e promover uma atenuação mais efetiva das vibrações, evitando, assim, a ocorrência de acelerações indesejadas na cabeça.

Reduction mammoplasty improves body posture and decreases the perception of pain.

Women with hypertrophic breasts often experience body pain and posture problems, which tend to be reduced or even eliminated after reduction mammoplasty. The present study aimed to analyze the effects of reduction mammoplasty on anthropometric variables, body posture and pain in women with breast hypertrophy. Eleven women (mean [± SD] age 31.3±10.4 years) participated in the present study. Anthropometric variables, body posture and pain perception were evaluated pretest, and 60 (post60) and 90 (post90) days after reduction mammoplasty. Commercially available posture analysis software was used to analyze the following variables: acromial horizontal alignment (AHA), angle between acromial and anterior superior iliac spines (A-AAIS), vertical alignment of right (R) and left (L) trunk (VAT), vertical alignment of R and L body (VAB) and horizontal alignment of R and L pelvis (HAP). Descriptive statistics and ANOVA for repeated measures were used, and effect sizes (ES) were measured; the level of significance was set at P<0.05. There were no significant differences in anthropometric variables among the assessments. Only HAP-R showed a significant decrease; however, when analyzed, ES, VAT- L and HAP- L in post60, and VAT-R, VAT-L, HAP-R, HAP-L and VAB-L in post90 showed large ES after mammoplasty (ES>0.70). There were significant reductions in pain at post60 and post90 in the neck, cervical spine, back, shoulder and arm (P<0.05). Following mammoplasty, an improvement in body posture, primarily in the alignment of shoulders, trunk and pelvis, and a decrease in pain in the upper limbs and spine, were observed.

Les femmes qui ont une hypertrophie mammaire ont souvent des douleurs et des problèmes de posture, qui ont tendance à diminuer ou même à disparaître après une mammoplastie par réduction mammaire. La présente étude visait à analyser les effets d'une mammoplastie par réduction mammaire sur les variables anthropométriques, la posture et la douleur chez des femmes présentant une hypertrophie mammaire. Onze femmes (âge moyen [± ÉT] de 31,3±10,4 ans) ont participé à la présente étude. Les chercheurs ont évalué les variables anthropométriques, la posture et la perception de la douleur avant l'intervention, puis 60 jours (après 60 jours) et 90 jours (après 90 jours) après la mammoplastie par réduction mammaire. Les chercheurs ont utilisé un logiciel commercial d'analyse de la posture pour évaluer les variables suivantes : alignement horizontal acromial (AHA), angle entre les épines iliaques supérieures acromiales et antérieures (A-ÉIAAS), alignement vertical du tronc (AVT) du côté droit (D) et gauche (G), alignement vertical du corps (AVC) du côté D et G et alignement horizontal du bassin (AHB) du côté D et G. Ils ont utilisé les statistiques descriptives et l'analyse de variance pour les mesures répétées et mesuré l'ampleur de l'effet (AE). Ils ont établi le seuil de signification à P<0,05. Il n'y avait pas de différence significative des variables anthropométriques entre les évaluations. Seul l'AHB-D a révélé une diminution importante, mais à l'analyse, l'AE, l'AVT-G et l'AHB-G après 60 jours, ainsi que l'AVT-D, l'AVT-G, l'AHB-D, l'AHB-G et l'AVC-G après 90 jours ont révélé une importante AE après la mammoplastie (AE>0,70). Les chercheurs ont constaté d'importantes réductions de la douleur dans le cou, la colonne cervicale, le dos, les épaules et les bras après 60 jours et 90 jours (P<0,05). Après la mammoplastie, on observait une amélioration de la posture, surtout dans l'alignement des épaules, du tronc et du bassin, et une diminution de la douleur dans les membres supérieurs et la colonne vertébrale.