Simetria da força propulsiva gerada pelas mãos durante o nado borboleta

Abstract

The aim of the study was to analyze the hand force symmetry in butterfly swimming. Fourteen male and female swimmers (18.4 ± 4.9 years old, 71.8 ± 14.6 kg of body mass, 1.78 ± 0.09 m of height and mean performance that corresponds to 74.9 ± 5.8% of the world record). Subjects performed three trials of 25 m of butterfly swimming at maximal speed. Mean and maximum forces were estimated for each hand using pressure sensors of the Aquanex System (Swimming Technology Research, USA). The comparisons between force values for dominant and non-dominant hands were made through Student's T test for dependent samples (p<0.05). In addition, the symmetry Index (SI) was calculated as a relative measure of the force applied by each hand. The mean and maximum force for the dominant hand corresponded, respectively, to 55.7 ± 14.7 N and 114.7 ± 39.6 N. For the non-dominant hand, values were 51.2 ± 14.7 N for mean force and 110.7 ± 36.7 N for maximum force. Significant differences were found between dominant and non-dominant hands for both variables (p<0.01). The symmetry index analysis showed mean values of 8.9% for mean force and of 12.6% for maximum force, and most swimmers presented values higher than 10% for mean and/or maximum forces. Further studies should be performed in order to investigate the relationship between hand force symmetry and swimming performance.Resumo -O objetivo do estudo foi analisar a simetria da força dos membros superiores durante a braçada do nado borboleta. Quatorze nadadores de ambos os sexos (18,4 ± 4,9 anos, massa de 71,8 ± 14,6 kg, estatura de 1,78 ± 0,09 m e com média de desempenho correspondente a 74,9 ± 5,8% do recorde mundial) realizaram três execuções de 25 m máximas nadando borboleta. A força média e a força máxima de cada mão foram estimadas através de sensores de pressão do Sistema Aquanex (Swimming Technology Research, EUA). Comparações entre a força produzida pelos lados dominante e não dominante foram realizadas através do teste t de Student para amostras dependentes (p<0,05). Adicionalmente, foi calculado o índice de simetria como uma medida relativa da força aplicada em cada mão. A força média e a força máxima da mão dominante corresponderam, respectivamente, a 55,7 ± 14,7 N e 114,7 ± 39,6 N. Para a mão não dominante, os valores foram de 51,2 ± 14,7 N para a força média e 110,7 ± 36,7 N para a força máxima. Foram encontradas diferenças significativas entre a mão dominante e não dominante para ambas as variáveis (p<0,01). A análise do índice de simetria mostrou valores médios de 8,9% para a força média e de 12,6% para a força máxima, sendo que a maioria dos nadadores apresentou valores maiores do que 10%, para a força média e/ou máxima. Acredita-se que análises futuras devam ser feitas, buscando relações da assimetria com o desempenho de nado. Palavras-chave: Braços; Lateralidade funcional; Natação.

Interlimb Asymmetries in Swimming and Their Impact on Performance: Evidence From a Scoping Review

“…Twenty-one studies that measured asymmetries during dry-land tests used statistical tests (e.g., t test, Wilcoxon’s, ANOVA, Mann-Whitney, or multiple regression) to analyze the between-limb differences (Table 1). Twelve studies reported no significant side-to-side differences ( p > 0.05) (6,16,17,32,39,45,47,49,50,72,75,85), whereas 9 showed a significant difference ( p < 0.05) in at least one tested variable (21,43,56,59,60,63,67,83,84). The specific metrics that presented significant interlimb differences included the following: triceps electromyographic activity (reported as a % of maximal voluntary load), shoulder medial and lateral rotation (°), subacromial bursa thickness (mm), scapula-humeral rhythm ratio (°), shoulder extension peak of torque (N.m), shoulder external rotation (°), shoulder isolated and composite internal rotation (°), shoulder total arc of motion (°), power output (W), scapula lateral displacement (cm), scapula retraction peak force (N), and scapula protraction:retraction ratio (N).…”

“…Five studies (8.3%) used swimming techniques other than front crawl, and 2 (3.3%) used other swimming techniques additionally to front crawl. Specifically, 3 studies used butterfly stroke (51,59,77), 2 studies used breaststroke (68,77), and 4 studies used backstroke (7,23,36,77).…”

“…Between-limb differences. Eighteen studies used inferential statistics (e.g., t test, Wilcoxon's, ANOVA, or Chi-square) to determine whether side-to-side differences were significant (1,3,5,24,25,27,(33)(34)(35)(36)54,59,(64)(65)(66)73,74,80). They all found significant differences in at least one tested variable (p , 0.05).…”

Muscle Synergy of the Underwater Undulatory Swimming in Elite Male Swimmers

“…Underwater undulatory swimming (UUS), also called dolphin kick or a submerged propulsion technique used in competitive swimming, has gained prominence as a “fifth stroke” (Collard and Oboeuf, 2009 ). There are four well-accepted swimming techniques (butterfly, backstroke, breaststroke, and front crawl), and the UUS is a phase during the start and turn race segments (Pereira et al, 2015 ). In these race events, the present international rules allow swimmers to perform UUS until 15 m after the start and turns for butterfly, front crawl, and backstroke swimming, and only one dolphin kick is allowed for breaststroke.…”

Reliability of using a pressure sensor system to measure in-water force in young competitive swimmers

“…Studies using the differential pressure method reported the measurement of in-water forces using two (e.g., Pereira et al, 2015 ; Bartolomeu et al, 2022 ) or four to eight sensors (e.g., Takagi and Wilson, 1999 ; Koga et al, 2020 ) in swimming strokes. Despite the number of sensors in play, the Aquanex System (a two-hand set-up) showed to be an easy-to-use procedure without encompassing a heavy set-up.…”